Activated The Great Smokey Mountain National Forest

Here is the after action report where I finally activated a park in North Carolina. The Great Smokey Mountain National Park is a well used park in the POTA network, but it was one that I had not yet activated in my travels.

This particular area is called the Cataloochee valley and there is a heard of elk in this area that I like to try to photograph in the fall. Well since I was here, had a radio and the elk were not very close either…why not POTA?!? I decided to activate this park the night before and gave myself a decent little window of time to get it done in as well since I wasn’t sure how the elk would be doing… I had remembered from the last time that cell service was nonexistent here so I scheduled the activation on the POTA site the night before just as a precaution. This is a pro tip, if you even think you are not gonna have internet, go ahead and schedule the activation and pay close attention to the time as it is UTC time on the website and don’t do like I did and get the time off by several hours because you chose the wrong time zone… I did this on another activation and the results are as you think.

I found this spot and setup the truck-tenna (a hamstick on a receiver hitch mount I made) and the Ten Tec Argonaut 5 for this activation to just get on the air as I wasn’t sure how long I would have with band conditions being not great lately, so I wanted to stack the odds in my favor as much as possible ahead of time. Well it worked… as you will see later.

Here is a sign that lets you know just how unpredictable wild animals can be… Elk are VERY large creatures so it is prudent to heed this warning… I also thought it was interesting that the park rangers have to put out these signs at all… I guess getting a selfie is more important than getting killed by a bull elk…who knows?

This is what i found on this day though. The whole heard was just chillin in the edge of the treeline, so it wasn’t too heart stopping of an event to photograph them on this day. It was fun to just sit and peer at them through the camera for a while though. I have a video on my YouTube channel that showed a few more photos as well as talks about the rest of the trip some more as well.

Back to the activation though… I ran the coax into the cab as it was kind of cool this morning so I wanted to stay warm while I operated and just ran the cable through the window and left it down a little while I did since it wasn’t raining. This 15’ coax is just long enough to reach in this configuration too, which is nice.

Here we have the operating position today. I just sat the Argonaut in the seat, added a common mode chock and hooked up the HamGadgets cw keyer and my N3ZN tiny paddle and I got on the air. Power for the radio is pulled straight off of the truck batteries if I operate from this location as I have a power cable ran to the cab from the battery with power poles on it just for this. The arm rest makes for a decent desk, but it could be better. At some point I plan to make a table top that sits on the arm rest and goes forward to the shifter and even has a leg that sits on the console to support it as well. This will probably be covered with some sort of cloth so it wont be so rough on the arms and will allow me to spread out the notebook, pen and key a little more.

I could tell that the scheduled activation on the POTA site was working as I almost immediately got a pile up once I went live on the air and the RBN picked me up. It is night and day different as to what you get with and without the reverse beacon network picking you up. One QSO of note here is the Canadian call on the first page. We had quite the QSO and spent a few minutes chatting about things before I got back to the activation and went to work on that. I am not one to shy away from a ragchew even though I wanted to work a bunch of contacts too, it is all about talking on the radio so I love all of it.

I had a steady stream of calls come in for a little over an hour. that is awesome! I love it when I am able to catch what I think is all the QSOs that are calling. The band was really strong today too as I was only using 15 watts and was able to get really good signal reports back from most everyone. It was a really stable day as well as it can also be seen in the log that the signal reports were steady and not sinusoidal. Sixty three contacts later I called QRT to go get some lunch and fuel for the truck before heading on to Ashville for the afternoon. If you are interested in the rest of the trip, I have a YouTube channel where I talk about the photography aspect more. Thanks for coming along and until next time, go get on the air!

72

WK4DS

Something special finally happened to me at a POTA park...

Today had been a pretty busy one at work, so afterwards I wanted to go over to K-2169 (Cloudland Canyon State Park) and just work some contacts to take my mind off things and to just relax for a while since it was 77 degrees on November 7th!

I get my sBitx V2 and head over there with the plan to run my hamsticks since I only have about 2 hours, maybe less, to get my activation in before dark. I roll up to the frisbee golf parking lot and notice another car in the lot with an antenna on the roof…a very large antenna mind you when compared to the ones you usually see on top of smaller cars.

I go ahead and park in my usual location and decide to walk over to see if there is someone in the car and THERE WAS! What do you know, I found another ham already doing POTA! It was none other than KB4QXI (John Law) and he was working SSB with a 20 meter hamstick on the roof of his car none the less. It only took me a year and a half and over 120 activations at this one park to finally run into another ham radio operator doing POTA. John had a pretty sweet system setup in his car with a computer, I assume for logging as I failed to ask him if that is what it was for, but I am pretty sure it is. He was also running a Yaesu radio of some sort on a mount that placed it right in hand’s reach but out of the way of the passenger seat, which happened to be where the computer was residing. I failed to get a photo of any of that so just let your minds run amuck with the verbal description and we will move on.

After talking with John for a while we agreed that it would be best if I setup in the next parking area down the hill which is right at 2/10s of a mile away. I personally figured that was far enough that we shouldn’t have problems with cross talk if I went to 30 meters since I was going to be operating with CW anyway since he was already on 20 meters when I arrived. I figured that if 30 meters was really bad that I could just drop down to 40 instead and work all the locals. Lol. Something else I had not noticed was that this lot had powerlines running right over it (as you can see in the above photo). I figured at this point I might as well give it a shot anyway and see if I could get the activation at the minimum. I did only have about 2 hours till the end of the UTC day at this point.

I setup three counter poise wires, you can see one of them in the photo I took above just barely because I forgot to get a closer photo prior to it getting dark… soooo. Suffice it to say, I ran out the two 30 meter tuned radials and even had the opportunity to run them elevated about 5 or 6 feet above grade, which is probably why my radio worked so well on 30 tonight to the point I didn’t move off that band. Tuned radials seem to work SO much better than radials that are just close. The key when I operate from the truck seat can vary between the Gemini and the N3ZN paddle, it just depends on the mood I am in as well as how fast I want to setup as the Gemini is in the carry tote and the paddle is in the hard case with the Argonaut 5… I normally choose my paddle based solely on things like this as I really like using them all.

After talking to some of the more code savvy hams in the email reflector on the bitx group and them helping me solve the code problem (actually they solved it and told me how to implement it), I was able to get the FT8 mode operational. It actually worked when you called CQ already and it had an issue operating when you would answer someone else calling CQ. It is a stop gap fix that does allow it to work but it doesnt work as efficiently as it should. Still it got FT8 working for me so I am stoked!

To be fair, this is Ashhar’s first iteration of this mode in his hand coded software he wrote and it does work so I got no complaints as it allows me to work the mode WITHOUT the need of an additional computer. He is currently testing a revision that works even better so I am excited to see what happens with that. In the photo above you can see the exchanges and the log entry for my QSO with K4SQL. This is all in the radio too!

On the way out, it was pitch black as it now gets dark at 5:30…uggg. Have I mentioned how much I dislike Daylight “Savings” Time? Well, I dont like it… This is a prime reason too. Even without DST being implemented, it would be dark at 8PM in November. Regardless, I had to use a flash light to break down my antenna tonight.

I powered down and quit before the UTC day flipped over as that would have forced me to stay two more hours to get a second activation in…lol. I do need one more activation at this park to get me over 4000 QSOs. I never planned on getting that many QSOs at one park to be honest, my only goal to start off with was to get 20 activations so I could get the repeat offender award, now I am well north of 120 activations and almost 4000 QSOs! By the time this blog post goes live, I should be past that mark.

Something else of note is that I am currently still logging my FT8 QSOs on my paper log and typing them into HAMRS as there isnt that many of them at this point and I can easily keep up with this quantity manually instead of learning how to export them from the radio and then add them to my HAMRS log electronically or even a new logging program of some sort instead. There will be a point when I will have to do that, but for now I can still get them in the log like this really easily. So till next time warm up the air waves with your radio and hopefully I will work you from a park!

73

WK4DS

2 x POTA Activations plus a new to me mode! FT8 has entered the chat!

I have been busy lately so I thought I would combine the AARs for two activations into one report. These went very fast, well, one of them did. the other did last a coupe of hours and involved me doing something very new for me…FT8…just not with the Penntek TR35. It was used to make CW contacts at the first activation.

The first park I went to was my hometown park K-2169 Cloudland Canyon State Park. This is my go to park when I don’t have a lot of time. I also can go to the Sittons Gulch parking area which is much closer than the top of the mountain by a solid 15 minutes of driving. Well, this is where I went and during the week, I can also get to choose my parking space most of the time too. Today proved a little tough but it worked out. When I got to the park there were a few cars already there and they were literally in all the places I like to setup, save one… So luckily for me there was a space in a corner like I prefer to use as it gives me room to deploy my counterpoise wires and not have to worry about people tripping over them.

I also only deployed a single counterpoise element today as well. I was curious if it would heavily affect my ability to make contacts with only a single radial, but it didn’t seem to matter much on this day. Due to my spot, I was able to run it straight away from the truck too for what that is worth. Seems that if I don’t use a radial at all, the hamstick will use the coax and the truck body for the counter poise and I will have about a 1.8:1 SWR on the nanoVNA, but if I simply add once tuned radial, it drops to 1.2:1 and if I add two it is pretty much 1:1 SWR. This is why I always deploy at least one if there is time at all, it helps with my transmission pretty dramatically. I found this chart online and used it as a reference to see what would be the results of better antenna SWR and as you can see, at 1.8:1 you lose almost 10% of your energy and at 1.2:1 you only lose about 1%. This is why I don’t worry about deploying both radials if I am in a time crunch. I also know that there are a lot of other things at play here like radiation pattern and take off angle, but it is pretty consistent since it is a ham stick every time and I cant easily change that.

Once setup I immediately jump on 20 meters to get things going today and it did not disappoint! 20 meters was alive and well on this day with a lot of activity.

Today’s weapon of choice is the Penntek TR35 Amateur Transceiver. I bought this radio last year for this reason alone and it took me a while to get around to using it as I was trying to get my IC-705 up and running at the time. I finally came around to the concept that the 705 just wasn’t for me and stopped using it. Sometimes a radio, even a wonderful machine like the 705, just isn’t the radio you want to use, so I sold it back in August. I kept this radio though as I really love the whole radio, literally the whole thing is as close to a perfect CW rig as I could get. It has every function you need on the surface that you could want and nothing you don’t need. The built in filters are really well done and it can even listen to SSB if you are into that sort of thing. The compact size also makes for another reason I like this machine, it is destined to be my new travel radio replacing the venerable Elecraft K1 that I also sold last August due to lack of use. I do want to add an antenna tuner at some point to this kit so I can use random wire antennas, but for now it has a tuned antenna in the kit.

This is the kit when setup. The Penntek TR35, the N6ARA Tinykey, a set of simple headphones (with an adapter to make it play out of both ears) and a 10 cell AA battery pack. I chose a 10 cell pack as it will give me almost 13 volts when the batteries are charged and I can use alkaline cells in a pinch by bypassing two cells with a couple of dummy cells I made in the machine shop. The kit also includes several pens, a pencil (since they don’t dry out), a Field Notes notebook, a couple of lengths of coax, one of which has a ferrite bead common mode choke built into it, a 40M EFHW antenna with an additional radial for it and a throwline with a weight, everything you could need to get the little machine on the air.

Here is another thing I like about using my truck for POTA, I can use the bedcover for a table and just spread everything out on top of it like you see in this picture. If I can operate outside I will always choose that option, but sometimes, the weather or time just prohibit that.

I had a good run with the little Penntek TR35 as you can see in the log. So if you wonder how well things can go, this is a 5 watt radio into a hamstick on my truck. It is one of the worst possible arrangements you can possibly come up with and I still ended up with almost two pages of contacts. Now if the bands are trash, then all bets are off, but you really don’t need a ton of power to do a POTA activation and have a good time. On to…

North Chickamauga Creek WMA K-3958

The next outing was in Tennessee at the North Chickamauga Creek WMA in Soddy Daisy TN. This little park has not seen a ton of activations and to prove that, just go to this parks page on the site and look at who (with only two activations mind you) in the top activator and also who holds the highest QSO count as of this writing. Yeah, it is me. There have been some people activate this park, but it just doesn’t get the attendance of places like The Great Smokey Mountains or even Cloudland Canyon State Park. I don’t understand why either, it has easy access and is pretty close to town. Maybe after I write about it and give it some notoriety it will see some more attendance…who knows?

I was here on a Friday during the mid day hours, so the park was pretty much abandoned except for me and a couple with their dog in the river bottom. I setup in a spot where I had room to deploy a radial and got the sBitx v2 out this time as it has a mode built in that the Penntek TR35 does not…well actually it has a bunch of modes that the Penntek doesn’t have, but this radio is special in that it will do FT8 natively in the radio. Yeah, no computer, no sound card, no setting up complicated software, no figuring out how to get the computer to talk to the radio and vice versa. You just choose FT8 from the mode list, dial up the frequency, set a few things like your call sign and grid locator and hit Call CQ. Now, the radio is a beta version of sorts and it has a few bugs to work out, one of them is currently in the FT8 section too, as long as I am calling CQ and a QSO ensues, the whole thing works like clockwork, but if I answer another operator’s CQ it has a glitch and wont sequence correctly. So I can use it for now, but only if I call CQ. Even so, it still works and I made almost a dozen contacts on this day with FT8, so I am happy about being able to use another mode on activations.

Here you can see a QSO has just finished with WD5BFH and the radio even logged it for me! Oh yeah, it even has a logging program running in the background to log your QSOs as well. I really like this radio.

Here we have the antenna layout for today, the single radial was really close to 45 degrees due to the slope behind the truck. That made the SWR even better and I was stoked to get on the air and see what I could find out there in radioland.

I am also testing the reserve capacity of this 8aH battery I bought last year off of Amazon, I keep turning the power up higher and higher to see if the battery can handle it and today saw me using 30 watts of power for almost two hours! I shut down the activation because of time constraints and not because of the battery so it works great for my needs.

Once again I was able to setup on the truck bed cover, and I am acutely aware that I need an easier logging process. Hand written logs are nice, but they are slow to transcribe. I am thinking that I too can come into the 21st century and use a computer to do my logging…I know, I know. I have really railed on battery powered devices, but at some point I guess I just need to bite the bullet and get a computer of some sort for logging. I am thinking of using a Linux based OS for this as these seem to be more reliable and do not update and crash all your stuff… windows, I am looking at you.

This display below is not how it looks when booted up for the sBitx V2 in the native configuration. I have scrolled it down to be able to see the top QSO in the logbook so I can confirm the QSO did in fact get logged when running FT8. The photo underneath this one is what the screen looks like when opened initially. The screen has more information than can be displayed normally so since it is a web browser layout, you simple scroll down to see the other intel. Things like the on-screen keyboard, the logbook and the macros (message memories) are what you find when you scrll down. But the way I have it here is an efficient way to run this mode for me as you can see everything you need on one screen. Sorry for the reflections, it was tough getting this frame outdoors.

This is the native layout at startup.

You can see the time stamps for the FT8 contacts are pretty spread out. This is a function of my operating skill level being low and the lack of “responding to other calls” being buggy with this mode. I know this because the band was on fire that day.

All in all I had a great couple of outings for POTA and radio in general. I hope you enjoyed these after action reports and look forward to seeing you again soon!

73

WK4DS

sBitx V2 Amateur Transceiver Mods for POTA Use

My newest radio, the HF Signals sBitx v2, is an HF radio with so many features that you just need to follow this link over to their website to see what it is capable of. Once you have finished going down that rabbit hole, come back over here to see what mods I have done to mine already for my POTA stuff. I want to say this right away, this radio is kind of in Beta, so if you don’t like to open up the radio and tinker with it in both the software as well as the hardware, this probably isn’t the radio for you. With that out of the way, let’s get started!

I decided to get in on this idea of a open source architecture radio design. I found this company, HFSignals, and they make several radios with their latest model being the sBitx V2. This is a touch screen radio with a huge screen and it is powered by a Raspberry Pi SBC. Using a legit computer to power the radio unlocks so many things that this radio can do that other radios can not do. For one, it will do FT8 IN THE RADIO! Yeah, no external computer needed at all, that in itself is a gamechanger and don’t be surprised if you see the big names in the industry doing this in the near future because of it. By using a Raspberry Pi SBC for the brains, this little machine is just chocked full of goodies that those other radios cant do.

FT8 is native inside the radio on the sBitx v2.

You heard that right, as I type this blog post it is on the bench next to me finishing a QSO with I1RJP, and when it does it will automatically put the QSO in my log for me. How awesome is that? Did I mention it is open source? Yeah, both the software AND the hardware are open source and it is encouraged to take your radio apart and tinker with it. Shoot, it even shipped to me with a spare set of output transistors in the accessory bag. These are well thought out but they are still rather simple overall designs with features like they are passively cooled radios and use a crystal filter network. Another thing about being passively cooled is that it means there is no fan noise to deal with at all this way, since there are no fans.

Well… I used it on a POTA activation and the little radio got HOT. Really hot to be honest. So I decided that since this radio is designed from the outset to be open source and to be tinkered with by the end user and I wanted to use it for POTA activations, that I would add some fans to cool the little machine on activations.

The first thing I wanted to tackle was the power amplifier heat sink. It is a great heat sink and does a wonderful job as it became really hot during the activation. I first started looking for a suitable fan in my junk box and found the perfect fan in an old computer power supply that I have cut apart for another project. The fan was still mounted in the sheet metal case which also happened to fit perfectly over the outer edges of the heatsink. All I needed to do was trim the sides down so it sat next to the heatsink and add some screw holes to attach it with.

Once I had it mounted with a couple of self threading screws, it was time to get it running. I went inside the radio and started looking for a suitable place to tap power out to it and found the incoming source point was the best, but the fan would run all the time if I used this spot…

Enter a simple electronic circuit that could be used for any temperature of fan control and could even be adjustable with a potentiometer if you were so inclined. This circuit is a simple power transistor rated for 6 amps of max draw (I used this so it could handle the 300mA of draw from the fan and not need a heat sink and they are still really cheap too). You simple have a voltage divider network for the base of the transistor where you have a fixed resistance between the base and ground and you add a thermistor (a temperature reactive resistor) between the voltage source and the base.

I chose a 10K ohm negative coefficient thermistor for my needs as this design has the resistance go down as the temperature goes up. The fan is simply wired in series with the transistor’s collector and the voltage source and the transistor is basically used as a electronic relay in the simplest form. I know the MOSFETS are more efficient, but this works and I had all of these parts (except the thermistor) on hand so I used these instead.

What happens during operation is that when powered up, the thermistor has so much resistance at a lower temperature that the base voltage is less than the .7 VDC required to bias the transistor since the fixed resistance of the base to emitter side of the voltage divider is calculated for the desired temperature. The thermistors have a chart showing the resistance at different temperatures so you can make these calculations fairly easily. Mine worked out to 270 ohms for the fixed resistance between the base and emitter. So you can imagine that with 10,000 ohms (at 77 degrees) on the other half of the voltage divider you only get .363 VDC on the base of the transistor and the transistor stays “OFF”…

I found the above chart online for 10k ohm thermistors and grabbed it for reference only. This may not be the right chart for your thermistor as they have different resistance curves so check with your brand of device and make sure you have the right chart for your device. Back to the story in progress…

Well knowing this, as per the chart above when the temp rises to about 107 degrees then the resistance drops in the thermistor to about 4980 ohms and this now allows about .7 VDC to develop across the base of the transistor, forward biasing it. Notice how I made the contact with the hear sink. I soldered on a pair of wires and put heat shrink tubing on them to insulate the connections then I ran a 1/4-28 tap down into the space between two fins cutting something resembling threads into the fins. Then I took a piece of a zip tie and put it on the thermistor and ran a setscrew down against the ziptie/thermistor stack to hold the thermistor against the heat sink it works really well too. The ziptie is only there to do two things, to prevent me from cracking the outer shell of the thermistor and to insulate the thermistor from the setscrew so the setscrew wont bleed off heat, I am not certain it helps, but it sounded good in my head at the time. LOL. I located it near the transistors so it will pick up the heat faster. I also changed the mica thermal spacers out for aluminum ceramic instead as those are supposed to conduct heat significantly better between the power transistors and the heatsink.

The fan control circuit can be seen on the perf board next to it in this photo.

Then once things heat up the fan spools up and blows on the heat sink, in turn cooling it down to the point where the temperature on the thermistor drops enough to raise the resistance back up and shut off the transistor again. This worked like a charm at the last activation I used the sBitx v2 on. The fan doesn’t even come on to drain the battery until the heat sink warms up enough to need it, so if your simply listening around or hunting activators and doing search and pounce, then the fan will not cycle on very often at all… if ever. I do understand that there is some current flowing through the resistor network all the time though as well, but it is low and I am not really worried about 3mAs of current anyway. I have really large batteries in the grand scheme of things and if I am going to hike with a radio it will be the Penntek TR-35 anyway…

The next “upgrade” I did to mine was to add a heat sink and fan module to my Raspberry Pi 4 SBC (single board computer) that is the heart of the sBitx radio. The original configuration has the SBC mounted right on the RF board with very little space between the two for airflow and no room at all for a fan of any kind as you can see above in the photo with the side radio cover removed. I did some experiments with positioning fans above the heat vent opening above the Pi and could feel that the air I was pulling out was quite warm. This led me to the assumption that the SBC would run smoother (and probably last longer) if it had a proper heat sink installed on it. You see as my unit would run, with time, it would start to lag a little from information input, like adjusting the VFO would result in the numbers jumping on the display instead of a smooth change as the knob is turned. I noticed when the fan was pulling air across it that this would be reduced significantly if not eliminated. So the mission became “how do I get a fan on this thing to cool it properly”

So I start looking at adding an external fan but ultimately that didn’t look really feasible as I wanted to pull the heat off of the Pi properly and not with just slight air movement. A case fan would only help a little and I am pretty sure at this point that the SBC needs a little more help than that. Enter a riser kit from amazon and a heat sink assembly with fans from one of those Raspberry Pi bundles that comes with the pi, a small case and a heat sink with fans. I measure every thing and come up with a height to elevate the SBC and check the cabinet and sure enough, there is plenty of room to add it. So I get it all together and when you get the riser kit from amazon, you get the little screw-in standoffs as well as the header socket extender to extend the pins up to the Pi once installed. If you will look closely in the photo below, you can see one of the fans and the heat sink fins for the SBC heat sink that I added to the Raspberry Pi SBC to help cool it.

In the above photo you can see the pin extender i also had to add so the Pi would plug in once elevated for the heat sink module. This worked wonderfully for fitment and I was stoked to have the heat sink on the SBC finally, but I still had to connect the fans to power to get them to run. Instead of putting them on a heat sensor, like the power amp fan, I chose to wire these straight to the main power switch on the sBitx so that when you turn it on, they spool up and run the whole time. My reasoning is that the computer will be working the whole time as the radio is in constant “refresh” mode so to speak as the sBitx software package has to keep everything up to date in real time on the display, then there is the background applications that are also running like the telnet server and dx cluster stuff and the other applications should they be active. Logically the SBC will be running nonstop, so lets just run the fans all the time…

This is where I run into a problem…

Did you notice where I drew power to run the fans? That seems completely reasonable for someone who just successfully wired up a fan on a temperature sensing circuit for the power amplifier. Well, it turns out that the fans for a Raspberry Pi are not 13.8VDC fans but rather 5VDC fans as they are designed to be plugged into the SBC IO header bus and not driven from a 13.8 VDC source. Let me tell you something, when you run a 5 volt fan on nearly 14 volts it sounds like a jet engine preparing for take off! On top of that, I had a pair of them!

I had brought the radio to the house and connected it to power to play with it and hunt some POTA activators and the whole time I am thinking to myself… “Man, these tiny little 25mm fans sure are loud…” but after about 10 minutes (yes, they lasted that long and in fact lasted much longer) I started to smell hot plastic… I shut down the radio and took it apart to find the fans incredibly hot and seriously, “soft” to the touch.

Back to the workshop and I figured out what I had done. So I start working on a way to lower the voltage that would not cause RF hash inside the radio cabinet. Those little buck converters from amazon are notorious for causing RF hash so that was out. This simplest thing to do was to put a big resistor in series with the fans. I had put them on a 5 VDC supply in the shop and measured the current draw so it was a simple matter to do a little ohms law and come up with about 50 ohms of resistance to mitigate the excess voltage from the supply. Also these fans pull very little current and I am running them at 4 VDC instead of the full 5 volts as they are rated to run from 3.3 to 5 VDC. This way they will be a little quieter too or at least that is my thinking and it gives me a little leeway should the voltage go down lower or even a little higher.

Inside this heatshrink is (4) 200 ohm 5 watt resistors soldered in parallel so make a 50 ohm 20 watt resistor.

Well the brute force approach worked and the (4) 200 ohm, 5 watt resistors in parallel dropped the voltage down to a very workable level. The resistors dissipate about 1/2 of a watt of heat total so I put them out of the way from everything else and it works, it just works. Maybe later I will add some sort of active voltage regulator and do it so that I don’t have to just burn off the excess power nonstop to keep the fans at the right speed. Maybe something like a 555 timer biasing a mosfet for pulse width modulation to keep the power draw down and keep fan speed at a constant level. I don’t know, I will look at that later, for now, the brute force resistor idea is working just fine.

Once I got the fans turned back on, I found “I had a rod knocking” in one of the fans… figures that if you run them at almost 3 times the rated voltage that something like a bearing fails in the fan… well I just ordered another set from amazon and swapped them a couple of days later and now we are all set. So it would seem at least as when I went to reassemble the radio I found that my USB and Ethernet ports no longer lined up with the openings in the side plate for the radio.

Turns out that if you have a fully equipped machine shop, this isn’t a real problem though. It could have been solved with a good file and probably a half hour of work, but who wants to do that if you have a CNC milling machine at your disposal? So I put it in the milling machine and manually open up the exiting holes to allow use of the ports and by default I also created air vents for the Pi to get fresh air to it much easier now. This also seems to work really well for the time being. Better air flow, adding a heat sink and FANS!!! The Pi runs cool now.

I also did a couple capacitor mods that I found on YouTube as well. A fellow on the interwebs had done these same capacitor mods and they made sense to me so I went ahead and added them as well. The following video describing these mods and why.

To summarize his video, he added decoupling capacitors to the three jacks on the side of the radio to drain off stray RF. He also adds one across the incoming supply lines to kill transients and possible RF on the power. Please note that in the photo below I have the plus side marked on the capacitor, this is incorrect as the board is marked erroneously and I translated that error to my cap as you can see in the photo. Check the supply on your radio with a meter before installing caps that can not be reverse biased. We all know how that would end…

One last thing I also did was to add some heatsinks (also per the video above) to the power devices inside the radio to help them survive use during digital modes. They worked just fine when I ran them with CW but when operating digital, the duty cycle is a lot higher so I didn’t want to risk thermal failure because of something as simple as adding a heat sink. This also comes from the above video and just made sense to me too, so I added them. The radio operates great and I really like using it for FT8 when calling CQ (more on this later) as well as for CW. I have some other mods planned for the future so another blog post describing these mods will be in order at some point. Till then, thanks for your time and attention and I hope this helps someone out there with their radio.

WK4DS

72

A quickie activation at Cloudland Canyon

Today I only had a short time and I wanted to get on the air so I loaded up the sBitx v2 and headed on over after work.

So I get to the Sitton’s Gulch parking area at the bottom of the mountain so I can save another 15 minutes of diriving time. I am in luck too as the parking lot was really empty to a and it allowed me to choose my favorite spot.

To get things on the air faster, I also used my hamstick for 20 meters and just ran out one counterpoise radial. Another thing that I realized today is that I need to work on my antenna parts as the radial was broken and the sta-kon also broke off where I connect it to the antenna mount… there is always something to do it seems. Luckily I made the mount to where I could also insert just the end of the wire and it would still work. This arrangment provided me with a 1.2:1 SWR as shown on the sBitx radio when I would transmit.

I also found that the wire was also broken in the middle as well. So I simply twisted it back together and just used it. It seemed to work just fine, well…it got the job done... I know there was something probably amiss with the current flow, but it got me on the air. We all know it works better when you have a continuous piece of wire, but if you don’t have one, you use what you have. In hindsight I should have just gotten the other radial out for it as I have two just alike, but you forget simple things like that when you are stressed out with a short timetable to work with.

Another noteworthy thing that happened today was that I rolled down the back window for the first time is about 3 or 4 years. You see this window stopped working several years ago and I knew what was wrong. The wiring passage from the truck to the door where the wire bends will eventually break these wires, it is an absolute that it will happen. Shortly later the other back door also failed in the same exact way (It is still broken as of this writing). Well, I finally got off my lazy rear end and ripped the truck apart last weekend and actually rebuilt the wiring harness through the flex conduit as you can see in the photos below. I plan to do the other door soon and I will actually video that process and plan to put it on my YouTube channel. It allows me to roll the window up and down AND the power door locks works in this door again!!! WOOHOO!!! You just don’t understand how convenient having this feature is until you don’t have it. Every single conductor was broken too, literally not a single wire was intact…lol.

Testing the connections before routing the wires back through the door and into the chassis post.

That was then and this is now, and now it his high flex silicone wire in the high stress area of the conduit so it should last the rest of the life of the truck at this point. Now to do the other door this coming Saturday morning if all goes according to plan.

The radio of choice today was the sBitx V2 that I ordered back in August. I have had this radio for a little while now and I really like it, it does have a few quirks I would like to iron out, but for the most part the little radio works really well for me. I have done a couple of mods to it that I felt needed to be done pretty soon as it would get crazy hot on a POTA activation. (There is a blog post where I used it a time or two in this blog if your interested that I wrote about before this post.) The main one was that I added a fan to the power amplifier heat sink that is temperature controlled so it cycles on when the heat sink gets to about 115 degrees. I will spell that out in a blog post incase you want to add something like this to your radio. You can put the fan control circuit on any radio and not just the sBitx. I thought it was a brilliant idea to monitor the temp and the fan works so well that it will cycle on for about 1 minute or maybe two and then cycle back off as it has cooled it down low enough to drop out my monitor circuit.

Another huge benefit to using a radio that is basically a computer with an RF deck attached is that you can do things with it that you can only dream of on other radios. The photo above is a perfect example of what I am talking about. This is the bank of TWELVE message memories that I use when operating POTA as an activator or a hunter. To be honest though, F3 thru F8 don’t get used at all, I thought it would work for me but my process flow while activating just doesn’t allow for it at this time so I still send this part of the exchange manually. But the CQ sections and sometimes the others do see a good bit of use. I use the CLOSE memory to give me time to log the contact in my logbook during pile ups. When the pile up comes, I don’t have time to send some of the exchanges and also write so I use this to be able to write down the information for the exchange at times. If things are slow enough, I will usually just send everything though as I like to send CW, it is just nice to have things like this to help.

Another thing you don’t see in the photo that is available, is that you are not limited to 12 memories, but you can open the little box beside F12 and choose another bank of 12 from another menu item, here is the cool part, you can have as many pages of 12 memories as you want, the only limit is your memory on the Pi. It is literally a script you fill out and save in a folder on the Raspberry Pi. That is just plain awesome. Another thing that is nice is that mine has the Real Time Clock module and if you will notice it knows what the time is so I don’t have to try to use my phone to tell the time for the contact info. If I were to work on it a little harder, I could even do my logging on the radio as it has logging software built in and can be configured to work with the mode you are using. I just like to log on a paper notebook myself and have not bothered to learn it. That is what the section right about the macros is for…

All in all it was a great outing albeit very short. I did have to get back home pretty quick so after I cleared the small but rather exciting pileup, I called CQ a few times and when I got no answers I called QRT with 20 QSOs in the log. Two of those QSOs were DX too! One was Canada and the other was Spain of all places! The Spanish station was booming in as well, very loud to my hamstick. I don’t know if he sent back a 599 because I was also just as loud or if he thought I was simply sending a contest style exchange, but it was nice to work him none the less and I did it with 25 watts too, for a 30 minute activation, that ain’t bad in my book.

All in all it was a great time to get out and make some contacts and to use the sBitx out in the field too. (Which is what I bought it for to start with.) So more to come from this wonderful little radio and my park adventures! Until next time, 73 and get your radio out!

WK4DS

K-6307 Herky Huffman/ Bull Creek WMA Activation AAR

This was a spontaneous activation of sorts… we went from Melbourne FL to basically Tampa today and on the way I had about an hour to get in a quick POTA activation. So I get on the app and start looking for parks along the way.

So I decided to go to K-6307 Herky Huffman WMA and I chose this one on purpose as it is literally across the street from another POTA park K-6330 Triple N Ranch WMA and on the map there is a road into Triple N Ranch less than 1/4 mile from the parking area at K-6307 so it isnt a 2fer but they are close enough that I could feasibly activate both in a short time. Just pick up the gear enough to drive down the road to the other entrance and park there to do the other park. Seemed simple enough, well it wasnt as it turns out.

The calendar was in that box you see in the above photo. It was nice to know if there was a hunt going on or not. You know to avoid bullets and such. Lol.

So off we go and immediately leave the hustle and bustle of Melbourne and it turns into farmland surrounded by wilderness all at once...or so it seems. A stark contrast to the coast for sure just a few miles away. It was kinda neat seeing the stark contrast like that actually. It just showed us how close nature really is sometimes if you want to go see it.

This is where I chose to setup today at K-6307. It is a parking area for the Herky Huffman/Bull Creek WMA and the truck is so far back next to the fence because that was in the shade. It was in the mid 80s and in the sun that gets hot pretty quick. When I did an about face from the same spot, you see the next image(below). I am standing on the shoulder of the road. This is a different POTA park…so close yet so far away.

As you can see on the above image, the road literally divides the two parks and is in neither of them so there is no way to get a 2fer here. BUT if I can gain access to both then I should be able to get a little 2 park rove instead, at least that is the idea.

Well, I drove down the road a little to the gate for Triple N Ranch and it was locked. Figures, you win some, you lose some. With that I decided to simply operate at the other park as long as possible instead. This netted almost 40 QSOs into the log which is awesome! The hamstick really is a great portable antenna for ops such as this where time is kinda short and deployment would be tough for a wire antenna as the underbrush here is really sharp…

Once I had a spot picked I had to move the truck back and fourth a little to get the antenna in a spot where it didnt touch any tree branches so I could radiate as good as possible. Especially since it is near the tip of the antenna and that is where the voltage is the highest. Also in the essence of saving time, I once again only put out one radial as this speeds up deployment a good bit and seems to net almost as good results.

Also of note is that we were in transit between two towns here as well so Teresa decided to simply take a nap in the truck while I operated from the bed cover. That is a luxury of CW that voice modes do not enjoy, quiet operation in low noise areas.

Below you can just see the radial running away from the truck and wait till you see the QSO map of how well it works!

Here is the operating position for this activation, the bed cover. If you will notice, you don’t see the battery. This is because I am powering the rig from a power cord I made up and put in the cab for winter ops. It is wired straight to the batteries with a fuse and powerpoles. It is just long enough to reach the bed cover if I set the radio in this location. Pretty smooth if you ask me. Lol. I like to spread the stuff out if I have room so I don’t bump a knob or something. The only knob I typically use once I setup on a frequency is the multifunction knob for RIT control occasionally. I adjust CW speed these days on the picokeyer so that is lifted from the radio too. Super simple operating procedure to be honest.

This is what it looks like to have decent band conditions, a 15 watt transmitter, and a 20 meter hamstick with a tuned counterpoise radial attached to it. This is a good day in my book. This happened in just under an hour too so not too shabby if you ask me. I had a good time so that is all that matters to me. LOL.

Once my time had ran out, I called QRT and we headed on down the road to our next location for the night. All in all it was a great day for POTA even thought I couldn’t net two parks in one day. It just means I need to return to the other park now to activate it…that is a great excuse to go to Florida! Until next time, I will look for you on the bands!

72

de WK4DS - David

Activating K-2169 and some notes about radials and SWR that I saw today...

Ok. Radials

Today saw the use of the sBitx v2 again as I wanted to work some FT8 as well as CW. I setup at the frisbee golf parking lot on top of the hill and decide to measure the SWR plot as well as check to see the Smith plot as well of the ham stick antenna and add counter poise wires till it quit making it better. I did this because I received a comment from a ham asking about any info I might have onthis subject since he is wanting to pick up a ham stick and mess around with it.

In the above photo, we have the ham stick on the receiver hitch mount that elevates the radiator to about 6’ to the bottom of the antenna. The antenna is only wired to the cab of the truck with a 15’ piece of coax and it terminates into the nanoVNA through a common mode choke. At this point I had not turned on the 2nd trace to see the smith chart…sorry about that. In all fairness, this could be used on the air with practically no worries, I would probably turn the power down to prevent heating of the finals from the SWR, but that is me being cautious. This is completely usable to be honest.

In the above image I have added a single, approximately 15’, radial and ran it straight out away from the back of the truck. This is completely usable and I have had great activations with just this one counter poise wire. Dropping from 1.574:1 down to 1.226:1 doesn’t sound like much but it really is when you are working towards a resonant antenna. Also notice how the null point is climbing in frequency as the radial field grows under the antenna.

In this photo we see the SWR plot has gotten spectacular! I added the tuned radials for the 17m antenna to the one radial I already had installed so now I am using three radials with the antenna and look at that plot. I arranged them 90 degrees apart as this also matters. The more this angle changes the more the SWR changes too. Sometimes for the better, sometimes for the worse. Notice how it raised the frequency of resonance as I added counter poise wires to the system and it lowered the SWR to 1.028:1 as well as made the antenna slightly inductive instead of capacitive. This shows that the radials are more than simply a ground path but rather part of the tuned circuit that matches the radios transmit frequency and improved that whole system. If you have the space and time, I highly recommend adding counterpoise wires to your system and measuring it with something like a nanoVNA.

Another thing I learned is that I get best performance when the wires are pulled snug as you see in the photo above. I think this might have something to do with when I originally set it all up, I tuned them with them under tension like this which makes the wires the longest and also this changes the capacitance and inductance of the radial from just being thrown on the ground. As a matter of fact, it was when I tensioned the radial shown above that the SWR plot bottomed out like you see. It was the last one to be tightened and it made a huge difference.

By parking in this location I am able to get the radial at almost a 45 degree angle to the antenna or very near it. This matters as it is the point in the radiation pattern where to get a 50 ohm impedance match to the coax feeding it. There is tons of information out there on how to adjust the impedance of the antenna by adjust the angle of the radials…it is like some sort of dark magic to be honest.

I got on the air and started on 15 meters as it looked promising today with the noise floor being good and FT8 being quite active. As you can see though it took me quite some time to get just 6 QSOs in the log. After I worked N7ZLD I went over 20 minutes without a single call, that was when I decided to jump on FT8 to see if I could get a few in the log like that. It was slow going, but that it the fault of the radio software more than band conditions so I was happy to get 4 FT8 QSOs in the log, securing the activation only on 15 meters for a change!

After playing on 15 meters for a while I decided to see what 20 meters sounded like (I didn’t even check the antenna, I just plugged it in and got on with the activation). I quickly found myself in a small pileup working through several call and the calls kept coming in for a good while one after the other and sometimes two at once. This is the pace I really like as I don’t feel like I am missing anyone that wants the park I am at. After a great run on 20 meters CW I once again switched over to FT8 to see if I could get a few there. It took me a while to get someone on the hook, but I did work 5 more and the last one was W0NKA!!! That is (W -zero- NKA) and he is awesome, go look him up on QRZ and see about the special event he is having in December where you can get the golden ticket!

All in all it was a wonderful activation and I hope you enjoyed following along today, until next time I hope to hear you on the air.

72

WK4DS

Activating K-1832 Anastasia SP in Florida!

Today I got to activate another new-to-me park! Anastasia State Park (K-1832) located in St Augustine, Florida.

Today was a special day for two reasons. The first reason is I am in St Augustine Florida and the second is that I had about an hour to fit in a POTA activation. So I drop off the wife at the yoga studio and from this parking lot I have about 1 hour and ten minutes to goto a park, setup a radio, get 10 contacts, tear it all back down, grab some photos for the blog post and go back to the yoga studio. I can report that I was successful in the mission.

So I chose Anastasia State Park because of its proximity to the yoga studio. It was a 7 minute drive to the spot where I setup the radio from the yoga studio parking lot…there goes 14 minutes of my 70! Part of the game so we are off!

There is a park access fee to use Anastasia State Park. It is 4$… Not bad for such a lovely place complete with a snack shop and even a restaurant from what I could tell. Not to mention THE BEACH! Did I mention it has BEACH ACCESS?!?!? Well, it is some of the most beautiful beach I have seen in the mainland USA to be quite honest about it.

The scene above was down the street from where I setup for the activation. This is the life! As you can see the salt water (The Atlantic Ocean) was also in close proximity so propagation should be good! It also had good “facilities” at this location too as I had just finished drinking a bunch of coffee… lol This is not a perk I am used to having at most locations. There is a restroom at the canyons edge back home at Cloudland Canyon next to the parking lot but my usual spot at the frisbee golf course has no such luxury so I was glad to see it today. Sometimes its the little things that make all the difference…

The location I chose was next to the shop where you rent small watercraft like kayaks and such. Since it was a Monday morning there were practically no people there. In the photo above you can see the sand dunes at the beach in the background. This is a good spot for POTA. Salt water has a reputation for being one of the best ground planes in radio and I normally dont have access to salt water so I get really excited when I can operate near salt water.

The parking area is on the side of the road (notice the wind swept trees, isnt that cool?) and backs up to a fence so I backed in and set up the 20 meter hamstick on the truck. Since time was of the essence here, I opted for a single radial and ran it over the fence and out into the recreational space on the other side. I threw the nanoVNA on it right quick and the SWR was good at 1.3:1 so on the air I went! I opted to hop straight way on 20 meters as this band usually has the highest percentage of operators of all the bands. This proved to be a wise decision too as I secured the activation in short order thanks to the plentiful hunters that sought me out today.

I get setup in the truck and power on the radio to a very active band, also giving me hope! So I start calling and it doesn’t take long to get a reply. Then the gates open! Wow! There were so many hunters! I actually got a little overwhelmed and couldn’t send code for squat!!! (Apologies to all of you guys and gals where I butchered your call sign trying to send decent code) So I just took a deep breath and started with the loudest stations and cleared the pileup in a little while. Since I was in Florida and not at home I could hear stations that are normally deaf to my radio and antenna combination. I logged several Tennessee contacts today and even one or two from the west coast!

I might modify this operating position just a little more with time, but it is almost perfect now. I would like to make a small stand that sits in front of the armrest that will hold the N3ZN key and PICO keyer allowing me to move the logbook a little more forward. Currently the bottom of the page is hard to reach for my old back as it is almost behind me. Lol. But other than that, this staion setup is going to end up being my wintertime POTA activation setup for the upcoming winter.

Looking at the QSO map shows that the skip distance today for my hamstick lies in the 500 to 1200 mile range and the second hop is coming down on the west coast. The signal reports on these stations (west coast) today were rough. I struggled to copy the call sign on one for certain and probably both. Still got them into the logbook though so we are good. But it did reveal to me how much energy is lost in that second “hop”. It was significantly weaker copy on those stations. I am going to speculate that it was probably 6 full S units of signal weaker. I dont use the S meter as a strict reference but today I found myself comparing signals such as these weak ones running in the S2-3 range and the Tennessee stations booking in at S9!

When I am back at my home the west is still difficult but at those times I normally have both counterpoise wires setup and this seems to alter the takeoff angle a little and I will get Utah, Colorado and Arizona and even the Dakotas sometimes so the other counterpoise seems to make a big difference in lowering the take off angle some to improve propagation to those areas for me. I am also fortunate to be where there is an abundance of ham radio operators so I can easily secure my activation due to the sheer density of hams most of the time. Actually I have only failed to secure the activation one time and that was my fault entirely, not because of a lack of hunters, but me not calling where they were hunting… Anyway, that is another story and is in the blog somewhere if you would like to read that sometime.

Looking back over the log and seeing all those Tennessee contacts makes me happy to know that I was able to activate a park in Florida even if it was only for an hour, it was still a great time and I was able to get a bunch of people into the log that day that is always a good reason to activate! Till next time…

73

WK4DS - David

Activated a new-to-me park today! K-3958

Today was a good day for POTA. I activated North Chickamauga Creek Wildlife Management Area and it was fun! You see, for me to get 80 QSOs in one outing recorded into the log is a feat of the airwaves, so that made this trip one for the books!

K-3958 is also just outside of Soddy Daisy Tennessee at the foot of Mobray mountain. I was concerned when I chose this park that I would have trouble securing the activation as this parking area is right at the base of the previously mentioned mountain. I decided to give it a shot anyway though since I have had great activations at Cloudland in a similar scenario. This WMA is also situated is a gorge and goes right up to the side of the road, the problem is unlike K-0716 on the north end of Lookout mtn where there is a pulloff, this park doesn’t have one on the road. This means my only shot at activating this park today was to find a spot inside the actual parking area itself.

So I roll into the parking lot and start looking for a space that would be suitable for setting up a station out of the truck. I quickly realized that since it was Saturday and near town that it was a popular “waterpark” for the local youth. The lot was almost COMPLETELY full with only a few spaces that were not suitable for most cars. Since I drive a huge 4x4 truck though, this problem posed little challenge for me. I soon found the spot you see in the photos and got started building a radio station. I had just enough room to fit into this space too as you see here, the truck just did clear the trees.

Well, this was kinda tough as to get out of the road, I had to back right up to the bushes. So here I am, bushwhacking my way around the back of the truck as I get out the mount, antennas and run a coax to the cab of the truck. I ran the station from the front seat today in an effort to keep dust under control as the road is literally 7 feet away and is gravel. Compound this with people driving pretty fast as well and it was fairly dusty at times. This was the main reason for giving up on the outside station idea today.

Once setup, I start considering my plan, I figured that I would start on 20 meters so I could be sure to get enough QSOs to secure the activation as the spot page showed a disproportionate amount of activity on this band. Well, let me tell you that my fears about not being able to make contact from this location were completely unfounded. This location could hear just fine. I setup on 20 meters and start calling CQ and it didnt take long at all to get a run of contacts in the log that secured the activation! After that they just kept going and going and going!

Parking is kinda tough here, you have to get the right spot for POTA and on a nice Saturday, this lot is FULL, I recommend coming through the week so there is more room.

This is what the parking lot looked like. Just cars pulled out of the way of moving traffic on the side of the road for the most part. Some spaces were built into the tree line like where I parked and then a ton were like this photo above. Almost all of them had cars in them too. The ones in the trees that were open also normally has something that made a car being there a bad idea, like mine had this huge rock in it but I had enough ground clearance to fit anyway so it all worked out

Today’s weapon of choice was the Ten Tec Argonaut 5 feeding into my hamstick collection. This is one of my all time favorite radios even though it is larger than my other rigs. It is capable of 20 watts but I never run it that hard with 15 watts being my personal maximum output power. Today saw it running at that 15 watt level because I was thinking I needed it to get over Mobray mountain since I was setup literally right at the foot of it. Across the road from where I was setup it starts going uphill and goes straight up the side of the mountain. In my opinion, this is probably the worst possible location to setup a radio, but it worked today so I am not going to complain…

I have found that the hard shell case for the radio makes a great table to sit it on. I like to use the radio in the passenger seat when I run solo ops (which is most of the time). I like this operating position as it allows me to sit comfortably in the truck and operate. This keeps me out of the sun, and I can activate in the rain from this position as well. The Dodge arm rest in the 2005 year model is a huge flat surface too so it turns into a nice little table. Since it is vinyl upholstered, the key doesn’t move around at all on it either, making this the almost perfect work surface for my POTA fun time shenanigans! If you will notice, the window behind the radio was only slightly down. This is because I was trying to minimize the dust buildup in the truck from people flying by right in front of me, there seemed to be no shortage of fast drivers in this tight area for some reason…

Well I sat on 20 meters for about an hour and made contacts the WHOLE TIME! Wow! The hunters were out in force today!!! I made FOURTY NINE QSOs in just over an hour!!! That is awesome! I looked at the POTA page for this park and that one thing alone put me on the top five activator QSO board. It is going to be a great day for the WK4DS POTA operation…

So at this point the QSO rate had dropped off and I figured I would try 17 meters to see what I could do there. Well, there was RF in the shack on this band and this little PICO Keyer is not RF friendly…at all, if there is RF near it, it will start sending strange characters and it would do this on 17 meters today, this told me the SWR was probably a little high due to the position of the counterpoise and so I folded on 17 and went instead to 30 meters.

The nice thing about 30 meters is that it allows you to operate into areas that is only reachable by BOTH 20 and 40 meters. It is strange in that it acts like both bands for some reason. I can make long distance contacts and then the next one will be in Georgia… You just never know with 30 meters how it will work. Well today it worked REALLY well, with me making 28 QSOs on this band in about the same number of minutes. The bands were on fire today! Wow! It did get me quite a few local states as well with North Carolina, Tennessee, Georgia, Alabama and Mississippi coming into the log at this point.

The photos above show what everybody was coming to see. The river is beautiful but the water was way down with only a small stream actually running right now and that made for several pools that the people would congregate around to swim in. I found a couple of fishermen at this spot and they said they were not having any luck due to the low water levels. I grabbed a couple of quick photos and headed back to the truck…

After having such good runs on 20 and 30 meters I figured I would drop down to 40 meters and see what was going on there. Forty meters was not happy today, well at this point in the day that is. Seems that the atmosphere was not happy with my attempt at this band and only allowed me 3 QSOs before I called it quits and went QRT with 80 QSOs in the log for one day. I wrapped up the radio and antenna system and then headed home with a new park and a ton of contacts, what else do you need for a great day of radio? I will go back to this park again but next time I want to go on a week day and see what I can do with less people in the park. But until then, I hope to hear you on the air. 73 WK4DS

Finally got my sBitx V2 radio…so I went to a park!!!

Quick synopsis is I like it. Read on to see why.

When you see this radio, you think it is like one of the big name machines. It is not. It is actually so much more because of the nature of the project that it comes from.

The HF Signals sBitx V2 is an evolution in their radio designs and brings so much to the table that is cant be described in one blog post…well maybe…I can write as much as I want in one post…lol.

The TR-35’s magic is the lack of menus.

The first thing you notice it the lack of buttons or switches like my Penntek TR-35 has on it in the photo above. There are simply two knobs and a display and that is all you are greeted with at first glance.

Well this is a kind of sleight of hand trick as the display is actually a touch screen and almost all of the controls are driven from this display. In fact, what appears to be at AF Gain (volume) knob, is actually like the multi-function knob on my Ten Tec Omni 7 being selectable for an array of things it can control.

Both knobs are also push buttons and the smaller one defaults to volume control if pressed, but the larger (VFO) knob doesnt appear to do anything when pressed, I can not find anything in the literature describing it so it is there for tinkerers from what I gather. You see, this is an open source SDR, this menas you can download the source code and if you are savvy with coding, you can add features or modify how the radio works to suit you. This is the point of the whole project to be quite honest. This radio does work, but it is not as polished as a big brand machine as it is intended for the owner to go inside and play with things, like add circuits or modify existing ones or even write new features to add to the radio outright. You can literally download the schematic and the actual source code from their GitHub… What ever you want to do, this radio is fully “unlocked” so that you can do it.

Enough about the radio in general, how did it do on the first outing to a POTA park? Well, it did really well, I did power it from the truck battery which means I had to setup in the truck somewhere so the power cable would reach the connection I have in the truck. (I finally added a power pole cable inside the truck cable that is fed directly from the batteries so losses are a minimum.

Back to what I was saying, I got to K-2169 and setup in the truck so I have somewhere to sit this time as I planned to stay a while today and didn’t want to have to stand up the whole time. It took me a few minutes to get it all organized, but once I did, everything fit quite well. I wanted to use my N3ZN key, but to be honest, this arrangement literally made it impossible, so I defaulted to the little travel key I have used so much over the last year. I didn’t have a table top that was convenient to setup the other key on and I even tried to sit the N3ZN key on my clipboard, but it was just too difficult and I kept running into problems trying to use it. Hence you see the Gemini cw paddle in my hand for this activation.

Once I settled on the key and radio, I chose 15 meters to get on the air, the band was wide open and even the propagation report said it would do well… Well, FT8 was rocking pretty strong (I tend to use these guys for my beacon report on a band), so I move down into the CW area and start calling CQ…and I call and I call…and nothing. Seems either no one was on the band or they simply could not hear me. It did appear that the band was fading in and out pretty bad though as the RBN would give me a great report one minute and then it would go 3 minutes without a single update. So after what seemed like an eternity on 15 meters, calling CQ with no answers I caved and went down to 17 meters to see what I can scare up.

The hamstick collection at this point. 15 (Green), 17 (Brown), 20 (Yellow), 30 (Blue) & 40 meters (Red) are all represented here (well, 30 meters was on the truck when I took this photo)

So since I had not edited the memories in the sBitx V2 yet for my use, I planned to use the PICO Keyer I picked up a while back, well it worked somewhat, I think it had trouble keying the radio because the radio is looking for contact closure and not a semiconductor so it would work, but it was introducing errors into the code pretty bad. I finally threw in the towel and just used the key the whole time and ran with it. This turned out to work really well though and I really didn’t mind it after all. Once I got home I built a complete set of memories for the keyer complete with all sorts of messages. You get as many memories as you want, they are in sets of twelve, I tested this by copying the CW1 memory and renaming it then I edited the messages and saved it, rebooted the radio (just as a precaution) and the new set of messages were right there in the drop down menu! They are really simple to edit, but you need a keyboard to do it. I didn’t take one with me on this trip hence I didn’t bother with trying till I got back home. If there is demand for it, I will detail how I added a memory and show how to edit the messages and the message names as well.

So I ended up using almost 4 Amp Hours of energy on this activation. Not bad for over 50 contacts in the log. I am happy with that! When I am going to be at the park for a while, I will get all the antennas out and sort them by band like you see below. Well, they are not sorted at this point, but imagine that they are for the story. Then I can change bands quickly and easily as I will lay them near the mount for the truck. The 2” PVC pipe is maxed out too. I don’t think I can get another antenna in it at this point. If you plan to run hamsticks, I recommend that you get some sort of tube to store them in to protect them. They are not very durable in construction so it would be best to try to store them in a way that will make them last.

You see, I know the radio is transmitting as I have been using it at home for the past week or so before taking it to the field. So I get down to 17 meters, find a clear frequency and start calling CQ here. Well things pick up for me here as I get a few answers so I know the radio is in fact working as it should and I didnt do something to it while I had it taken apart… More on that later when I talk about the mods I did to this radio right out of the box.

So after messing around on 17 for a few minutes I hit a dead spot, so I figure it is a good time to QSY down to 20 meters and see what I can find down there. Well, I found all the ham radio ops in the United States and some from across the Atlantic too! I proceed to make over FOURTY contacts in an almost continuous stream in about as many minutes! I was busy! The radio was working great too. At this point, I clear all the callers and decide to try the lower bands for a minute and see what I can do there.

So I hop on 40 meters first as this antenna has consistently been on the upper edge of SWR for my operating preferences, and the sBitx agreed with it showing about 2.1:1 while I was there. Also of note is that the radio self adjusts the output power based on band and SWR from what I can tell. I was running about 20 or so watts on 20 meters and wihtout changing the power setting at all, jumping on 40 meters netted me 9 watts output into the 2.1:1 SWR where on 20 meters I think the SWR was closer to 1.2:1… So I turned up the drive some in an attempt to get the power out consistent across the whole activation. I didnt get it past 15 watts if I remember right… But it was enough to make a few contacts and get some in the log from more local hams as the 20 meter band hops right over the closer states.

Then I finally moved up to 30 meters to see what it could do as well since that was the only antenna I had not tried yet. Well, 30 meters also did not let me down…like 15 meters did… haha. I got it on the band with good SWR and output power and easily made several QSOs on that band to finish up the HF portion of this activation.

The next part is just for fun, but I also recently got a new HT (Handy Talky) radio and was playing with it while out on this day. So I called into the KG4WBI/R 1.25m repeater to see if Roger was monitoring and he was. So then I asked him to switch his radio to VFO and simplex so we could make a 1.25m FM UHF contact. 5 watts was more than enough to make the trip the roughly 3 or so miles it was to his house from my location! So I netted 54 contacts on this day on 5 bands and two modes. I had a great activation and the sBitx pulled quite a long shift on it’s first outing.

Now to discuss some issues I found with the new radio that I am going to look into solving or upgrading. The first one is actually really easy, it needs a fan… or two. The heat sink got SO hot in the two hours I was in the field operating at about 20 to 25 watts. REALLY hot, the whole radio was hot actually and I think this is what made it start doing the next issue..

This is something I noticed after a while, when the radio is getting really warm, it starts to “stutter” in the refresh rate of the screen. I am thinking this is due to thermal throttling of the Raspberry Pi processor in an attempt to prevent sudden death from overheating. I confirmed this was not due to ram overflow by swapping the Pi out with a second one I own that has 8GB of onboard ram and it did it too with minimal use “on the air” back in the shack at home. So my solution is two fold, one is to install a fan on the main heatsink for the power amplifier in the RF deck and a second fan pulling air through the radio chassis where the Pi is located in an attempt to cool the processor as well. I know this will increase current draw from the battery, but I am not concerned with this as my activations normally don’t run over two hours at a time and this limits amp hour usage to usually no more than 3 or 4 amp hours, which even my smaller battery can handle at this time. If adding the fans runs the draw up to 5 amp hours or even 10 in an activation, then I will just take a bigger battery since this is not a backpacking radio in my book. Also, it did work at 25 watts down to 15 watts, depending on band and SWR, for the whole activation. If I were to just turn the power down to 5 watts, it probably wouldn’t get warm enough to matter on the power amplifier considering the size of the heat sink on it. This means I will probably install a small toggle switch to manually cut the power to the fans should I want to run it at true QRP levels in the field. I also plan to wire the fans through a circuit that will automatically turn them on and off as needed to prevent them from just drinking the battery dry when they are not needed. This involves a small temperature sensitive resistor called a thermistor in a voltage divider and a transistor to flow current to the fan. This way if the radio doesn’t get very hot, it wont come on at all. I think I did the math on this device and it will bias the transistor base at about 105F degrees, which is about right for it to protect the electronics. The processor cooling fan could be done the same way (and probably will) but I don’t want this fan to be very large so I am searching for a small 12 VDC fan for this application and also I want to see if I have room to install the processor heatsink, which is not currently installed. This alone will help tremendously, but with long activations the heat will eventually soak the heatsink and we will be right back to square one. This is why I want to add forced air flow to the system…

Even with all the heat buildup, the radio trucked right along and I put over 50 contacts in the log on the first outing! I even got some from overseas in the log!!! It is always good to get some DX in the logbook. I really liked this radio for a station that will be near the truck. The reason for this is that it is fairly large and heavy compared to my other radios, well maybe the Argonaut 5 is similar in weight. This is one of the reasons the Argonaut 5 doesn’t go on activations that stray far from the vehicle too. That guy is heavy, and it is a fairly fragile radio like the sBitx V2. So who knows what I will end up using it for, but for now, it will be one of my POTA radios.

All that aside, the radio works really well for the most part and over time this will be a wonderful little rig to run on activaitons. I plan to get it going on digital modes as well so I can work contacts on FT8, PSK31 and RTTY as well since it does all those modes natively and without the need for an external computer. This was one of the main reasons for getting this radio, I really didn’t want to have to bring an additional computer to the field to do digital modes… Anyway, with all that said, I packed up and on the way out found a few deer wandering around the area and I was able to get a photo of one of them. That was just icing on the cake for a day with so much activity and fun and getting to use my new radio. So until next week, get your radio out and go make a contact with it!

POTA Activation AAR and some antenna testing.

Let’s take a look at hamstick antennas and see how they perform without tuning the counterpoise for each band.

No POTA outing is complete without some good ole McDonalds java to get you cranked up. I normally make my coffee at home but today I was in a bit of a hurry so I went through the drive through and picked up some of their magic water. Today I chose the Sittons Gulch parking lot at the bottom of the mountain as it is significantly closer to my home compared to the upper lot. Google Maps says it is a full 15 minute drive from one lot to the other. So operating from here gives me an additional 1/2 hour on the air. That is awesome.

So I setup the station in the truck today and learn a few things that I didn’t know before. One is that the power port on the dash I use is not great at carrying the load of a 20 watt radio. I can see the voltage dip to almost 11 volts on transmit. This is not good. So I opted to switch to the battery and get the voltage back to where it needs to be. This means that I now have another side project to fix this socket… But I am also going to install a direct power feed to the cab of the truck for my winter time ops so I can power the radio off of the truck batteries directly and install a anderson powerpole outlet inside the truck.

Today saw the battery deliver another 2 amp hours of supply, that is four total so far for the 8 amp hour cell. If I get 6 out of it at this point, I will be happy. It is over a year old at this point and it is still going strong. This is not some big name brand battery either but rather some cell I found on Amazon last year. It has seen many activations too. I used it heavily when I was using the Icom IC-705 and kept it in the backpack with the radio. Then when I transitioned to my Penntek TR-35 I used it with that radio for months. So this battery has seen a significant amount of use. I am impressed.

Another thing I have been doing is testing the antennas on the same set of radials (the set I tuned for 40/20 meters) and just switching out the vertical radiator only. I was pleasantly surprised at what I found out today to be quite honest.

Ham-stick antennas work shockingly well for what they are. So well in fact that I am about to go on a 10 park rover operation and use only the 20 meter ham stick (unless the band closes then I will move… lol) for the whole event. My strategy being that 20 meters is the most popular band by far so I should be able to get ten contacts at each park pretty easily. This should give me the best odds at completing my rove and making it to ten in one day. Below is the report from my nanoVNA showing each band I have a ham-stick for and just using the same counterpoise every time. (Side note here, I was also deploying the counterpoise differently too so as to keep them out of the way and this also affects the antenna, see the photo below there is a photo further down in the post showing them). The plots are arranged from the highest band to the lowest but after seeing the results, I don’t think it matters as I dont see a pattern to be honest.

15 meters kinda threw me for a loop. I need to trim the “stinger” some and push this one up into the band more. The null is actually at something like 20.250mhz so yeah, this one needs work. I didn’t have my cutters with me or I would have done it right then. Even so, the SWR was still low enough to get on the air and I was getting RBN reports as high as 20dB which is phenomenal for a 15 watt signal out of a ham-stick several hundred miles away…that is off-tune.

17 meters also caught me off guard. Look at that plot with radials tuned for 20 meters instead! Ft8 on this band will be epic! I have plans to start doing some digital modes during POTA outings in the future so I am happy to see this.

20 meters actually needs trimming too. I have known this for a while, but it is close enough for CW so I have not bothered yet. As you can see, at 14.060mhz on this day, with this radial arrangement, it was still less than 1.2:1SWR. I have had this particular radiator the longest out of my entire collection and bought it last year in anticipation of winter ops. Which it worked perfectly for me in that role. This is why I have slowly collected the set I have now. They just work.

30 meters is honestly the best looking lower band out of the three that I have. 20 is tuned low and 40 needs some help with more radials (most likely), but 30 meters lands just right, with the null point covering the whole band.

40 meters is odd to me. It works and has respectable SWR even with a poor radial field but I would like to see it even better if possible. I think this is more to do with the antenna design and poor counterpoise than anything else. The other bands work great but this one is just not that awesome and I am still sorting it out. Dont get me wrong, 1.46:1 SWR is great but I think it can be alot better. I just need to dial in the counterpoise or something. I am also going to setup another trace on smith chart to see if I am capacitive or inductive and not purely resistive. That might be part of the problem. The SWR plot is nice for simple and quick checks but there is more data to consider. More to come on this…

I did all my tests with the common mode choke installed so I would know what the radio actually is transmitting into. This way I dont get surprises along the way from things not being like they were when I did my test.

The logbook today looked good too. I didn’t have a long time to work the activation so I was happy to see 23 get into the log today. That is a good day for me. I was a little sad though since I was getting picked up on the RBN and could hear stations on 15 meters but no one could hear me… Oh well, maybe next time.

I messed up the sequence and had to correct it. Hence all the scribble in the margin… sorry about that.

Thanks for coming along on this after action report, hope to work you on the air soon!

72

WK4DS

A POTA activation that was incredibly rewarding!!!

When we activate a park we never know what is going to happen.

So today is Labor day here in the USA. This is the first Monday in September set aside for the workers of this country to grill out with their buddies and such as that. So for me that means going out and setting up a POTA activation somewhere. I decided on Cloudland Canyon after deciding that the drive time to other parks would make the activation very short for me and I wanted more time on the air instead. I choose the upper parking lot since I wanted to use my hamstick system instead of rigging to the trees today. The trees I normally use have a lot of traffic today from hikers and I didn’t want them tripping over antenna wires all day so this just made sense. As you can see below, there was plenty of room for me here today…

I don’t know if I have shared this or not, but I have converted all of my hamsticks to this QD system so band changes are fast. It works really well, I do need to retune my antennas though as this did lengthen them a little and now they are all low on the meter for their center frequency… always something to do…lol.

Once installed, these mounts work really well and the tune is very stable, I have not seen it change at all from the numbers on the VNA since adding these QD adapters. So if you think you might want to use hamsticks for POTA, I really like them. Now to be honest, I don’t think I would use them for mobile (in motion on the roadway) use as there is a lot of leverage on this little mount and the spring is not that heavy to me, they might work fine like that and probably have been deployed that way, but for me, this is a site setup tool only.

Another reason for the hamstick setup is the use of the truck for shade during the activation. By strategic positioning of the truck I can leave the doors open with the engine off and not have RFI from the operating parts of the truck to contend with as well as having a natural shade from the sun too. I use this trick a lot when I don’t have a ton of time for an activation and want to operate in inclement weather like rain. Simple and robust, plus the system just works, look at the logbook below and tell me how hamsticks don’t work…

I carry all of the stuff in the photo below in the hard-shell case that I keep the Ten Tec Argonaut 5 in so I don’t have to search for cables or things like my key. It is all in there and I just grab the case and go. This makes life so much simpler for me. Seen in the photo is the Ham-gadgets Pico Keyer and the N3ZN tiny CW key I picked up at the Huntsville Hamfest. Once I get all the parts out of the case I close it up and use it in the passenger seat for the hard surface to place the radio on so it is out of the way while I use the center armrest for logging and sending CW.

Here you can see how simple the connection scheme is when running Hamstick antennas, there is no tuner or interconnecting cables, just the RF choke to the coax, the power cable (I plugged into the truck’s cigarette lighter port today) and the CW key cable and nothing else is needed. Simple is king here and it also makes setup fast. That is another reason I like using CW instead of other digital modes with this radio as well as my other radios to this point. They all need a computer and a sound card to get them to do digital modes (other than CW) and I normally don’t have a ton of time for all that setup and getting it going. CW is on the air really fast, like SSB. You can also see the silent fan mod I did a while back (there is a blog post showing what I did) and I really like this mod as it eliminated the fan noise entirely. I need to make a screen to protect the fan though, that is still a project to be done…

You have seen this view shown below in the past, but I included it today since I got the moon in the photo too… lol. I do like the system I have built for activating a park with a hamstick, it is really fast to deploy and when I do a rove, I simply coil up the counterpoise wires and lay them in the truck bed. pull off the radiator from the QD base and lay it in the bed of the truck too, unplug the coax and coil up the portion to get it inside the truck and I am off to the next park. The antenna mount can ride in the receiver hitch easily enough so it is not an issue. This sounds like a lot but it literally happens in two minutes tops and I am driving to the next park.

Another thing I did today was hook up the inline power meter. Now I don’t remember why it only shows 8.9 watts of output. I had the radio set to 15 watts forward power so I probably took the photo after I let off of the key as the amp hour meter doesn’t clear till you disconnect it from power. I don’t remember if I had it in tune mode or if I was simply sending dashes. But what I was looking for was the total amp hours of use, this tells me if my little 8A/h battery would hold up to a heavy activation. From this meter reading it will. Now remember, this is with the radio set to 15 watts too, so under a normal activation of 5 to 8 watts, this would last for many hours. Today I went for two hours and got 70 contacts in the log and only used 3.68A/h and that makes me much more confident in using the smaller battery for activations now. I had my concerns before but now I don’t. Another point here is that I normally try to add something else to the activation that has to do with information gathering so I also learn something that I didn’t know before, today it was the amp hour info.

So I get to the park and take my time and listen to the bands a few minutes once the rig is installed and decide to start on 40 meters as the noise level was really low today. I get on the air at 13:25 UTC (9:25 local time) and start calling CQ… It didn’t take long to secure the activation and I had not left 40 meters! I don’t get on the lower bands too often as I am not at the park at night when the bands are less noisy so I don’t get the hams in the closer states like Tennessee or Georgia, it was really nice to get some of those states in the log for a change. Hanging out on 15 and 17 meters nets much more distant stations so I have to remember to come back to 40 every once in a while…

I then move to 30 meters for a little while to see what I could do there and work several more people on 30 meters in about ten minutes of operating. 30 meters at this park is a crap shoot to be honest, some days it is quiet and some days it has this intermittent computer noise that just shuts the band down, today the noise was nowhere to be found to my delight!

Then…I…got…on…twenty…

First off, who doesn’t work Bill (K4NYM) if he is booming in to your station and for a Park to Park no less? So I hunted him before setting up on frequency. It took one try, he is an amazing operator and I aspire to operate as efficiently as him some day.

Things take off once I park on a frequency and start calling CQ. I promptly work a page and a half of calls then I get the one you see below. Not one to brush off anyone calling me, I take the time to have a nice QSO with him as he is working on getting on the air with CW and is having to do head copy only…I later learn… So I take the time to write down what he is sending so I can read it and respond when it is my turn. Turns out he is just now getting back active in CW after taking a long hiatus from it and also, he cant see, hence the head copy only. Talk about a person with conviction, he never gave up. I was so glad Justin called me and feel honored he felt confident in me enough to throw his call into the fray of POTA not knowing what would happen. That took guts.

Once we finished our QSO it was back to the POTA game in full swing. I struggled with one thing today more than anything else… stations zero beating me. It never fails, I get two or three stations that due to modern technology, will zero beat me perfectly. This in itself isn’t a problem and is really the most efficient QSO to have in CW, but what happens is that those two or three stations melt together into the one single tone and it is unintelligible. So If I don’t pull you out on the first try, move up or down 30 to 40 hertz, This will make you off frequency enough to sound different and you wont blend with the other stations and I will get you on the first try, this is an old contesting trick and by golly it works, I will have one station that stands out and is clearly definable and the rest is this one huge tone. I never really understood it till I was an activator trying to pull one call out of the mayhem, then I got it. Now when I hunt I leave my XIT or Transmit Incremental Tuning on and set 40 hz high just for this reason.

Once I hit 70 QSOs today I had been on the air for two straight hours so I went QRT and shut down the radio. It was a great activation and I really enjoyed working with a new (relatively speaking) ham on building his CW skills back up to what they were. So till next time get your radio out!!!

72

WK4DS - David

The Penntek TR-35 goes QRO with the OUTCOM OPA-202 Amplifier

You have heard me mention KG4WBI a few times in this blog. He literally has what seems to be a veritable museum of vintage ham gear.

Well in today’s episode of “what oddball, ancient but yet working piece of gear is he going to pull out today” he hands me an amplifier. It is the OUTCOM OPA-202 to be exact and it has a feature we are really interested in. It doesn’t have a keying input which means it is RF sensing only. This stands to reason too as it also takes 1-10watts of RF energy and turns it into almost 175 watts on the output. At least that is what the literature says.

Here is my current test setup for gear, I have a coax stubbed out to the shack bench plus the Astron has powerpoles on the front making for an easy temporary setup location.

Made in copious quantities at what appears to be the end of the last ice age, the OUTCOM OPA-202 was a ham radio amplifier that was designed for 40 meters to 10 meters. Now your going to say, David, I know that…it says that right on the front with the 7-30mhz. I think this was done to target both the CB genre as well as the amateur radio group but I dont know for sure. What is odd is the literature below shows that it is rated for 80 meters too. Who knows what the lowest band it will work on is… I do know it works on 20 meters and 17 meters though as I tested it on both of those bands with my Penntek TR-35 transceiver.

The next thing you will notice is the selection buttons are labeled only for voice modes. This is another marketing ploy to help sell these little power houses. The buttons are actually power output selectors and depending on the combination you can theoretically get up to 175 watts out of this thing. Seen below I have it set to “SSB” mode which turns out to be semi break-in keying and 80 watts out. There are 4 levels depending on how you set the “AM” and “SSB” switches, but it also limits the amount of energy/duty cycle depending on the mode. It actually lists CW in the modes and the output and such, hence I am not running it full tilt. It also has protections built in to keep the over zealous operator from working it to death with long winded conversations. This particular unit seems to produce full break in keying if you select “AM” and semi break in with “SSB” modes. Probably due to the style of transmission coming with each of those modes. AM will produce a carrier the whole time you have the radio keyed and SSB only when you talk. To smooth out the relay action in SSB they have added a 1000 microfarad capacitor and a 470 ohm resistor to the relay keying circuit to keep it closed in just a little longer when SSB is selected so the relay wont sound like a machine gun. Another switch right beside the power switch is the pre-amp switch (REC AMP) which turns on a receiver pre-amp for weak signal work and it actually performs really well. I used it quite a bit and liked in particularly well.

So Roger wants me to … as he puts it… play with it and see how it works. This is his way of giving me something new to write about. LOL Once done, his plan is to integrate this amp into a vintage Field Day kit. This would be a neat little addition to his early Argonaut 2 that he has since it is only 5 watts output at full power.

In the flyer above, the bands go all the way to 80 meters but the unit we have doesn’t list 80 so they must have updated the specs over time for some reason.

Back to the RF sensing part, the reason we want this is it simplifies setup at field day for us. If we want to use QRP power for our ops then we can but if the bands just aint cooperating then we can easily add some power and get things moving. Our goal has always been to see if we can get on the air with QRP first and most years we are successful but occasionally we are not. So this allows us that leeway to be able to add output power as needed easily and with literally any radio we connect to it. We like this design so much that we are going to hijack the RF sensing circuit and see if we can copy it for another little amplifier he has that doesn’t have current sensing. We think it should be a simple thing to build a little project box that goes between the radio and amp that has both coax ports, a 12v power cable and a simple keying cable coming out to connect to the keying input on the amplifier. We even considered using the little 4 pin Amphenol plug so it will look “official” when we build it…hi hi.

Things of note about this amplifier, it has no fan, so it is static cooling only with the enormous heat sink that is attached. Don’t forget you have this monster of a heat sink when you install it in your car too as it will be on the bottom and I am pretty sure it needs ALOT of air to be able to keep it cool enough at full power. Another thing is the meter on this unit is frosted over, but no worries as when you key the radio, a light comes on behind it and lights it up just enough to be able to read the milliamperes DC that are flowing…somewhere…lol. Actually, from what I gather, the meters in these amplifiers were terrible and replacement was pretty common so apparently someone replaced this one and didn’t switch out the backplane so the meter would read right. It is supposed to be some sort of SWR meter from what I can gather by reading the manual.

Lastly, someone has replaced the power cable with new wire…and left the bulkhead connector off so I will add one back if I can find one before returning it to Trey. At least it is fused on both the +13.8 as well as the ground lead. That is nice when the insulation breaks down at the sheet metal and decides to short one of the wire.

Anyway, all that said, his museum piece actually works as I made several CW contacts with it using my Penntek TR-35 QRP transceiver. The little radio has plenty of drive for the OUTCOM OPA-202 so I was easily able to get 80 watts without issue and this was plenty to work one ragchew QSO as well as several POTA contacts. The system looks a little messy on the bench but will quickly clean up now that I have proven it works. So until next time, 72…errrr…73

de WK4DS

Counterpoise testing during a POTA Activation

Today involved some experimentation as well as a POTA activation. I tested some changes to the radials I use on my hamstick system out of curiosity and came away with some interesting results. Read on to see the AAR and the results of this test.

Today was supposed to be a quick little activation and then I was going to do a few other things, but plans are made to be changed from what I can tell as the bands were doing well for me and I stayed longer than I planned. But then the sun can bring that full circle as you will see below.

The operating position today shown above, was on top of the hill at the frisbee golf course and on the bed cover of the truck. Turns out that was somewhat of a bad idea. It just got hotter as the day progressed and the sun quickly came over the door I was using to shade me. This is what ultimately caused me to go QRT when I did as I was having a decent run on 20 meters at the time. It was just plain hot, with the sun seemingly cooking my right ear while I was working ops. I did enjoy working several ops today I have seen in my log before plus some that I have not. I even got a Canadian which is always nice.

This is probably the best image of my 40m hamstick and mount I have ever gotten. With the sun in the right spot, the whole antenna lit up well enough for the camera to get it. The setup is not actually mobile as it requires a counter poise to get it to work it’s best, but wow… it worked really well today, especially well today actually for some reason. I can hear surprisingly well on these tiny HF antennas too. I own three different brands of hamsticks (covering 40, 30, 20, 17 and 15) and can not tell a difference in any of them as far as how well they work. They all just work really well.

These two photos tell a story about what was happening at the location today on 30 meters. When people talk about having RF noise at a location, this is what it looks like on a radio that doesn’t have a waterfall display. The photo above is what the noise floor looked like when the RF noise was not present and the bottom image is what it looked like when it started up. It also was not constant, but appeared to by cyclic in nature as it would spool up and would just be some sort of hash for about 20 seconds and then it would just go away for about 30 seconds maybe longer. I would be able to work one contact and then it would come back and if the hunters were not transmitting with an S9 signal, I couldn’t hear them. This is really frustrating and is one of the reasons I don’t activate 30 meters more than I do. But so it life and how much fun would it be if we never had problems to solve? It would get pretty boring pretty fast… Even with this RF hash coming in and out, I was still able to get 9 calls in the log on 30 meters today so I count that as a win anyway.

The next thing I want to share about today has to do with the antenna system I was using. I have made tuned radials for all of my hamstick except the 15 meter unit (I have not deployed it yet, but soon I will.) I went to a lot of trouble to tune these radials too, with a ton of time at home working on this. Well, it turns out that I didn’t need to do that for the 30 meter hamstick at all. I deployed my nanoVNA today and did some measurements on the hamsticks to confirm nothing has changed with them and figured out something just out of curiosity. Seems that the radials for 40 & 20 meters work just fine on 30 meters too. This means one set of radials for all three of those hamsticks. Next outing I will take the 17 and 15 meter hamsticks and tune them up and see if the same radials will work on them too…fingers crossed. I am always looking for ways to simplify my station setup and the radials has been one of the slowest things to deploy of all the gear for POTA with the hamsticks. So if I can get it down to just the two radials and not having to remember the color codes for them and such I will count that as another win in my book.

The above photo shows that the antenna is fine on the 20 meter CW section, even though it is technically low on the best part of the chart, it is only 1.188:1 where I normally work on the 20 meter band. Well, knowing that, below is what it looks like on 30 meters with the 40/20 meter radials instead of the tuned radials I made up for just for the 30 meter band. Pretty crazy huh? Looks almost identical to the 20 meter chart and even almost matches the 20 meter SWR value. I was blown away by how good this turned out and to think I have never even tried it before today… Another thing I noticed about hamsticks in general is that they act like bandpass filters across the HF spectrum, I did open up the range on the nanoVNA and it does have other nulls IN THE VHF SPACE, but each hamstick has ONLY ONE spot they are resonant at in the 0 - 30mhz spectrum. No multiple harmonics like the EFHW, just one really deep SWR null is all you get. So plan accordingly, but to be honest, it works really well so I am not going to complain. I think this might actually work as a band pass filter but have not had the chance to test it yet. Maybe I will set this up at winter field day and see what it sounds like there. That should do it.

Here is the log from this activation and the signal reports look good for a mismatched antenna on the trailer hitch of my truck. I was using 15 watts though so that might have helped some. I have been sending with more power lately to just play with the Argonaut to see how hot the heat sink gets at various power levels and on CW it barely gets warm at all with 15 watts of RF so I am really happy with that. I am doing this test since i changes the fan a while back to reduce the fan noise as the factory fan is quite loud. I have a blog post showing what I did with this if you are interested in that.

All in all I learned something new and had a great activation at the same time. So till next time go get your radio out and make some contacts on it!

Testing a new antenna AND CW key during a POTA activation!

I decided to pack up the Argonaut 5 and go activate Cloudland Canyon today to get some much needed air time and wanted to try out my new POTA key that I picked up at the 2023 Hamfest in Huntsville a little while back (actually you will be reading this in the future as I picked up the key last weekend but so is the life of a blog post) So follow along and look at what I found out today while making a few contacts from K-2169.

I also decided to do some testing of the Reliance Antenna Bugout 40 EFHW I had bought from N3VAN who was making them and selling them on the QRZ forums. The antenna looks really good with lots of attention to detail in the construction. I have never used an antenna that doesn’t have radials or a formal counterpoise at all. This one uses the coax shield as the counterpoise so, in theory, you don’t need a counterpoise at all. (Come to find out, you can bend the rules of EFHW antennas if you do add a counterpoise) I strung it up in the air between two trees out near the bluff at the park. This may have doped my results, but I am doing a test anyway so why not, right? The far end is about 30’ in the air. The near end is about 12’ up to the transformer and I dropped a 15’ piece of coax down to the radio. Done. Well, so I thought at least.

The far end is way up in this bright green tree behind my hand in the back ground. I am pointing to the end of the wire location in the tree.

Once I got the antenna up in the trees, I wanted to see what the plot looked like on the nanoVNA so I plugged it all in and this is what I got. The antenna is technically slightly long and is a little below optimal frequency on this day and rigged like this. I am not going to trim it at this point as I want to see what it does in other kinds of conditions like the winter and maybe right after a rain when it is still wet or maybe where it is set up over night and is soaked with dew. Even though it was off frequency a little in the configuration I had it in, the SWR was well within safe limits for operating any transceiver. I didn’t have a 2:1 SWR at any point when I was testing a particular band and that if fine with me if I don’t have to carry a tuner with me. There was a side bonus to this setup too, for some reason with the whole antenna elevated like I had it, it was giving me a wide coverage (read that as a low q) in the bottom of the 10 meter band. So low in fact, that it was within usable range even on 12 meters without needing any sort of a tuner! That is 40,20,15,12 & 10 in one antenna with zero mods needed. That is winning in my book.

This was the plot without anything other than the 15’ coax going to the common mode choke.

Now get this, I added a radial to the system, but in an unusual location. I put it on the end of the coax on the connector next to the common mode choke right next to the radio and just stretched it out over the ground. This length of wire was 9.5’ in length and when I did this, the plot changed a lot. I lost the 12 meter dip but picked up a much broader area between 20 and 15 meters to the point that 17 meters was below 2:1 SWR at this point. This means that if I add this simple piece of wire I now have a “no tuner needed” antenna that covers 6 bands! Almost everything is usable…sans 30 meters, so I am really happy with this antenna. The next time I set it up will be to test it as a sloper like it would be used if it is a portable setup and I had only one tree to rig it to. Then we will plot it again and see what I come up with. I am curious to see if the frequency of the dips changes with the relation of the end of the antenna to the ground. I dont think it will but RF is a fickle girl…lol.

This plot is the aforementioned setup plus a 9.5’ length of wire tied to the coax connecter at the common mode choke.

This much wire is all that I needed to gain access to 17 meters without having to carry an antenna tuner with me, this is very liberating to be honest. Just adding a small radial to the system makes this super easy to use. The Reliance Antennas 40m Bugout EFHW comes with a winder to store in on as well as a carabiner clip to connect the far end to the cord. The transformer end has an eye bolt that works well for a hoist point to raise the other end of the antenna.

I next setup the Ten Tec Argonaut 5 radio on the table and connected all the stuff to make it work. Once it was powered up and ready, I plugged in the star of the show, my new N3ZN CW Key. He builds some really nice keys and I have walked by his table at several hamfests recently and today I decided that it was time to give one a whirl as they say. So I chose the smallest one he had at the show since I wanted it for POTA activations. The plan is to keep it in the Argonaut “GO BOX” that I built last year. It took me two trips to the field to learn to use it properly too. Since it is so small, if you have a heavy hand when you send it will move around a lot on you. The trick is to set the action light enough that you just have to touch the paddles to send the code, this way it is a light operation and the key stays put on the table like it should. These keys come with the cord hardwired to them so you cant buy a simple aux cable and plug it into the key, but it didn’t cause me any trouble so I don’t mind it. The installed cable is high quality and I have no doubt that it will last a very long time.

Once the antenna was squared away and I had my 17m “element” nearby, I was ready to crank up the radio. The new key plugged into the keyer I recently acquired from eBay and we are off to the races! Or so I thought as it turned out that KJ4BAD happened to be walking by and stopped in to see if I was doing POTA and we had a great chat for about 10 minutes or so about all things radio. I always enjoy running into other hams while out at a park.

I really like the Ten Tec Argonaut 5 radio, it has almost all of the CW functions that I use are on the surface. There is a could of things that you hit a button and then make the adjustments and you are good to go. The other thing that is great about this radio is that it has 20 watts of transmitter power. This is awesome when the bands are not as good as they were back in the winter. Also the DSP filtering works surprisingly well. It is also really good with other modes, but I just use it for CW… I might make a cable at some point to put the key into the front socket instead so it is simpler to connect the key. You see the mic key will key the radio so that means my little memory keyer will work in that socket. Who knows when I will do that though…

After we finished chatting I settled in for some POTA therapy and dialed around a little to find 15 was open with a bunch of stations on the air. I setup and start calling and you can see in the log that I only made two contacts before giving up and moving to 17 meters where I usually make several contacts but today I only netted one. Things were looking pretty dismal till I went to 20 meters. Once on 20 things turned around for me. I fairly quickly got the activation and proved out all the gear I had brought that day.

This photo shows where I would place the extra radial on the Coax connector. The coupling between the common mode choke and the feedline made for an easy spot to add it. I simply stripped the wire back a little and twisted the wire over this point. Simple as that. The easiest mod I have ever done to tune my antenna to another band in the history of ever.

This was the view I had today while operating, this is why I like POTA over other activities. The view is epic. So there you have it. My POTA “test and tune” trip in a simple blog post. Until next time, 72.

de WK4DS

DX QSL Cards are Awesome!!!

I once did 100% QSL with paper cards… those days are long gone though. It turned into this huge project to keep up with them to the point that I spent more time working on the QSL cards than I did on the air.

It was at this point that I decided to alter my strategy for QSL management to the one I am using currently. This strategy led to me getting this letter in the mail.

My current (and sustainable as well) process is to cherry pick the QSOs I send cards to. I have some criteria that I use though.

• Ragchews almost always get a card. If the other op doesn’t QSL I wont but usually I send one for this.

• QRP contacts whether from my home or abroad will also usually get a card. To clarify that is they are QRP. I work it so much that I dont use my radio as a factor. Same exclusions as above here too.

• DX if it is a country I have never worked before. Actually this criteria is a mandatory QSL…as long as they do QSL.

• If I just want to is the last one.

So back in July, I did a POTA activation at K-2169 and used my Ten Tec Argonaut 5 transceiver for the activation. On that day the bands were in great shape and so I start On 15 meters and after a while moved down to 17 meters to get a few contacts in the log. I felt pretty confident 17 would be good as I had already worked two DX stations on 15 meters. Albeit fairly close to home, but they were still DX none the less.

Well, I work several US hams and they are coming in sporadically but then I hear this station that is clean but weak. I thought at first I had missed the first letter of his call as I heard a J next, we went through the “on air gymnastics” of asking for the call again and when I got it, I was blown away to realize it was a Japan station!!! I had to send him a card! So I write one out and check his QRZ and he does QSL, so threw in a few green stamps to help offset his costs and off it went into the mail. Today, I got my reply…

In the photo above you will see three cards, one is handwritten, one ís typed and one is a different card altogether. The odd one is an extra card he sent that was his old QSL. That is awesome to me. I love getting these in the mail. If you will notice he has a 4 element beam so that combined with good band conditions allowed my 20 watts to reach him in Japan.

It is interesting to me that I will get so accustomed to hearing the 4 US call letters first that when I hear one from somewhere else, it “breaks my brain” for lack of a better term. I am listening so much for A, N, W & K that I completely miss the other letters most of the time. I actually can catch V calls pretty good now as I have worked many since starting POTA activating regularly but it is the exception. This has prompted me to listen on the bands more to try to hear DX calls and not lose my marbles when I hear one… lol. I copied a Swedish station the other day first try and was kinda stoked so my practice is working. But this is a side effect of being a US amateur working a lot of POTA in the eastern USA, you do get accustomed to hearing certain prefixes a lot (or at least I do). I have a bunch of those stories if you want me to recount them at some point…

Do you have any odd idiosyncrasies that you run into while operating on the air? Let’s hear them! Till next time 72

de WK4DS - David

A couple of quick activations testing the antennas

The past couple of days have been busy and there was still time for a couple of quick activations along the way.

First stop is the Estelle Trailhead on Crockford Pigeon Mtn WMA (K-3742) over in LaFayette GA while coming home from visiting with my mom. This is actually a new park for me even though it is only 15 miles from home by road… I dont know why, but I have never activated it for some reason. The Estelle parking area is fully within the WMA boundary so it was a simple matter to pull in, get parked out of the road and setup a radio in the shade for a little while. Today saw the Ten Tec Argonaut 5 again as this radio was the one in the truck at the time. It is also one of my favorite HF radios at this point. It only lacks two things to be the perfect radio, an SWR meter and an internal antenna tuner…but I digress.

I said that I setup in the shade, but there really wasn’t much to start with…lol. I did get lucky and a nice cloud moved in after a few minutes and helped keep things cool. I don’t like to let my radios just sit and cook in the sun if I can help it and will go to fairly great lengths to prevent them from getting hot. This is what you see here. The shade was just wide enough to protect most of the radio from direct sun so it didn’t get very hot before the clouds moved in. On top of that the tool bag is shading my battery in this photo too, I didn’t want it to get too hot either…haha.

I started on 15 meters today as I finally have a 15 meter capable radio and antenna too! Well the RBN showed 29dB for me! That is crazy good for someone with 15 watts under their belt into “7” land. But try as I may, there just wasnt that many hunters on 15 meters for some reason. I did get 3 QSOs in the log while on 15 meters so all was not lost. Then I moved down to 17 meters and did quite well there, picking up several more contacts. Then I finished out the activation on 20 meters which is my backup if I need to get my 10 for the activation. 20 never seems to let me down either as I can almost garuntee at least a few contacts there.

So after getting the activation, I wanted to experiment with the antenna system and see how it would work on the drive home. Turns out the 20 meter hamstick without radials has worse SWR than with them, going from 1.15:1 up to 1.7:1. Who would have guessed? LOL. This is not a real problem though as this is still well below what I consider useable SWR. As long as I can stay below 2.5:1 I will operate. That is the upper limit though and I will work on the antenna a good bit to get it down but if nothing helps and I have 2.5:1 SWR, I will try it. The radios can handle anything below 3:1 so I set my personal threshold below that… I know some people wont use their gear if isn’t almost perfectly 1:1, but I have come to realize that it isn’t so important and the signal reports speak for themselves.

On the drive home, I start hearing this REALLY strong signal booming in to the Argonaut 5. The above photo shows what the signal level coming into the radio was 20 over S9, and remember that the Argonaut 5 has a S meter that doesn’t like to give out good signal reports. So I start working on head copy on the drive and finally get that it is W1AW/0 in Colorado and he (or she) is working as a POTA park! So I do what any sane POTA hunter would do, I pull over at the New Salem Firehall and work them mobile! WK4DS/M got into their log!!! WooHoo!!! So at the bottom of the logbook page you will see where I logged the hunter contacts on this trip since I was not at a park when I made these contacts.

New Salem Firehall parking lot was empty and worked great for getting my hunter contact on the drive home.

As a side note, I finally made the hitch pin (shown below) for my antenna mount so I can use it for the rover program without having to pull it off the truck and stow it between parks. I am working on reducing the setup and breakdown time at each park as I am going to attempt a 10 park rove and this will take planning to make it happen. Things like this can add up on the rove to make it take too long since the drive time from one park to the next will be the biggest time eater of the day. So if I can find simple little things that I can do on each stop to save time, I can make the most of the activation.

I made the main pin that holds the mount, but I simply bought the little pin to lock it in place. Sometimes it is smarter to buy a part rather than spend the time to make it. The main pin was easy enough to make from scrap shafting material. but to make the keeper pin would have taken more than the 3$ it cost in time so I opted to simply buy it instead. To be honest, it would have probably been smarter to buy the main pin too, but I had a scrap piece of round and time available on the lathe so I just carved one out right quick rather than drive to the store to buy one. Another plus is that I could make it like I wanted which included adding the handle to the main side so it is easier to pull when breaking down the system. On top of the pin making, I also opted to add an extra set of holes to the antenna mount so that the pin can be left in for simple POTA activation days where I dont have to pull the pin to simply setup for a single park. This allows me to just stick the mount in the hitch and use it like I have been and take it down when done so I can stow it inside the truck bed when not in use.

The next park I went to a couple of days later is the Chickamauga National Military Park. K-0716. This park lies in two states, so today I opted to activate the Tennessee side of the park. This location is easy to access as it is literally on the side of the road. This is why I like this location and hate it at the same time. The location is called Eagles Nest and is part of the military park completely within the park boundary.

K-0716 presents me with a quandary. This “shack” position makes for a comfortable operating position but the road noise is really bad due to the proximity to the road… I have used headphones here before and that seems like the correct thing to do if I operate here much more. I am going to go ahead and get my repeat offender for activating this park. I am already half way to this award anyway so why not? Ha Ha… Another thing that surprises me is that there are some fairly large trucks to travel up this narrow and winding road to the top of the mountain. Like large d4livery trucks kind of large, I guess it is normal, but it just kind of caught me off guard to see such large trucks going by while I was there.

The radial situation is unique here too, since it is on the shoulder of the road, I have to put both radials on the same side of the truck. Whenever I do this, I always get out the nanoVNA to see what this has done to the SWR plot. As usual, it did affect it but not by much. I was surprised to see that on 15 meters it needed both radials to get a decent SWR before I was happy. So I get it setup, spot myself, start a log in HAMRS and start calling CQ. I finally net a couple of contacts on 15 meters, but there are not many hunters even though the band was open. It did have some fading, but it was fairly strong anyway and could easily support use, but people were not there. So I moved down to 17 meters. Once on 17 meters the RBN (Reverse Beacon Network) picked me up and showed the strongest signal report I have ever seen for one of my activations. 42dB is insane! I have never seen that and this was with 15 watts no less. So people MUST be on this band, right? Well no, it seems that all the people on HF were down on 20 meters having a grand old time without the few of us up on 17 meters. I added 4 more QSOs to the log with one being KJ7DT who followed me down the bands working me on all three on this day. To me this is awesome as it shows the propagation for all three bands was really good as he is in Idaho which is almost 1800 miles from me.

So I finally decide to join in on the fun on 20 meters and QSY down with what seemed like the rest of planet earth and secured the activation in short order. Getting Paul - KJ7DT a third time on this day and Keith WI0S twice! Both of these calls have appeared in my log on numerous occasions. These are some very prolific hunters and I just want to thank them for being there to hunt like they do. They are what make activating parks fun. With 13 calls in the log I officially had the activation so I packed up as it was getting close to lunch and the road noise made it very hard to hear as well and headed into Chattanooga to go have lunch with the girls.

The clip board has made a huge difference in operating ease for me. I can now not worry about the wind turning the pages and it gives me a hard surface to work from no matter where I am. This alone helps a ton. As seen here, I am able to lay the keyer and the key on it as well as log. If you still paper log this is a very handy addition to the POTA kit in my book. Yes, I still paper log. I have had too many computers where they crash unexpectant and you have to reboot the machine and wait for it to get back up and running to trust it with my only log of an activation. The paper notebook gives me a durable backup to my phone logbook that I run at the same time.

Side note about how I log… I will run HAMRS in parallel to my paper logs and if the activation is going kinda slow, I can log both at once and keep the electronic log caught up in real time. This is a recent thing brought on by me wanting to not have to set aside time at home just to transcribe the log so I can submit it online. I found that a lot of my activations are slow enough to permit time to log the QSOs while I work the activation and not have to do it at home. So if things speed up and I cant log both the paper and electronic, then I always default to paper and the battery never goes dead in paper logs nor does the app crash… Then when things slow down, I will let the keyer send CQs and I will catch up the electronic log while I am calling so I don’t waste that time just sitting there waiting on an answer. This works really well and I can normally email the log from the park before I leave so when I get home I can simply upload them to the POTA site since it wont let me upload from my phone yet…

Here is something else that a lot of people that don’t do field ops have no idea about. A carrier with a bunch of backup equipment is a must. Everything in this bag has been used on an activation in the last few months in one way or the other. Notice there is power cords and spare coax and three pens are visible on the side, this is something that you quickly learn, things break, pens dry out, you run out of paper, all of this is things you have to prepare for before going to the park and the only way you learn this is from doing it. I can preach to the ends of time but until you have to end your activation because your coax connector came off or the center conductor broke on the coax or your antenna mount breaks, you wont prepare for it as a contingency. That is just how it is…Another really handy tool to have is a Leatherman multitool of some kind, brand isn’t important, what matters is that you have one, I don’t know how many times I have used mine to save the activation some how. Totally worth the price of admission in my book.

QSO maps are awesome, I have KJ7DT in the log on all three bands today so his one pin is actually three. Just like I have WI0S in the log twice so his pin represents two contacts. This is neat to see though as you get a visual idea of what the bands were like on this day. If I studied space weather more then I would be able to corelate the data so that it would be more meaningful, but like this it really doesn’t tell much other than skip distance for the bands I used. That is about it but it is still fun to look at them nonetheless.

So this is what it looks like to activate two parks on two different days and how the setups vary for each one based on the conditions for each location. Next time I will carry headphones for the one by the road so I can hear better. Till then, get your radio out and make some contacts with it!!!!

The weather can be fickle…

We went to my local park (K-2169) to do a little POTA and to enjoy the nice weather there.

I setup at the canyon rim today in the shade and got my rig setup in my usual tree and everything. I look on the web and the MUF showed that 17 meters was open and I dialed around and did hear stations so that was promising. I tuned up the antenna on an open frequency and started calling CQ…and called and called …and called. No one answered my calls for something like 10 straight minutes. I even had someone respot me once but never heard anyone on the air

I even took a few minutes to confirm that the Ten Tec Argonaut 5 and the Ten Tec 277 Antenna tuner were set correctly with my nanoVNA. They were in fact set correctly…so I just wasn’t being heard on 17 meters. Probably because I am only using 15 watts from the Argonaut. Maybe because the band sucked like a Hoover vacuum cleaner that day, who knows…

This antenna tuner is the Ten Tec 277. It has options to connect a COAX to an antenna, a balanced line to the antenna and even a random wire input (which is what I was using on this day) The variety of connections is what led me to acquire it in the first place, I like the ability to use it with any antenna I have and it works quite well in that role. It is easy to tune and the SWR meter works well too. I don’t use it as a traditional SWR meter though, I use it to watch for changes in the antenna system. If the SWR starts to climb then I know something is changing and I need to look into it, I have had things like the counterpoise wire break in the crimp lug before and not realize it due to it being inside the heat shrink tubing and this meter showed it to me. It also works for tuning purposes if I forget my nanoVNA as well.

My nanoVNA kit is almost entirely adapters and the tiny little VNA over to the side. I love this device and wonder how I got along without one before.

Anyway, back to that activation on that day. Since17 meters was apparently turned off by this point, it was with a heavy heart that I QSY-ed to 40 meters. I tuned up and started calling on this band and it didn’t take long to get someone in the log. After getting quite a few “locals” on 40 meters, I shifted my focus up to 20 meters. For me with my low antennas in park activations I will normally get closer states on 40 meters and more distant stations on 20 meters and higher. That is one of the reasons I like 17 and 15 so much. When they are open I have had great performance with DX stations. If you look at the map below, the close in contacts are all the 40 meter contacts and some of the closer ones are 20 meters.

I just love maps like this one where there is this one lone QSO way off.

It was about this time that the storm clouds really started to look ominous on the western horizon. But they didn’t really seem to be moving closer so I kept going. Well, 20 meters was open is all I can say. My very first QSO on 20 meters was with G3WPF in the UK! I actually thought he was an American station and I was missing the first letter so I had him repeat it a couple of times…lol. I am glad he didnt give up as I figured it out finally and got him in the log. What an awesome way to hop on 20 meters with! DX right out of the chute!!!

As can be seen from the logbook, I had a decent run on 20 meters before two things happened at basically the same time. The storm started to move into the area, and another ham tuned up on top of me and I couldn’t hear stations anymore. I chalk it up to them not being able to hear me as I was only 15 watts into a random wire pretty low to the ground. Anyway, that was enough to get me to call QRT and pack it all up before it got wet.

Until next time I hope to hear you on the air!

de WK4DS 72

Overcast POTA activation strikes gold!

So today was a good day for POTA. I did some small work related items, grabbed the Ten Tec Argonaut 5 and headed to Cloudland to get an activation in before lunch. Before I even setup on frequency I was dial-ing around on 17 meters to check the band and found G3VBS calling CQ with no takers! So I figure, why not see if he can hear me… turns out 20 watts was plenty to make a contact with England and we had a great chat for quite a few minutes with only a little QSB.

Today I setup at the frisbee golf course parking area as it is the highest part of the park as well as the quietest RF wise. The lower lot has a nicer view but with the proximity to the campground and so many more people in general, it tends to be noisy comparatively.

Something else I like about the upper lot is I can either deploy the setup in the photo above or I can string a wire in a tree as well. Rigging the hamsticks in the lower lot is more difficult to say the least. So I was a little worried about the impending rain that was on the radar, I normally use the setup you see as I can sit in the truck and operate even in the rain. This is really nice as even inclement weather cant stop my POTA activations! Haha.

Well sure enough when I got home, it started raining so I made a good call here.

I did setup on the bed cover though, which is a little exposed but I figured I could move it into the truck pretty fast should it start to rain.

Today’s radio is the Ten Tec Argonaut 5 which is a wonderful little portable HF transceiver. It is larger than the TR-35 but it also has multiple modes and has every HF band available as well. Today I started on 17 meters because… why not? And that is where I heard G3VBS. I figured I would secure the activation with ease after having a great QSO with the UK. I couldn’t have been further from the truth. I only made one more contact on 17 before giving up and moving to 20 meters. Once on 20 meters things started to pick up for me.

There were a couple of pretty strong pile ups at times and it was fairly difficult to dig out a sinlge call. Mainly because most of the stations were zero beat with me. This makes all the signals turn into one large tone and I get garbled info. Luckily, I have learned a couple of tricks around this and can work with most people now. I will simple call W? Or if I get part of a Canadian call, VE? You get the point. This is a tried and true trick of pile up runners (did I just make up a new term? LOL) around the world. When you cant make out anything, just ask for the most common prefix you know and someone will reply. It worked well for me today as I was able to break apart the pile up and get every one into the log that I could hear. I even worked 4 or 5 stations after calling QRT as they were asking and I had time. I ended up with 36 QSOs toward my day as I had one dupe so it was a great day for POTA. If you want to know more about POTA just give it a google search and head over to their website. Until later, 73 de WK4DS

Component failure sucks…

When things dont go right it can be frustrating but when things are like my activation recently they are downright demoralizing…

So I had an evening free and wanted to do some POTA so I decide to setup in the truck with my hamsticks … since it is faster… you know since everything is ready to go. Little did I know what I was about to get into.

So I goto the frisbee golf parking area and get everything out to do an in-truck activation. This is how I operate if it is raining and has worked well for me in the past. I just tape a “rain shield” to the coax connector made from a peanut package with both ends cut out. Haha, reuse at its finest. But today, I didnt need it since it was not raining.

Next I break out the Ten Tec Argonaut 5 and my N3ZN cw key and connect it with my HamGadgets PicoKeyer and I am all set. Another thing with today is I planned to activate with my 8Ah LiFePO4 battery to see if it can handle an activation with the Argonaut 5. I have my inline power meter this time so I can monitor the voltage too. I also can monitor Amp/hour usage but completely forgot to do this since I got wrapped up in other things. I setup this kit in the cab of the truck as you see so that I could sit comfortably while being in the truck. This works really well when I am solo, but gets tougher if I bring someone with me. As you can see below it was up to almost 3 Ah by the time I took this photo. I wished I had thought to get a photo of it at the end to have that data. I guess I will have to do it again… lol.

But before all this got started I connected my antenna and wanted to check the SWR before starting as I have been experimenting with the radials some here lately and have learned some interesting things about them. I get out my nanoVNA and connect it to the antenna and it shows like it isn’t there…at all. I mess with the VNA a while and try to see if it might have a loose adapter on the VNA or if the calibration might have been done wrong, which I found not to be the case after calibrating it again… Nothing in the VNA was wrong, so I get out of the truck and inspect the antenna and it looks right, nothing is out of the ordinary. I go back and get my trusty little multimeter and decide to ohm the center pin of the coax to the shield to see what it measures, it should be open to the meter…it isn’t, quite the opposite actually, it is shorted. So I immediately go to the antenna and disconnect my brand new, reputable brand coax and check it with it removed from the antenna, it measures good now. Whew! That was close! I didn’t want my new coax to be bad right out of the chute.

So now that I am pretty sure it isn’t the coax, I turn my attention to the antenna. I remove the radiator and test the base to center pin and it reads shorted!! What in the world is going on here!?!? I look closely at the mount, which at this point has the BNC to PL259 adapter on it and nothing else and so I remove the top portion of the antenna mount to make sure water has not entered the plate where it passed through and has created a path with corrosion to the mount. Nope, not there, it looks perfect.

So I remove the adapter and the short goes away immediately. I reinstall it and it returns. I remove the adapter and check it and it measures fine and so does the antenna mount now. What gives? Well, I had a new adapter I picked up at the hamfest from the Wireman and I just installed it to see what would happen. The problem vanished. I tried wiggling the antenna and the coax and pushed and pulled on the adapter and the meter didn’t change a bit, all I can figure is that something in the other adapter is shorting when the adapter bottoms out on the antenna mount at the point where it gets tight.

This is what went bad. On the surface from every angle it looks perfect, but when tightened in place it produces a dead short across the antenna to ground. Don’t blindly think that simple things like this can’t fail. Obviously they can. I will be more diligent in checking my system routinely too. The Argonaut 5 has no SWR meter on it, which is pretty much the only thing about it I don’t like, so I have to use other means of monitoring the SWR. The VNA was that tool today.

Once that was sorted out, I was able to get on the air and make some contacts. Since I was dancing with the end of the UTC day, I figured I would start on 20 meters to improve my odds of getting an activation before the day flips over. The hunters came in clutch and I EASILY made the activation. Once I cleared all the calling stations, I QSYed to 17 meters to see what I could do there as the band was open earlier…before I found the bad antenna adapter…

Turns out 17 meters right during grey line to the west coast will net some cool contacts. All but one are from the west coast and that is always fun as I rarely get to work California due to noise on the bands. All in all, I netted 41 contacts in the log all before the UTC day ended. So it all worked out anyway. Moral to the story is two fold. The first one is to take extra parts for your system and two is don’t assume anything… this adapter looked perfect visually but did not work when installed. Have fun y’all and I hope to hear you on the air soon.

PS: Another perk to working POTA is things like these photos I grabbed of the clouds. You normally don’t see these at home in the house. If I had stayed home or threw in the towel on the antenna (which I almost did) I would not have seen these beautiful sunset clouds.

73 de WK4DS