Getting a quick activation in…

Today I wanted to get the whole activation on just bands above 20 meters. This means a lower QSO count than normal (most likely) and I am good with that. For me it is not about a high QSO count but rather time at the park (so long as I get my ten minimum of course…lol). So let’s get it setup and going. I only had two hours from the time I left the house till I had to be back at the house, so this pointed me straight to US-2169 since it was only a 20 minute drive for me. 40 minutes gone in driving only left me with 80 minutes to setup, activate and breakdown the rig, so I was in a bit of a hurry. I was really hoping that my usual spot would not be taken and fortunately it wasn’t.

Today also saw this little guy, pictured below, die on me. I went to check the SWR on my nanoVNA and it was really bad. It was so bad that it didn’t show the antenna to be connected at all, that is the worst kind of bad… So I start troubleshooting as this is eating my time and I was not wanting to lose anymore time than needed to setup. Well, I got lucky and as soon as I removed this from the circuit, the antenna showed up on the nanoVNA!.I just had to run without my usual common mode current choke in place, it could be worse, I could have a bad radio… Luckily I can easily get these from the internet without much issue. I also have a coax from ABR that has the ferrites on it but forgot about it at that moment or I would have simply ran it instead…

As of late, I seem to be operating from the truck cab more and more. Today was no exception either as it has a power cable hardwired, is in the shade (technically) and is easy to setup. I don’t want to just operate from here though so I am going to make a conscious effort to do things more diversified going forward… But for today, it was inside the truck so I could save time. Good thing I did too, the higher bands were…thin…to say it plainly.

So I start by hopping on 15 meters as the “weather report” looked good for the band today. Trouble is no one else was there from what I could hear. I looked and looked for a CW signal and saw nothing anywhere, I then called CQ for a few minutes to no avail as well. At this point I decided I would switch over to FT8 and get a few DX contacts in the log since this is where I usually do that… didn’t happen. I worked one person in Arizona and that was it! 15 meters was not doing anything today! Wow… what a reality check. I normally get a few, but just one is a new record for me here.

Well, once accepting defeat on 15 meters I begrudgingly moved down to 17 meters and found the band to be alive! So the MUF must have been 18.200mhz as I made a bunch of contacts on 17 meters in pretty short order on CW before switching over to FT8 to finish up the activation.

The park today saw a lot of activity and I actually had to share the parking lot with other people…I felt really odd having to do this. LOL… But really this location in particular is really good as it is in the middle of the lot which happens to be the least traveled location in the whole lot. There really isn’t anything that anyone would need that would require them to walk where I deploy the antenna. This is something that I look for now when activating a park. It is real important that you don’t leave a bad experience behind when you go to a park to activate it. This is one of those simple ways to accomplish this goal without having to spend any money or time on it.

The sBitx has quickly become one of my favorite radios to do this kind of operating with, Ashar has really done some out of the box thinking with this radio and it shows. I can simply make all the memory keyer memories I want, I can even make them for FT8 as well as CW and it is easy to edit, has no character limit, and is easy to find in the computer too. I just love how smart this radio is designed. I love the native FT8 mode, the ease of use in CW and how it is even a simple touch screen on top of all that…for 400$. That is hard to beat in my book.

Today also had a new thing happen to me. Look at the log and notice how I worked KC7AC on 15 meters with FT8 then when I moved to 17 meters I worked KL7AC on CW. At first I thought it was a typo in the log but the CW is unmistakable and the FT8 showed that call, which is almost like getting a jinx when talking to a friend or something. HaHa, I just thought it was kind of neat to see that and figured I would mention it at the end. I hope you get out and make some contacts today!

WK4DS

A Frozen activation…

Today (Jan 20, 2024) was a nice day other than the temperature so I figured I would setup a simple POTA site at K-0716 Chickamauga Battlefield on the Tennessee side of the park. This location is called Eagles nest and is a rock quarry probably for road construction in the late 19th century or early 20th century if I had to guess.

To some people 19 degrees doesn’t sound too bad, but for a Georgia boy that is down right cold! I ran the heater as much as possible to “charge up” the cab with as much heat as I possibly could before I started. Haha.

Since I only had about an hour, I figured I would just work 20 meters to have the highest probability of success. As you can see in the photos, this was a fairly simple deployment since it only used the one antenna and a pair of tuned radials. I also ran the coax through the door jamb to keep more heat in the truck. This deployment style netted me an SWR of 1.2:1 which is really good for my uses.

Here is a photo showing the height of the antenna over the ground. I am 6’2” tall. I really think this helps with the take off angle and also allows better impedance matching by allowing the radials to angle down from the mount. At some point I need to do some experimenting with more shorter radials to see how that would work instead. Dave Casler - KE0OG on YouTube has a great video discussing counterpoise wires and it is worth watching if you are interested in this. It is embedded below…

I did a wide angle shot of the operating position today to show how simple it can be if needed. I propped the radio on the storage case and simply used the armrest for my notebook. I operated both CW as well as FT8 today and it worked fine. If you look close, that water bottle in the console is frozen solid. Lol. I did shut down the truck to get rid of some RFI it is making locally as well so heating it up first was a good idea. The band was in great shape today without any fading that I could hear or see. The below photo is of the sBitx V3 software showing the FT8 portion of the band and how it is very busy with activity.

I am still using paper logging while operating in the field even for FT8 so that I don’t lose any of the contacts I make. The sBitx has automatic logging but it does contain some bugs at the time of this writing and will miss one on occasion so to prevent this, I paper log all the contacts during the activation. This is something that I obsess over for some reason, but I do like the peace of mind knowing that I have a hard copy of the activation should something electronic fail.

All in all, I had a really nice time activating on this frigid day and hope that if I get the opportunity, to work you someday as well. Until then, have some fun out there!

A quite soggy activation of sorts

I had a couple of hours today so I went to K-2169 to setup in the truck since it was… a little rainy.

These kinds of conditions are the exact reason I build the “trucktenna” mount for my truck. If I had not done this back last year, I would not have went to a park today and made over 40 contacts. Plain and simple. As you can see I did do some expedient temporary water proofing with some electrical tape, this will do the job for a couple of hours, but make not mistake, this stuff wont keep water out for the long term and should not be a permanent solution. It will get you by at a POTA park though.

I ran out three radials again today as I had plenty of time and wanted the SWR as low as possible since I knew I wanted to attempt FT8 for a while today once I finished my CW section of my activation. I like this location too as it is out of the way of other cars, there is no need to walk behind my truck in the spot so no worries about people getting into the radials, and I can run the radials out as far as I want without and problems at all. I also opted to run the coax through the top of the door where there is no sharp change in direction with the door seal and door jamb, this allows me to keep the window rolled up and rain out of the truck cab better.

There is something about a vintage pickup truck that is just plain cool to me… yeah, this truck is legit 18 years old at this point. Hard to believe that it is that old to be honest, sometimes…

In the above photo I have a picture of a another truck in the parking lot (the black blob on the right side of the photo) that belongs to a couple of frisbee golfers that we out playing a round when I took this photo. That is one dedicate group of people if you ask me…lol. I would not have left the house today with this kind of weather looming over head. I thought it was a funny image with the rain coming down almost sideways and their truck was a little blur across the parking lot from all the water on the windshield.

I shared the above image of the radio to show how the fan is setup and that it even works when the radio sits like this since it is in a armored shell fitted to it. The fan would cycle during the FT8 session a good bit, probably coming on toward the end of each transmission after about 3 minutes of transmitting at 25 watts of output power. It also gets the radio out of the way of the armrest so that I can log easier too. It also puts the screen at an angle that is easier to read as well as manipulate since it is also a touch screen to control the radio and I don’t use the mouse and keyboard in the field, just the touch screen.

In the below photo you can see the radio working WD5BFH for a QSO. This in itself is of no real importance to the story, but I grabbed this image to share a unique trait of the sBitx radio. That is, it will ignore some call signs and will not let me click on them to complete a QSO for any reason. The call W7PK called me several times and you can see many of them in this photo, but I could not accept his call at all. I tired numerous times to select him for a QSO and it would not do it. To test this function, I chose other calls and those worked fine. I don’t know why either is the main problem. I have some homework on this part to figure out, this is not the first time I have ran into this problem on this radio, but it is pretty infrequent. It will just chose someone for some unknown reason and not let them talk to me on this radio using FT8…

You can also see the top of the logbook page also in this photo and this is how I setup the screen when running FT8, it allows me to see the completed and logged QSOs while it is working a new one and I have time to write down the last one and put it into HAMRS for my ADIF file. This is why I like to run FT8 at the beginning (while I am getting my logbook ready in HAMRS and my spot on POTA) and the end of the activations, it allows me time to do housekeeping while I am also able to make some contacts on a different mode as well. I really like that.

I had trouble at the beginning of the activation getting connections on FT8, and that is why I hopped over to CW after only 3 contacts. Sometimes one mode doesn’t work and the other does… it is kind of the luck of the draw. As you can see the CW section showed up in great number.

All in all, it was a good time and I made over 40 contacts today, which is a good day for me. I really like it on days like today as I really couldn’t do much else today, other than work on projects in the machine shop… It was really the perfect POTA outing in my book.

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!