Why I don’t use the sBitx radio for other modes anymore…

I have an interesting relationship with this radio…

When I first got this radio, I found it had some keying problems on CW but I just adapted to them and used it anyway. These problems are in how the software monitors the CW circuit and keys the radio and such. Turns out that as the radio heats up, the problem tends to get worse causing me to have to slow down the keyer to be able to send accurate code. Even with these tactics, I still send many mistakes towards the end of an activation due to the lag in the keyer.

The reason I currently dont use it for SSB is the audio is terrible and I need to trouble shoot that on the bench to see what is going on there. At first it had a weak microphone element so I made a preamp to correct for this but it still doesn’t seem to work all thatwell. Based on all this, I have not used SSB. (I do plan to revisit the SSB circuit to see if I can get it right)

As I also own several portable Ten Tec and Penntek radios that work wonderfully for SSB and CW, I threw in the towel and just started carrying one of those as well as the sBitx. It doesn’t take long to change out the radios since they are so small and light and I really like the break in on Ten Tec radios (the Penntek has wonderful break in too). Another huge plus is that the filtering on the Ten Tec radios is much better than the sbitx in my opinion. Now to be fair, the sBitx filtering is good, but the Ten Tec radios are just better. The Penntek TR-35 suffers the same problems that the sBitx suffers from. Strong, nearby stations will dull the receiver sensitivity.

What I have found that helps in the scenarios is to simply move. There is nothing an overloaded front end can do to help this problem. I do like the features that are available in CW on the sBitx though. Things like the memories and how easy they are to employ is awesome. Another thing is the waterfall is real nice that runs right alongside the CW decoder which has helped me a couple of times. I dont watch the decoder much, but it is nice to be able to see it match what I copied at times for call signs and such. Another great thing about the sBitx is the touchscreen. Not needing buttons is real nice. The only part of the experience that is honestly lacking in CW is the keying problem. Once someone solves this problem, this will be a game changer for a radio. I am still experimenting with different cooling solutions to keep the machine cooler to see if I can get the keyer to work better.

As you can see, this machine makes for a great FT8 field radio. The lack of a need for an external computer is a huge benefit when it comes to this. I just wished the dev team could sort of the CW keying problem this radio has that makes it less than ideal for this application at this time. One thing I plan to do soon is to set it up and see how running QRP power only helps alleviate the heat problem by not running 20 watts on 15 meters and building up the extra heat. This may solve most of my problems but the radio is designed for more transmitter power so I want to access that power.. Another option is to use a keyboard to send the code as it generates the code internally in software instead of polling the IO architecture to get the keying input. This is fun to me too but a nice key is also fun to use. So till the dev team does come up with a solve for the CW keying problem, I will relegate this radio to keyboard CW and FT8 (and maybe even SSB once I address the audio problem again)… But the main reason I wanted the radio to start with was the built in FT8 function that it has, so in that regard I have a great radio that I love to deploy!

If you are considering getting one of these radios, just be aware that it is far from perfect and it is literally made for experimentation. As long as you keep your expectations in reasonable bounds, this radio can be a lot of fun.

1 POTA, 2 Radios, 3 Modes and 4 Bands!

Today was a fun day…

The location is all too familiar, but I set out to do a sort of special operation today. I wanted to complete a POTA activation using two radios, 3 modes and 4 bands in one sitting. This doesn’t sound like a tall order but since I am operating inside the truck cab, this does involve a little logistics to not just have stuff piled everywhere while I am operating. As you will see in the photos below, I still ran into this problem somewhat, but it was manageable.

I setup at the disc golf parking lot again, but this time there were quite a few people there and some of them actually quizzed me about what I was doing. One gentleman, Jerry as noted in my log, actually chatted for a good bit about how he has been looking to get into ham radio but the Atlanta area is kinda tough on locating local hams for some reason. I gave him a card and told him to email me and I would give him as much info on it as I could find to get him on the right path…

As you can see in the photos, I set up ham sticks and this time I started on 40 meters FT8. I wanted to get the FT8 portion of my “sprint” if sorts out of the way first as the other two modes were going to be on the Ten Tec Scout 555. I had recently activated with it and it was acting up with chirping on CW and reports of RF noise on my audio on SSB. I attributed this to poor connection of the 20 meter band module as it was fine on 15 meters. Armed with this knowledge, before I left out for the park, I took the radio to the shop and use the Deoxit for gold contacts and a tooth brush to clean the contacts on the band modules. I even wetted one module pretty good and used it to “clean the contacts in the radio by plugging and unplgging the module a bunch of times.

This improvised procedure worked as I got good reports and the CW ran flawlessly as you will see later. Deoxit is magical stuff, if you dont have any, it is work your investment to grab a small can of it.

I really enjoy using this radio for my FT8 operating and with the upgraded finals and RF deck, it runs flawlessly now with SWRs in the 2:1 and even slightly higher range without problem. Today saw SWR levels on transmit of about 1.7:1 and it happily skipped right along making several contacts in a row at one point.

After completing 6 QSOs on FT8 I figured it was time to get the Ten Tec Scout 555 out of the case and see what I could scare up on CW.

The 40m Ham stick that I have must have a really high Q as it is very narrow banded. So I have it tuned for the CW portion of the band and the SWR in the SSB area can be quite bad at times. For this reason, I chose not to hunt any SSB contacts on 40 meters today. Once on CW (this was about 1/2 hour later as this is when I talked to Jerry) the band must have been closing or the band noise was getting so bad that I could not hear many stations. I was able to work Alabama and Tennessee before the call signs faded into the noise. That is something you will learn pretty quick about HF radio propagation, if you want to work closer in stations, use the lower bands, but if you want to reach the west coast from Georgia on a ham stick, use the higher bands like 15 and 20 meters. When 10 meters is open I have worked other continents with ease… Don’t discount those higher bands, they are truly magical.

In the above photo I have the CW key and keyer staged but not connected. The mouse is actually driving the FT8 machine and makes working FT8 so much easier to be honest.

In these two photos you can see what you have to work on constantly. The above photo shows the cable that came with my Ten Tec Scout 555 when I bought it. This is a common issue you will find with home shop made cables. These were stripped back way too far and as I used the cable, the conductors started breaking and I was beginning to worry about blowing fuses.

I happen to own a tool that is designed to remove these pins from the connector, so I am able to dismantle this connector properly. I dismantled it, then took it apart and cleaned it up, properly stripped and re-soldered the pins, then put heat shrink tubing on it all to insulated and protect it better. Now I am not so worried about it either shorting and melting the wire or blowing the fuses and shutting down the activation over something as simple as a cable…

Once I finished on 40 meters and had two modes in the bag on one band, I switched over to 15 meters CW to see what was happening there. There was a contest going on so it was a little crowded and I didn’t understand the exchange so I didn’t jump into the contest, but rather setup on a clear spot and calledCQ and worked a couple of stations there, one station of which is DX!!!

At this point. I got a phone call from KG4WBI about a completely unrelated matter, which we discussed and I told him to fire up his HF rig and we would see if ground wave would make the trip to his house from the park so I could get Georgia in the log as well as a 2nd mode on 15 meters! Well, it worked just fine and we had a great QSO on 15 meters SSB before he had to sign off and go run errands. So having confidence that SSB was going to work better I started calling CQ on SSB.

I got literally zero replies to my calls… so I went hunting instead. I found two more ops that could hear me and I was able to bag a couple more QSOs and these were Park to Park contacts to boot!

These three photo show me installing the band module into the Ten Tec Scout 555 transceiver. It really is that simple to change bands on this radio. Now to be fair, this is not as simple as just turning a knob, but it really isn’t that bad.

To remove the module you pull out the bottom of the little lever on the front of the module and it will pop out enough to be able to slip it out, then you grab a different one off of the pile and stick it back in the slot in the radio. Push it to seat it and then your ready to go.

At this point, I switched over to 20 meters and since the PTO (notice it is not a VFO) was still up in the SSB area, I decided to see if I could hunt some contacts with that mode. I landed one contact in SSB on 20 meters and was happy to get them in the log.

After working the one lonely SSB contact on 20 meters, I decided to give CW a try as well… Remember me mentioning a contest? Well, it was here too. It was going strong as well and because of this I was only able to work one contact on CW as well. If nothing else it netted me another band!

My last stop of the day was 17 meters. The 17 meter band is a WARC band and therefore it is off limits to contesting. Now, to be fair, POTA has been called contesting of sorts, but as of right now it is not considered a contest but is more in the spirit of something similar to a rare DX station activating on the same band and developing a huge pileup there. So I proceeded to hunt me an empty spot (18.078mhz) and started calling CQ.

This is when things literally took off! I netted a whole page of contacts in about a 1/2 hour span of time! What a day! 4th band in the books and I was stoked!!! 17 meters must have been where all the POTA ops had went due to the contest and I didn’t get the memo…lol. The Scout worked flawlessly after the cleaning and I cant be happier now with the old girl.

One of the great things about 17 meters is the propagation is really anybodys call. I worked Hungary at one point as well as California, Alaska and Idaho, then there is a ton of east coast stations too, it was everywhere today on 17 meters. Ham radio is so cool…

Before closing today I wanted to mention that Aaron KV9L and I have a youtube channel and we just hit 2000 subscribers (as of this writing)! If you are into ham radio and watching videos about it, then we would love for you to come over! I am currently doing a series of short form videos that are teaching CW one letter per day. There is no limit to the number ofd times you can watch them so I am hoping these become long term training aids for people.

Once I get the letters, numbers and punctuation done, I am going to start doing words next. After words will come sentences so we will see how it goes. Anyway, I just wanted to thank the 2000 people that made us as successful as we are!

73

David -WK4DS

A simple POTA activation

Today saw me use the Ten Tec Scout again to great effect. Below is the case I carry it in showing the full compliment of band modules (I keep one in the radio and today that is the 20 meter module). Under the radio is the power cable in a pocket just for it and next is the spot for the microphone in a more permanent role. You can see the impression from where it sits in the case currently.

These hard cases come from Harbor Freight and make wonderful travel cases for my POTA radios to be quite honest about it. I need to get two more and kit out my Ten Tec Argonaut 5 and my Penntek TR-35 and the set will be complete. The Argonaut has a nice hard case, but it is really large and kinda hard to maneuver with. I thought it would be a great kit for POTA and it does work, but I would really like something different… As an aside, I store the owners manual to each radio behind the lid foam on all of these. That way I have a instruction book should I forget how to do something obscure that I dont use all that often.

I have not dismantled a band module to see what all is inside it but there is a good bit of stuff going on in each one. They are about 3” long and the circuit board goes all the way to the front. So there is plenty of widgets inside them to make the magic happen.

Today, I only used the 15 and 20 meter modules as I was being a little lazy and only put out radials for these two ham sticks. A quick SWR check with the nanoVNA and I was off to the races.

The above shows my CW key and keyer. The key is made by N3ZN and if you have not tried one then I highly recommend them. It works beautifully for me. The keyer is a Picokeyer from Hamgadgets.com and works way better than it should for what it costs. Since Ten Tec radios traditionally dont have memories for the CW keyers, this is the way to have those memories really easily.

The next thing I did that was out of my usual character is to get the hand mic out and work some SSB today as well. It worked OK, but there were times when the audio was odd and I would get little hints to something being wrong but all in all it worked fine.

As per my usual outings, I had the place to myself today with only a couple of cars rolling by during the entirety of my activation. I like it like this though as there is no ignition noise to deal with or inverters making RF hash, just the peace and quiet of the park and my radio chattering in the truck. During this time of day, the sun will beam into my door if I roll down the window beside me so I usually just roll down the other three and the one beside me just a little so the air still moves through the truck taking away the heat from the radio and making it nice and pleasant.

Just look at that parking lot all for me! HaHa! That never gets old! There is just something magical about the peace and quiet of a park like this.

Something I learned today that is different between the Argonaut 5 and the Scout is that I have to use the key jack to make this radio transmit a side tone in CW. I can key the transmitter with the “mic jack cable” that I made for the Argonaut 5 but it wont produce a side tone with the Scout for some reason. So I instead used this port on the back of the radio to get it to work right (see photo below). Another special thing about this radio to me is that it has a Curtis keyer chip in it and you can plug a set of paddles directly into it and it will work as you would expect, but it is in a different port… Go figure. All these options are hot all the time too. Plug a straight key into it and key it to send CW then you could (theoretically) just pick up the microphone and talk to someone on SSB without changing anything else on the radio. It appears that it is in SSB mode all the time and CW is just the side tone being transmitted instead of the audio from the microphone. This does cause one little issue that a user will notice pretty quickly. The zero beat is the display frequency plus or minus (depending on band) the side tone frequency. The filter is simply a bandpass knob that adjust the filter bandwidth and that is it. A very simple radio that just works.

An example of the side tone offset in CW can been seen in the photo above where I am tuned up on 15 meters. It displays 21.0523mhz but the radio is actually operating on 21.053mhz when transmitting. So if you are near the band edges on say 40 meters CW, just keep this in mind so you are not transmitting out of band. The owners manual even mentions this to make sure you stay compliant with FCC regulations.

As you can see from the log above, I started out on 15 meters CW and worked several stations there before moving to 15 meters SSB till the band essentially faded out. At that point I decided to see what would happen if I went down to 20 meters SSB and called CQ… Well the log speaks for itself. I made 26 contacts in 15 minutes! This has to be some sort of world record!!! LOL…for me that is… It was wild how big the pile up was and how quick it happened! The people were super nice and courteous and really helpful so I thank all of you that called me this day and I really appreciate you stopping by to say hello!

73

WK4DS - David

POTA AAR using 3 modes on the sBitx transceiver

Today marks the second deployment of the sBitx and me using it on three different modes.

You see, I spent a good bit of time recently solving the weak audio problem with the SSB mode in this radio. I found the microphone input level is really weak and there was a common solve by installing a more powerful microphone element in the hand mc. I tried this approach and it really didn’t help much for me. l was essentially still yelling at the radio to get it to work. Pictured below is what my radio looked like on the work bench as I worked on the audio level for the microphone input.

I ended up building a pre-amp circuit to boost the audio several dB and this fixed my weak audio problem. I wrote about it in the blog and recently published that post as well if you would like to know more.

Back to the activation, it was a beautiful day and wasn’t really all that hot either. This is a nice departure from the July temperatures I had been dealing with recently.

I setup in my usual place but indexed the truck about 90 degrees so the sun wouldn’t shine directly in my open door. This allowed me to leave it open for the most part. I get so much more aurflow with the door open as opposed to just rolling down the window.

I also ran my 20 meter ham stick on the truck hitch mount I made and just deployed the two radials I tuned for 20 meters. I planned on this activation being kinda short so I didn’t setup for any other band since 20 meters is so active I should easily get my activation locked in on just that band.

I do have some future plans for the antenna mount though. One of thise is to incorporate multiple ham stick mounts (2 specifically) to allow for band hopping without having to get out of the truck. This way if I am setup on a rainy day, I can go ahead and setup two bands at the beginning and then just stay in the truck.

I am beginning to think I want to install a screwdriver antenna again like a Tarheel or something like that and just use that for the quicky ones. I have heard good things about Tarheel antennas and it would make a bunch of my activations so much faster.

I use these CB antenna mounts you get from the truck stops for my base connections. It is an easy way to build an antenna mount from scratch as it has everything you need to attach the antenna to the base.

Something else I like about the sBitx is that even though it is a touch screen design, it can also be mouse operated. This makes using the radio about 100 times easier as some of the touch functions can be fickle. Like picking a station to call on FT8 from the list. It isn’t super hard to do by hand but it is MUCH easier to do with a mouse. Because of this, I have started bringing a USB mouse with me on my activations.

Yet another reason I like this radio… lol. It can also use a USB keyboard as well and you can “type” CW with it if you want but I dont worry with that as I really dont have the room for the keyboard at this time. Maybe at some future point I will add a shelf for those items. Haha.

All in all it was a great activation and I really enjoyed the time at the park as well. It was really cool to be able to use SSB with this radio! That alone made this particular trip unique. I think prior to this that I had made just one SSB contacts total! ONE! Now that mode is going to be showing up in the logs more and more and I can’t wait to share those trips with you one here.

73

WK4DS

Working on the microphone input of my sBitx

This is what a project in progress looks like for me…

I have been hobbled by the low audio in my sBitx since it was purchased back in 2023. This radio is a godsend for FT8 but the SSB microphone level was almost unusable. It was weak and you had to yell at the radio to get it to work at all. I didn’t really want to go into the software and start changing stuff in it, so I decided to bring the level up by adding a pre-amp to the circuit.

So I get out a breadboard and build up a simple audio amplifier circuit on it with a 2N3904 transistor and set about to see what levels I could get with a simple 9VDC battery powering it and feeding the input with the actual microphone I plan to use. I used a couple of potentiometers to adjust the input level and the gain of the circuit so that I could tune it to work with my radio. Below is the circuit I found online (why go to the trouble of designing one from scratch when it has already be invented?) So I built it up and changed 10k resistor and the 100k resistor with the pots I mentioned earlier and it was time to put the scope probe on it and see what I got.

It worked beautifully well. I could drive it to clipping if I wanted but I had PLENTY of gain before that happened. Way more than I needed I would find out later when testing it on the air with my friend on 80 meters. I chose to setup the bench test by simply getting the board out of the radio and powering it without the Raspberry Pi installed, this would power up the audio amplifier circuit without the hassle of it biasing the RF section. I put a scope probe on C119 at the output of the transistor (which you will notice looks very similar to the one I built actually). This circuit powers up when the switch is turned on so you dont need to even have the Pi installed to work with this circuit. For testing I simply connected the output of my amp to the mic jack with jumper wires and then spoke into the microphone while watching the scope. It worked really well to be honest. It worked so well that I looked at the sBitx circuit and figured that full output was 3VDC peak to peak or so as there is a 3.3V zener diode on the input of the IC this circuit is feeding. 3.3V logic protection if what I am figuring and these zeners are clamping the signal to that voltage max for safety.

This was a mistake turns out as it needed me to dial back the input significantly to get good quality audio out of the radio, but I had signal finally! It worked!!!

The yellow trace is what was going into the mic input and the purple trace is what was coming out of the pre amp I built. I was well pleased with this. I then proceeded to move the parts to a perf board and install it into the radio semi permanently to test it.

In the photo below I am pointing at the little “daughter” board I built with my pre-amp circuit on it. I tapped power from the input right at the massive reverse polarity protection diode that I also installed in my radio. The factory diode is really small and if you didn’t consider a small enough fuse in your power cord or worse…no fuse at all, then it will burn open after a short time and will let the reverse voltage wreak havoc on your radio. The reason I know this is that it has happened to others with this radio. This diode, combined with my 10 amp fuse, works like it should. It will blow the fuse every time and not damage the diode. I tested the idea a few times with a few fuses to make sure it would work and it did.

Here you can see how I hard wired the amp into the radio. I lifted the end of the RF choke that was connected to the microphone port and soldered my pre-amp output to the inductor and then my pre-amp input is simply soldered into the through hole the inductor was in. This made for a simple and non-permanent installation should I want to remove my mod at some point. After this, I simply wrapped the board with a little electrical tape and zip tied it in place so it doesn’t wiggle around too much while I test it in the field some. Once I got the pre-amp tied in I realized I was “double biasing” the electrolytic DC blocking capacitor that I was using to couple the pre-amp to the amp in the radio. So I simply removed the SMD resistor RD21 as this resistor is normally used to power the microphone elements and I had my own bias resistor already in the circuit.

Here is what the audio waveform looked like on the radio when transmitting later after I got the radio put back together. Before ( I should have taken a photo…) it was barely visible when you would talk into the microphone. and it was showing power out too!!! Success was had the next day when I made two SSB contacts with it on a POTA activation.

I hope this inspires you to make some improvements to your electronics in some way, this was really fun and rewarding in the end as it enabled a mode on this radio that had been previously disabled by default.

Triple mode activation at US-2169 with 2 radios!

Today was a good day for POTA as I was able to get contacts with 3 different modes in a single activation. Did I mention it rained too?

So today saw the deployment of so many hard shell cases to the park. I went ahead and staged both radios in the truck cab so if it started raining (which it did) I could have access to both radios anyway without having to get outside in the rain. Today saw me use the sBitx V3 as well as the Ten Tec Scout 555 Amateur Transceiver. I like Ten Tec radios when it comes to CW so I wanted the Scout for this mode. I forgot though that I have not outfitted this radio with an external keyer like I did the Argonaut 5. So with the Argonaut still tucked away in the bed of the truck, I just decided to send everything today by hand.

As you can see in the photo below, I ran the hamsticks so I could stay dry inside the truck if it started raining… seems today that was a good call. I only put out the 20 meter radials and the 20 meter ham stick. I thought about hopping on 15 meters for a little bit but the closer the rain clouds got the less I wanted to be handling lightening rods…. I mean, antennas in these conditions.

I checked it with the nanoVNA and the shape of the curve today was such that the CW portion was really well centered and was 1.1:1 on SWR with the chart climbing to 2:1 at the upper band edge. This was completely usable so I didnt bother to tune anything further and just got on the air…and by “tune” I mean “moving the radials around till the SWR plot moves to where I want it in the frequency spectrum”…lol. I can push and pull the SWR null on the VNA by changing the location of the radials in relation to the truck. I am assuming that I am simply tinkering with the capacitance and inductance of the radials as compared to the antenna and it allows me to correct for things…most of the time.

I first worked a few SSB stations before giving up and heading down to the CW portion of the band to see what I could find down there. Seems there was plenty to find as once I setup on frequency and called CQ a couple of times, I had a nice little pileup that lasted for about 15 minutes straight. I was able to work 15 contacts in that time as well. For me, this is “efficient” CW and really fun.

SSB seemed to be thin on stations today and the band was not really happy with this mode, I struggled to get just 5 contacts in the log today on this mode and normally it is much easier to land many more contacts here with the 50 watts that I was able to use. Maybe I bumped my mic gain and had it turned down or something, I just wasn’t getting any takers on SSB for some reason…

The Ten Tec Scout 555 is almost the perfect POTA radio in my book. It needs a nice brick wall IF crystal filter in my opinion, to be fair, as nearby stations would bleed in on the QSO with their energy sometimes. I could tighten up the IF filter width, but the stations would still numb the receiver occasionally and I think a nice 500hz 8 pole crystal filter would be pretty sweet here to solve that… I am looking at a nice audio filter but who knows…I might just try making an IF filter myself at some point. Once I had cleared the pile up I put away the Ten Tec Scout 555 and deployed the HF Signals sBitx V3 (mine is actually a V2 but I have performed the V3 update so going forward I am going to call it a V3)

The only mode I used the sBitx on today was FT8. I wanted to work a few FT8 contacts as well and had synced the time with the internet prior to leaving the house today so I knew it would be good to go. Boy did it deliver on the promise of getting me some FT8 contacts! Once again I stayed on 20 meters and just ran with it as I am also a little bit lazy at times and this was an easy win for me...haha.

I really like the layout and implementation of the sBitx. It is a really fun little radio. Although this radio is missing some stuff inside but that it what makes it so economical too. Things that some people might call “nonnegotiable” like shielding between the RF and computer sections… but I digress. It works for me even with the little rough around the edges stuff here and there.

Now, below is what the sky started looking like by the time I finished playing with CW and decided to get on with FT8. It was scary dark and ominous and then the rain started to fall. I really didn’t mind the rain as I had taped up the coax connection on the antenna and was confident it wouldn’t give me any trouble. What I didn’t factor in was the lightening…

Well, the rain fell and got more intense and more intense as I happily worked FT8 on 20 meters. After a few minutes, the waterfall on the radio exhibited a strange phenomenon. It turned yellow and red (the colors representing the strongest signals)… the whole thing was showing a 599 +30dB signal that covered the entire segment of 20 meters I was watching. This happened to be 6khz of spectrum on the waterfall and at first I thought something was wrong with the radio. Turns out, the radio is fine, this is simply what happens when the atmosphere charges up with static right before a lightening strike! I noticed after a couple of cycles that I would hear thunder off in the distance and then the waterfall would return to normal and slowly start to turn yellow and red again, till I would hear thunder and the cycle would repeat. This was fascinating to say the least, what was more intriguing though was that I continued to make contacts with that much band noise in play. FT8 is a true weak signal mode if I ever saw one.

This is what I am speculating is static charge up in the atmosphere in the photo above of the FT8 waterfall. For those that dont know, this mode does a sort of “talk and listen” thing where your radio sends a message for 15 seconds, the listens for 15 seconds for the other station. So the waterfall wont display anything while I am transmitting since the receiver is turned off. You can see that the cycle right before I sent and how the band was fine and then I send for 15 seconds and then when I go back to listen again, the band is filled with noise.

Let’s shift gears for a minute, the internet is an amazing place. I made this contact at 16:53 UTC and got this email notification just a few minutes later. That is pretty awesome to be honest about it. I remember mailing cards and it might take a month to get one back…

After I finished the activation and waited on the storm to pass, I wanted to do a simple test of the sBitx for a ham that had sent an email asking about the sBitx and how bad were the “birdies” on any given band. I dialed through the 20 meter CW portion up the the FT8 region (14.074mhz) and found what is noted below. In the above photo, you can see the strongest birdie I encountered on this band. That color means it is quite strong in signal level, so if a station was on that frequency, you would not hear it.

I noticed some were strong but they are also very localized. Literally only 200hz wide at the most. I don’t know if this is really band or not, but there were 4 distinct birdies in just the CW portion of the band. If you were worried about this before and didn’t want to have buyers remorse later, then consider me “taking one for the team” as I didn’t have this intel before. I can still recommend this radio for field expedient FT8 and POTA activations as it just works. Sometimes it will ignore a reply to your CQ on FT8 so you have to pay attention to the display on each cycle, but it mostly catches them.

Something I have learned about propagation is that the three modes I am using carry different levels of signal quality to make them effective. SSB (single side band for the newcomer) takes the award for needing the best band conditions of my three regular POTA modes. If the bands wont allow SSB to work or all the stations are “down in the noise” then I move to CW which requires much less propagation to work for me (especially with a good receiver). BUT it pales in comparison to FT8 when it comes to signal to noise ratio. I am blown away that when CW contacts are fading in and out and are in the noise floor that FT8 will be active and I can easily make contacts with it.

This is a day when SSB was “in the mud” but CW was rocking and rolling and had it been in poor shape, I would have went to FT8 for my ten before quitting and going to lunch. Lol

73 - WK4DS

POTA on the 4th of July…hold for second operator.

Today I went for a morning POTA activation at US-2169 and on my way over to the park, I gave KG4WBI (Roger) a call and invited him to join me. He agreed and after a little while of my working some CW on 15 meters, he arrived with a thermos of coffee and an eagerness to make some contacts!

Since I was ahead of him, I went ahead and setup the station complete with a full compliment of radials so I could use any band I wanted (of the 5 I have hamsticks for at this time...) and got it tuned up on 15 meters by making a slight adjustment to one of the radials. As you can see, I chose the usual spot for today’s activation. This was on purpose as I knew the lower area (which is actually where I kind of wanted to go, to be honest) was really busy with holiday traffic. This also meant that there would be more RF noise down there from inverters in the campground and such too.

This upper parking lot doesn’t see near as much traffic so I knew that it would be a much quieter RF environment. Sometimes you just have to choose between comfort (the lower area is in the shade under a bunch of old growth trees) and a quieter location so I could hear better. I chose to hear better since I knew Roger was coming. It wasn’t too bad, but it did get fairly hot towards the end of the activation to be honest about it.

With the antenna strung up and adjusted, I need to choose a radio. The radio turned out to be the Ten Tec Scout 555 because of the power output on SSB(50 watts). I knew we would be using SSB today and wanted to be able to make a bunch of contacts with it since Roger was going to be there as I am secretly addicting him to POTA a little at a time…hehehe. It worked as we operated together while he was there and I made sure he got enough contacts to get his first activation from US-2169. Now to get him an account and to upload his first log so all the hunters will get credit for his contacts too.

The Scout is a really great POTA rig as it has minimal controls on the front to the point that it has what you need and nothing else to be honest about it. It needs a couple more in my opinion and I may just get another one to build into something fun with some more front panel controls on it. But for now, this one works perfectly and I don’t want to risk killing it as I use it as my SSB POTA machine now. Before this one I had only made a handful of SSB contacts at parks and now I have dozens in the time since purchasing this radio. I really love the compact nature of the radio to be honest, I compare it to my Argonaut 5 in usability with more RF output…

Here is another insider tip…You can connect the CW key and the microphone at the same time, this doesn’t seem unusual till you find out there is no mode switch to go between these two modes. You simply start keying CW on the key and it will transmit CW, and then you can key the microphone and transmit SSB in the next moment with no other interaction with the radio other than picking up the microphone. This is really awesome, but it comes with a caveat. The radio is transmitting CW on the SSB mode. This means that you have to adjust the frequency off from the desired frequency by the amount of the side tone, which is about 700 hertz. On top of that, you also have to shift the radio opposite of the sideband direction you are using. So if your on 40 meters, then you have to be 700hz above the desired frequency and if your on 15 meters, then you have to be 700hz below the frequency. This took me a little bit to figure out too as I am used to being able to simply dial the frequency and call it good. So in the photo below, I am actually on 21.042mhz… As the radio warmed up, it shifted in frequency a little. This is why it is important to do two things, let the radio warm up before getting on the air and look at the display from time to time to confirm things have not changed.

What is nice about taking a pile of pelican style cases (none of them are actually pelican cases) is that you can have a ton of extra gear with you so if something goes awry, you have spares. Another thing that happens is you will have access to your favorite hardware like my N3ZN cw key! So I get it out of the case for the Argonaut 5, which is where I store it normally and use it for this activation. The Scout has two key inputs on the back, one if for a straight key and the other is for a paddle. Well, if I use my Picokeyer, then it goes into the straight key input. The paddle input is fed to a Curtis keyer chip and that is built into the radio. The only downside to this keyer, which works beautifully BTW, is that it does’t have memories. I like having memories for POTA as you end up sending some information A LOT and it takes some of the sending burden off of me so I can log and check the radio and such. Turning the page on the log book seems to be a good reason to use memories on the keyer too… lol. If you have the need for a dead simple CW memory keyer, I can recommend the Hamgadgets Picokeyer VERY HIGHLY, it works flawlessly and runs what seems like forever on a single coin cell battery. I am closing in on a year for this one and it is showing no signs of needing a battery yet…

No matter how many radios you take though, if you forget your log book, you will end up logging in your journal…like I did today. I luckily took my journal with me as I like to make notes about all sorts of stuff while I am out and this is another good reason to have it. This is not the first time I have defaulted to this notebook either, it has bailed me out more than once…lol. I did have plenty of pens though so that wasn’t a problem.

Since I got there before Roger, I built the radio out and hopped on 15 meters CW and started calling CW POTA and got some really interesting answers to that call! I worked a station in the UK as well as Germany! The Hamstick is not the worst antenna out there is what I have some to understand. If conditions are not too bad, I can easily work Europe and South America on 15 meters above. Today was no different. I was able to get a couple of DX stations as well as K2E special event station!

Once Roger arrived we switched over to SSB and attempted to make some contacts first on 15 meters, and then 17 meters with literally zero answers on SSB. You see, Roger is still working on his code so he prefers SSB at this time for things like this. So rather than frustrate him with having to listen to code he is struggling with, I opted to set the hook deep and get on SSB.

I think my idea worked, he was really stoked to work so many ops in such a short time. We had a blast and everyone was super nice while we bumbled around handing the mic back and fourth. It was hilarious at times, but we had fun so I am happy. It happened so fast that I had to come up with some really fast shorthand to know which calls we had given “Two Op status” to and which ones I worked by myself. Plus the notebook was also the wrong one and the calls were happening so much faster on SSB, the notebook is a mess.

I can honestly say that taking a second op along to do multi-op POTA is really fun and if you have not done it yet, consider giving it a shot sometime.

The below photo shows you what it looks like to make sure you are hydrated on these hot summer days in Georgia. I have a Nalgene bottle which I am using first since it is not insulated and then a Hydra-flask which is insulated and makes for cool water even when it is burning hot outside of the bottle. On top of that we were drinking coffee while there too, that is just silly if you think about it…

This is the messiest logbook I think I have ever created. Notes just scribbled here and there, edits run roughshod through out the 5 pages, and you can see that it means we had a great 4th of July activation. Thank you to all the hunters that came out to support us on the air and I look forward to recreating something like this again in the near future.

73

David - WK4DS

Scout…ing for contacts POTA style

Today saw me field a “new-to-me” radio, a Ten Tec Scout 555.

If you have never seen one of these radios, you are not alone. This is a radio that was produced for only about 15 years, towards the end of the company’s life before it changed hands around 10 years ago. It is unique in that it doesn’t contain every band but rather only one at a time. These little modules each contain the special bits to make it work on each band they are designed for and the goal back in the day way to just get the bands that you use. Turned out that these radios quickly formed a cult following and they all wanted the “whole set” of bands for them. I have the whole set of bands thanks to KG4WBI rounding up an 80 meter module and presenting it to me as an early birthday present. Once I had the whole set, I felt this iconic antique needed a better way to travel around when in my truck so I went to Harbor Freight and grabbed an Apache 4800 hard shell case for it. The Ten Tec Scout fits perfectly alongside the set of band modules. I even created a pocket under the radio to store the power cord so I have the whole rig in the case. (The 20 meter module is currently installed in the radio in the below photo)

Today saw me back in the “truck-shack” (I think this is what I am going to start calling this in the future) and setting the radio up on the hard shell case in the passenger seat. Today’s setup was not for power access though as my internal power cord it only fused to 10 amps and the Scout draws that much on transmit normally since it is not user adjustable on the front panel…yet.

I have found a website about the Scout that is a literal treasure trove of information about this radio, mainly in the CW mode, but a wealth of information none the less. I found the website by watching Coastal Waves and Wires video here. The website is by NA5N and is linked here for quick access… His mods for the Scout are pretty extensive an he does a great job of documenting the mods as well as explaining the process the radio uses to transmit and receive and he even has these hand drawn graphics that are amazing.

Back to the activation after chasing a rabbit for a minute…

So today I started on 40 meters as I figured I could make a good many contacts there on SSB, problem is that I have tuned my ham sticks for the CW portion of the band and the 40 meter ham stick is not very broad banded so it really wasn’t going to allow this. What did I do then? Well, I got on CW and made a few contacts before moving up to 20 meters where the antenna is broad banded enough to cover the entire amateur band space.

A couple of noteworthy items here. The 36Ah battery weighs almost nothing but packs a ton of energy. I use it from time to time to power my POTA ops but most of the time it is backup power in my shack for use during power outages and emergency nets and such.

The key I am using today is the Gemini and is a great little collapsible travel key. I had one little problem with it right after buying it due to the center post working loose but other than that it has been flawless. Great portable CW key if your wondering.

The antenna setup is as follows, hamstick riser, hamstick in QD socket, then several radials to form a counterpoise. I have taken to running one or two LONG radial now to play with how they interact with the hamstick antennas and so far it has been interesting to say the least.I found that on 40 meters, if the long radials were pulled taught, (I “anchor” them with a simple weight so I dont need tent stakes) that the resonant point would be well under 7.000mhz, but if I pulled just enough slack in them that they laid on the ground all the way except the first 8 feet from the antenna. Imagine gently curving down to the ground about 7’ from the yellow antenna riser then laying on the grass the rest of the way out. This moved the resonant center value up into the CW portion of the 40 meter band.

The point here is that the length and position of your radial field is absoloutly critical to your antenna system as a whole. The more I play with these radials, the more I learn about how they interact with the system and how important it is to measure your antenna prior to starting your activation if you build it on site.

In the photo below you can see how the radials were setup for the 20 meter band.

Remember at the beginning of this story where I mentioned “ominous” clouds? Well, here is a photo of them to show you what I meant. That looks like rain to me, I did get by without getting rained on before finishing, but that looks EXACTLY like the kind of clouds that bring rain to my area of operation.

Some thoughts on the logbook from today. I have gotten very comfortable with paper logging in the field and then transcribing at home. I did it today actually and it was fine…for the most part. But there was a couple of times when I needed a helper to log for me when I was working SSB. SSB happens so much faster than CW does for me that I was struggling to keep up with the log.

If you will notice in my other posts, I will number the QSOs and even write out the time on the FT8 QSOs as they are pretty slow to complete for me. But once I moved to 20 meters today and jumped on the air with more than 17 watts, things got sporty! I literally stopped writing line numbers, abbreviated most of the time stamps and even left out some of the states just to keep up! It was madness! I could not believe how much more your signal gets out with that minimal amount of power increase. It was a blessing and a curse at the same time, I now see why people will computer log in the field and have a helper to log for them so they can keep up. I could have easily worked 100 QSOs without trying hard if I had just stayed longer at the park. The SSB portion was on fire! The CW portion was doing fine too, but there were SO many more ops on SSB on this day…so many more… In the end, I had a great time and even worked my buddy Roger KG4WBI, this has to be my closest 20 meter contact for POTA ever. If I measured it right we were 2.9 miles apart. LOL What a great day to be on the air!

73

WK4DS