I don’t often read comments in ham radio forums and discussion groups.
Recently, however, I was trying to dig up information on a field antenna design and the search results lead me to two articles and discussions on two of the most popular ham radio sites on the internet.
I read through the comments and (you might have guessed) was really disappointed with the number trolls who seemed to thrive in that fertile environment. It blows my mind that discussions like these seem completely unmoderated. I assume it’s a conscious decision since we seem to live in a society that rewards drama and division–I assume this leads to more site traffic and thus more revenue.
It’s a shame. It would be incredibly discouraging to a new ham who is reading the same article and comments looking for ideas. Gives one the impression the hobby is full of (I’ll keep my language clean here) schmucks.
But I digress…
What was perhaps equally discouraging were all of the comments from those who were trying to explain to the authors how the antenna design in their article simply wouldn’t work. Even when the author posted positive results/data from having used the antenna.
While not all of the naysayers were being rude–and sometimes in their roundabout way I’m sure they felt they were being helpful–I can’t help but feel sorry for them.
I had a conversation recently with a ham who upgraded his license for HF privileges primarily to do park activations in the POTA and WWFF programs.
He mentioned that he had a few successful park activations under his belt but was left scratching his head on a couple of occasions when he attempted a Park-To-Park (P2P) contact but could not be heard by the other activator.
He did all of the right things: announced his call sign followed by “Park To Park” twice and was patient while the activator worked a small pile-up.
In one case, he said the other operator had an incredibly strong signal–and having always heard, “if you can hear them, you can work them“–he was really baffled that he couldn’t make contact especially being a desirable P2P. His activations were successful so he knew it wasn’t an equipment issue.
He asked for my input, so I thought I might share a few points here as this is not at all uncommon–please comment if you think of others:
Big power, small antenna
Some activators operate mobile and don’t actually deploy their gear in the field. They simply drive up to a site, turn on their mobile HF rig in the car, and start making contacts with the mobile whip antenna mounted on their vehicle. There’s nothing wrong with this approach in the POTA program (just keep in mind mobile activations are not allowed in SOTA). Mobile activators can rack up numerous park activations in one day often regardless of weather or any site restrictions.
Mobile vertical antennas like Screwdrivers, Hamsticks and whips are quite impressive and, many activators swear by them. Not only do they work well in mobile situations, but they can also be quickly set up on a tripod in the field and many models can take a full 100+ watts of power.
If an activator is pumping 50-100 watts into a small, resonant mobile antenna, their signal is getting out there. But since their antenna might not actually have a lot of gain or efficiency on 40 or 60 meters, it can’t compete–in terms of reception–with a large aperture wire antenna.
In this scenario, the activator might be logging a load of stations, but they may not be able to hear your signal if it’s weaker than the others in the pile-up.
QRM on the other end
This is a big one, actually, and affects both park and, especially, summit activations.
Sometimes the other activator’s site is plagued with QRM (radio interference) emanating from power lines, nearby buildings, transmission equipment, and other electronic sources.
That QRM will not typically affect their transmitted signal, but it will have a dramatic impact on what they can receive andhear.
For example, I recently attempted to activate a game land I’d never been to before. On Google Maps satellite view, the site looked pretty darn remote and there were no buildings in sight. When I arrived on site, I set up my station, spotted myself, and started calling CQ POTA.
When I turned up the volume on the radio, it hit me that my noise level was a solid S8-S9! Turns out, there was a nearby power line that was spewing broadband noise across the entire HF spectrum. It was pretty much inescapable–there were no unaffected HF bands.
Had I really wanted to continue with that activation (I did not) I would have only been able to work stations with signals that were above my high noise floor. Perhaps one in five contacts at best. My chasers would have all been been left scratching their heads.
QRM isn’t always S8, but even an S5 or S6 noise level might wipe out 40-50% of the signals the activator can hear.
While hitting the field is usually the best way to escape QRM, there are spots that are as noisy an an urban neighborhood.
This is a big one; especially with the unsettled conditions we’ve had over the past couple of years. QSB, or signal fading, can be a proper obstacle in completing a contact.
If you’ve been watching my activation videos, you’ve no doubt seen chasers that call me with a 599 signal and when I respond to them, I hear nothing but silence. In those situations, I’ll repeat my reply with their callsign and signal report a few times in a row. I do this because QSB is a bit like having a three year old playing with your volume control while you’re on the air.
Seriously, imagine that three year old turning up the volume, then turning it back down, then turning it up again, and so on. It essentially has the same effect. Sometimes QSB is shallow and slow, other times it’s deep and fast–or it can be any variation in between (including deep and slow which is the worst).
In those situations as an activator, I reply a few times in a row with hopes to catch the QSB on the upswing so I can have a window of contact with the other station. When I do make contact, I try to keep the contact as short as possible so there’s hope for a complete exchange.
As a hunter, you have less control because your only hope is that QSB will be at the peak of signal strength when you call the activator.
If you’ve been doing park and summit activations for very long, you’ve no doubt experienced some “environmental distractions” during an activation.
I’ve been at parks before when the grounds crew were blowing leaves, mowing, and using other lawn equipment. It can be proper audio QRM especially if you don’t have an option to wear headphones to isolate those noises.
Sometimes the wind can cause a lot of extra noise. I’ve also been in shelters where the rain hitting the tin roof (while somewhat soothing) adds a lot of extra noise.
I’ve also been on summits and in parks where other hikers and passersby start asking questions while I’m in the middle of handling CW contacts.
They don’t understand that you’re actually in the middle of an exchange and need your attention focused. 🙂 For so many of them, it’s the first time they’ve ever seen/heard someone operating Morse Code and they’ve loads of questions. I hate to pass up an opportunity to promote amateur radio, so I’ll often pause the activation to talk with them.
If you know your radio equipment is functioning as it should but you can’t seem to grab the attention of an activator, keep in mind that it’s likely them, not you.
They’re not ignoring you, they simply can’t hear you.
The best practice for eventually making contact is to be patient and persistent. If you’re an activator trying to work another activator for a P2P or S2S (Summit To Summit) contact, keep sending P2P or S2S with your call. Often, other hunters will hear you and point out to the activator during their own exchange that there’s a weak P2P or S2S operator calling. More often than not, that’s your ticket to busting through!
Did I miss something? Please comment and share your thoughts and tips!
Each time I head to a park or summit, I have a goal in mind.
With summits, it’s getting to the summit and activating it because, sometimes, that can be a challenge in and of itself. I’m not exactly Sir Edmund Hillary, so I’m happy when I make it to the top of any summit!
Parks, however, offer me the chance to experiment with transceiver/antenna combos, test gear, and explore hikes. Parks tend to be more accessible and spacious than summits and even have shelter options if weather is questionable.
I don’t even attempt afternoon summit activations if they require a decent hike and there’s a good chance of pop-up thunder storms.
On Monday, June 7, 2021, it was hot and incredibly humid in the Piedmont of North Carolina. That early afternoon, little patches of showers were passing through the region delivering brief, isolated downpours.
The weather forecast also predicted a high likelihood of thunderstorms that afternoon. (Turns out, they were correct.)
Those were not conditions for a SOTA activation, rather, I decided to pick out a park I knew could offer up some shelter options. Lake Norman was an obvious choice–there’s a very nice covered area at their visitor’s center and also two large picnic shelters at the other side of the park. Lake Norman it was!
I drove to Lake Norman State Park with one goal in mind: deplete the Xiegu X5105 internal battery. I had assumed the battery would only power the X5105 for perhaps two activations on one charge.
Now three full weeks later, I decided I would deplete the battery at Lake Norman because that afternoon I had a decent amount of time to play radio in the field. In my head, I was prepared to squeeze perhaps 30-45 minutes more air time out of that one May 16 battery charge.
Lake Norman (K-2740)
I arrived at Lake Norman State Park and scouted out a site. Fortunately–it being a Monday in the early afternoon–it wasn’t busy and all three shelters were available.
I chose to set up at a shelter at the far end of the main picnic area.
The humidity was so thick that day, I was sweating just walking around the site. I noticed in my activation video (see below), I was breathing as hard as I would hiking to a summit even though I was just tooling around the picnic shelter.
I had no doubt in my mind that if a thunderstorm developed, it would be a doozie! (I was right about that, too–keep reading.)
On The Air
I paired the Xiegu X5105 with my Chameleon MPAS 2.0 mainly because I wanted to see how easily the X5105 ATU could match this multi-band vertical. Turns out? Quite easily.
I expected the X5105’s battery to deplete to the point that I would need to use an external power source to complete the activation, so I connected my QRP Ranger battery pack, but didn’t turn it on. I knew that when the radio died, I could flip the QRP Ranger’s power switch and perhaps only lose a few seconds of air time.
I hopped on the air and started calling CQ. I planned to operate the X5105 until the internal battery died, then (if needed) continue operating with the QRP Ranger until I logged my 10 contacts for a valid activation. Post activation, I planned to hike one of the Lake Norman loop trails.
Normally, I would mention the number of contacts I made perhaps noting the bands that were most productive. Instead, if you’d like to experience this activation with me, you might consider watching the activation video.
Please note that this is the longest video I’ve ever published, so don’t feel any pressure to watch it in its entiretity:
Let’s just say that the X5105 sold me.
The activation was incredibly fun and I logged 20 stations (18 CW and 2 phone) from Alaska to Spain with my 5 watts and the MPAS 2.0 vertical. Propagation conditions were only “meh” but since I had the time to play radio longer, I was able to take advantages of little openings as they happened.
The X5105 won.
I simply gave up on trying to deplete the internal battery because I was running out of time to fit the activation and a much needed hike that afternoon before thunderstorms moved in.
I operated over 90 minutes with constant CQ calls and the battery never made it below 10.2 volts.
A most welcome surprise.
No mic, no problem!
During the activation, I remembered that I had been asked by readers and viewers to include more SSB work.
Problem was, I left my X5105 mic at the QTH (nearly 2 hours away by car).
I remembered though that, like the Elecraft KX2, the X5105 has a built-in microphone.
I decided to give that mic a trial by fire and, by golly, it worked!
Not only did it work, but it worked well.
The X5105? A keeper.
It was at Lake Norman that day, I decided the X5105 was a keeper.
That evening, I reached out to Radioddity–who lent this X5105 to me–and offered to pay full retail price for it either in cash or via ad credit
Since Radioddity is a sponsor on my other radio site–the SWLing Post–we decided that, since their ad was coming up for renewal soon, I would simply extend their ad time an equivalent amount of months as the full value of the X5105 ($550 US). This saved them from having to cut a check in two months. Worked for both of us.
I have much, much more to say about the X5105 and will do so in an upcoming review.
In short, though? It’s not a perfect radio by any means, but I feel like it really hits a sweet spot for the QRP field operator.
I enjoy putting it on the air and it’s an incredibly capable little transceiver.
I’m very pleased to now put it in rotation with my other field radios. Look for it in future reports!
Here’s the QSO Map for this activation (click to enlarge):
Hike and dodgy weather
After packing up my gear, I walked over to a nearby trailhead and checked out the trail map. I was prepared to take a very long hike that afternoon despite the heat and humidity, but I also knew conditions were ripe for a thunderstorm.
I decided to take what appeared to be a fairly short loop trail along the lake. Looking at the map, I assumed the trail might be 1 mile or so long.
The hike is well-worn and well-marked, so there’s no getting lost here. That’s one of the reasons I didn’t bother looking at my GPS map or even consulting the trailhead map in detail.
Instead, I simply started hiking the Lake Shore Trail loop. It was gorgeous. Here are a few photos (click to enlarge):
The skies started getting dark, though, and I heard a little distant thunder.
I decided it might make sense to consult my phone for the weather map.
A line of thunderstorms had developed and they were sweeping toward me. Time to pick up the pace of hiking!
It was at this point I realized I had underestimated the length of this loop trail. Part of me was quite pleased that it was longer than I anticipated, but the part of me that didn’t want to be caught out in a t-storm wanted to get back to the car ASAP.
I checked another weather map a few minutes later.
I decided that jogging the rest of the trail made sense!
Turns out the 1 mile loop was something closer to 3 miles when I included the walk back to the car.
I did make it back to the car in time, though, right before the heavens opened.
It’s no exaggeration to say that I was sincerely concerned about the possibility of tornadoes in that storm front.
The skies were dark enough that streetlights turned on and the rain was incredibly heavy with strong wind gusts. I saw flash flooding and driving conditions were nearly impossible. I parked next to a brick building in the town of Catawba and waited for the strongest part of the storm to pass. I was also very grateful I wasn’t still on the trail by the lake!
Of course, the storm passed and I expected conditions to be a little drier behind that front, but I was wrong. I think the humidity level increased to 150%. Ha ha! No worries, though, as I was on my way to air conditioned space!
Thanks so much for reading this field report and stay safe out there!
It seems folks are now finding out about the new Xiegu X6100 HF & 6 meter portable transceiver.
There have been a few rumors about it, so I thought I’d share some of the few details that have been confirmed.
What is the X6100?
If the Xiegu X5105 and Xiegu GSOC had a baby, it would look like the X6100.
The X6100 is a completely self-contained SDR QRP transceiver much like the X5105. The X6100 sports a 4″ high-resolution color capacitive touch screen and is built on on a quad-core processor, 4G ROM, and 512MB RAM. I assume this will run on a similar Linux version/distro as the GSOC.
The X6100 will include an internal automatic antenna tuner (ATU) and a 3500 mAh internal rechargeable Lithium Ion battery pack.
Power output will be 5 watts when using the internal battery pack and 10 watts when connected to an external power source.
Modes: USB/LSB (J3E), CW (A1A), FM (F3E), RTTY (F1B), AM (A3E)
Pricing and availability have not been determined at time of posting. I will post an update when that information can be confirmed.
I can only assume bringing this new radio to fruition will take time. Most radio manufacturers are struggling to keep up inventory levels as we work our way out of the C-19 pandemic supply chain issues. Parts availability has become a real issue.
On a gray Friday afternoon last spring, Steve Galchutt sat high atop Chief Mountain, an 11,700-foot peak along Colorado’s Front Range. An epic panorama of pristine alpine landscape stretched in almost every direction, with Pikes Peak standing off to the south and Mount Evan towering just to the west.
It was an arresting view, and the perfect backdrop for a summit selfie. But instead of reaching for his smartphone, Galchutt was absorbed by another device: a portable transceiver. Sitting on a small patch of rock and snow, his head bent down and cocked to one side, he listened as it sent out a steady stream of staticky beeps: dah-dah-di-dah dah di-di-di-dit. “This is Scotty in Philadelphia,” Galchutt said, translating the Morse code. Then, tapping at two silver paddles attached to the side of the radio, he sent his own message, first with some details about his location, then his call sign, WG0AT.
At this point, a prying hiker could have been forgiven for wondering what, exactly, Galchutt was doing. But his answer—an enthusiastic “amateur radio, of course!”—would likely only have further compounded their confusion. After all, the popular image of an amateur-radio enthusiast is an aging, armchair-bound recluse, not some crampon-clad adventurer. And their natural habitat is usually a basement, or “ham shack,” not a windswept peak in the middle of the Rockies.
Galchutt fits part of this stereotype—he’s 75—but the similarities end there. An avid hiker and camper, his preferred shack is atop a mountain, and the higher the summit, the better.
Another rapid-fire burst of dits and dahs sprung from the radio. “Wow!” Galchutt said, “Spain!”
Nearby sat Brad Bylund (call sign WA6MM) and Bob and Joyce Witte (K0NR and K0JJW, respectively). Together, the four are part of a group called Summits on the Air (SOTA), an international, radio version of high pointing. […]
While I tend to use small, field-portable transceivers on many of my Parks On The Air (POTA) activations, I also love using tabletop transceivers when I have a picnic table available or decide to use my portable table. Tabletop radios often provide more power output when needed and better audio from their built-in speakers.
Although I have an Icom IC-756 Pro transceiver, and an Elecraft KXPA100 amplifier that I can pair with my KX2 and KX3 (or any QRP transceiver for that matter), my favorite tabletop fiel;d radio at present is the Mission RGO One 50 watt transceiver.
In short: it’s a brilliant, simple, tabletop transceiver that’s very happy in the field and a pleasure to operate. My RGO One has the optional built-in antenna tuner (ATU). The rig designer is allowing me to keep this unit on extended loan as I help him evaluate and test updates and upgrades.
While I’ve used the RGO One on numerous POTA activations, I don’t believe I’ve ever made a video of it in use, so I decided to change that last week with another one of my real-time, real-life, unedited (lengthy!) videos of this activation (see video below).
Lake Norman State Park (K-2740)
As I’ve mentioned before, I love activating Lake Norman State Park because it has numerous spots for setting up my gear. While I actually prefer activations that require a bit of hiking, it’s nice from time-to-time to activate a state park that has so many widely-spaced picnic tables under tall trees. That, and my right ankle is still healing after I twisted it in December, so I’m avoiding any proper trail hiking until it is better.
I made this activation of K-2740 on January 4, 2021.
Since I have Internet access at Lake Norman, I can check out the POTA spots page on my phone or tablet and self-spot as well as see spots of other activators.
When I have Internet coverage like this–and I’m not pressed for time–I try to work as many Park-To-Park contacts as I can before I start calling CQ POTA myself.
As I mention in the video, one of my 2021 goals is to obtain a valid activation of each park with only five watts or less. This means that each time I start an activation, at least my first ten stations logged will be with a max of five watts of power. I would actually make the goal for all of my 2021 activations to be 100% QRP, but I evaluate gear regularly and part of that process is to push wattage limits so it’s simply not realistic.
This isn’t actually a crazy goal because a number of my transceivers max out at five watts or less, and I know it won’t be an impediment as I activate parks in CW.
In SSB, though? It makes it a bit more challenging, but certainly not impossible and I’m always up for a challenge!
So I started this activation by trying to work a few Park-To-Park contacts but first cranked the RGO One power down to five watts. Trying to be heard over other hunters in SSB was difficult, but CW was much easier.
After working a few P2P stations, I started calling CQ on the 40 meter band in SSB. I worked about four stations, then switched to CW and worked seven more on 40 meters.
Since I’d snagged my ten contacts for a valid activation, I moved up to 20 meters phone (SSB), cranked up the power to over 40 watts, and started calling CQ POTA and racked up an additional 11 contacts for a total of 26 contacts logged at this activation.
Here’s my QSOmap:
Note that I left the callsign labels off the map this time to make it a little easier to see the geo location of the stations I worked.
Andy’s article caused me (yes, I blame him) to wax nostalgic about the popular FT-817 transceiver. You see, I owned one of the first production models of the FT-817 in 2001 when I lived in the UK.
At the time, there was nothing like it on the market: a very portable and efficient HF, VHF, UHF, multi-mode general coverage QRP transceiver…all for $670 US.
In 2001? Yeah, Yaesu knocked it out of the ballpark!
In fact, they knocked it out of the ballpark so hard, the radio is still in production two decades later and in demand under the model FT-818.
I sold my FT-817 in 2008 to raise funds for the purchase of an Elecraft KX1, if memory serves. My reasoning? The one thing I disliked about my FT-817 was its tiny front-facing display. When combined with the embedded menus and lack of controls, it could get frustrating at home and in the field.
When I told Andy about my ‘817ND purchase, he asked if I’d like to help him test the FT-817 Buddy board versions. How could I refuse?
Andy sent me a prototype of his Version 2 Buddy board which arrived in late November. I had to source out a few bits (an Arduino board, Nokia display, and multi-conductor CAT cable). Andy kindly pre-populated all of the SMD components so I only needed to solder the Arduino board and configure/solder the cable. I did take a lot of care preparing and soldering the cable, making sure there was no unintentional short between the voltage and ground conductors.
Overall, I found the construction and programming pretty straight-forward. It helped that Andy did a remote session with me during the programming process (thanks, OM!). Andy is doing an amazing job with the documentation.
I do love how the board makes it easier to read the frequency and have direct access to important functions without digging through embedded menus. While there’s nothing stopping you from changing the program to suit you, Andy’s done a brilliant job with this since he’s an experienced FT-817 user.
The Nokia display is very well backlit, high contrast, and easy very to read.
“Resistance is futile”
I mentioned on Twitter that, with the backlight on, the FT-817 Buddy makes my ‘817ND look like it was recently assimilated by The Borg.
Don’t tell any Star Trek captains, but I’m good with that.
Andy has a rev3 board in the works and it sports something that will be a game-changer for me in the field: K1EL’s keyer chip!
This weekend, both of my middle school-aged daughters passed their amateur radio exams with colors flying. Volunteers with the WCARS VEC were kind enough to meet us at a local park to conduct the test in a covered picnic area.
At the test site I was more nervous than my girls were, but I really had nothing to fear. Both were hitting a 95% pass rate on practice exams in advance.
Even though the girls have obviously learned a bit about radio through osmosis in this household, they did all of the exam prep on their own. Funny story: I remember allowing them both to send CW to my buddies K8RAT and WD8RIF on my lap when they were maybe 2 years old? Of course, they had no idea what they were sending, but they loved playing with the “clicky thing” (my paddles). I think WD8RIF actually copied their code to paper. 🙂
I purchased both of them an FT-60R handheld radio from Universal Radio. I think these HTs should serve them well for many years to come!
I know one of my daughters is already chomping at the bit to pass her General now.
Anyway, thanks for letting me brag a bit here. I’m certainly a proud papa!
Many thanks to SWLing Post contributor, Frank (ON6UU), who shares the following guest post which expands upon his previous DB4020 article:
The EA3GCY DB4020 transceiver now has CW mode
by Frank Lagaet (ON6UU)
After telling you all about the DB4020 SSB build I’m here with the CW part of the kit, let’s say this is part 2. At a certain moment Javier let me know the CW interface kit was ready for shipment and some week later it was delivered to my QTH.
Again, a well packed kit arrived in a brown envelope, components and boards well packed in bubblewrap. I found even a board I did not expect which can hold a push button, a switch and the connector for your morse key. Javier thinks of everything it seems!
Unpacking the bubblewrap gave me this result, all components in 2 bags. In the bigger bag another 2 bags with 2 printboards, one for the CW interface, one for the CW filter. Great !! Checking the material bill resulted in all components there, another thumbs up.
I started, of course, immediately building it because I wanted CW in the transceiver as soon as possible. I don’t do much in SSB mode anymore and I already started missing CW on the DB4020, so I started my KX3 to listen to while I was populating the boards. I never thought CW was going to have this impact on me! …. ..
I started building the CW interface, again starting with all small items. I soon saw that the 2 relays which need to be soldered in were ideal to protect all components when the board is upside down, so I soldered them in very quickly. I then soldered in all other components ending with the elco’s.
Next phase was the CW filter. This board is small and came together in a blink of an eye, no problems there, the long legs of the 3 and 4 pin headers went in last.
The following day, I made all wire connections and soldered a 13pin connector, leaving one pin out since I want to have the option to choose the width of the CW signal I’m listening to. By cutting the FL CW + pin and adding an additional switch, I have now 500Hz or 2400Hz. Great option, for very little effort and simple. Another thumbs up here.
Now it was simply a matter of inserting the sub boards in the main board and all should be working. And it did! Hurray! The 500Hz filter works perfectly, filtering away all above or below stations nearby my operating frequency.
This is the result of the soldering work, 2 small boards which need to be inserted in the main board:
The CW interface still needs the 13pin header of which I cut one pin and mounted a switch to have the 2400Hz width.
The IC you see in the middle of the CW interface is the KB2 keyer which gives you several functions like 4 memories and beacon mode. The 4 potmeters are used to set the level on 40 and 20 meters, to set the delay between TX and RX switchover and to set side tone monitor level. The keyer also provides functions as keyer mode A or B, straight key function and can be set for speeds between 1 and 50WPM. WPM speed can be set in 2 different ways. Handy!
Here a picture of the CW filter inserted on the main DB4020 board.
The CW interface is inserted at the side of the main board, notice the 2 wires which go to the switch to allow switch-over between 500 and 2400Hz.
(Wiring still needs to be cleaned up in this picture.)
Finally, the result: a good working multimode QRP transceiver with 2 bands. It should be possible to make close to medium range with it as well as DX, even with QRP power.
And while I was building I also made a new key for this radio, it is made out of a relay and cost nearly nothing, looks good doesn’t it ? hihi.
The key, when in practiced hands (fingers hi), can do 50 WPM without a problem. My friend HA3HK does without blinking an eye at 40WPM with this kind of key and tells me that he can go faster if needed. Me? I’m going it a bit slower.
As this radio is only using little power (0.4A in RX, 1 to 2A in TX depending the power you set it) I thought, let’s make a battery pack for the radio.
The first plan was installing it in the box. I did not do that because the batterypack is also powerful enough to feed my KX2 and other QRP transceivers. Since I can use it with all of them, a loose battery works out better for me.
I started with an old laptop which had a broken screen and some other malfunctions, but still had a good battery, although I needed the battery connector of course. A piece of wood to mount the connector on was my next goal. And since I still have another laptop using the same batteries, I can charge the battery without problems. Simple, but good and it weighs much less than a gel cell battery.
The battery provides me with 12.5V and some 5Ah. Enough to last for hours on RX and for sure good enough to activate 2 SOTA sites in one day. It doesn’t look great but works great– that is what matters and to test it was more then good. Next will be getting the battery pack in a nice box. Better to re-use stuff than throwing it away I’m thinking.
I need to do something about the cover of the OLED display, there is still some work there to make it look nicer.
Some video can be seen on YouTube :
Finallym I’d like to thank you all for reading my articles about the DB4020. I had big fun soldering, tinkering with the box, making the key, and batteryholder/batterypack. My Hungarian friend HA3HK told me it looks a bit like a spy radio. …. ..
I also include one more time the link where you’ll find this kit :
Thank you so much, Frank. No doubt, you had a lot of fun putting this excellent little kit together.
Implementing a filter switch was a fantastic idea and, obviously, not terribly difficult to do.
Based on the videos, the DB4020 has a low noise floor and very good receiver characteristics. I’m impressed that the CW portion of the radios has so many features as well, such as a memory keyer and beacon mode.
I also love how you reused that 5Ah laptop battery! I think that could almost give you a full day of SOTA activations at those consumption levels!
Thanks again for sharing this with us, Frank! We look forward to your future articles!
At first glance, you’ll see a similarity between the ALT-512 and the LnR Precision LD-11/Aerial-51 SKY-SDR. The LD-11 and SKY-SDR, are very similar, save the LD-11 is marketed to North America (via LnR) and the SKY-SDR to Europe. The SKY-SDR had several iterative upgrades, most importantly the dual-threaded software used in the firmware, which cut CPU latency in half. Both the LD-11, SKY-SDR and now the ALT-512 are made in Europe.