Sunday, March 21, 2021

Continued 2021 Field Preparation

In my previous post, I mention the radios and supporting gear I'm setting up to take into the field this summer. I was intending to take my DSW-20, but decided I'd rather go with another radio with wider capabilities. I didn't mention it in the previous post because I hadn't decided if I was going to use it or not.

I'm speaking of my HobbyPCB IQ32 5w SDR. It supports CW and Phone on 80-10m, with a lovely color touch screen interface, and built-in PSK31 support with a PS/2 keyboard. The firmware can be easily upgraded through a USB port using a thumb drive (must be under 4gb storage, though). 

Here are the specs, shamelessly borrowed from the website:


  • Frequency Range: 3-30MHz (performance guaranteed on 80/60/40/30/20/17/15/12/10M ham bands)
  • Sensitivity: MDS < -128 dBm on 80M dropping to < -135 on 10M
  • Noise Figure: < 8 dB
  • TX Power: 5W typical, 4W minimum
  • LO Feed-thru: < -50 dBc @ 5W output
  • Spurious and Harmonics: < -50 dBc typical
  • DC Power: 13.8VDC, 2 amp max
  • Size: 172mm x 105mm X 75mm
  • Weight: < 700 grams
  • Display: 3.2" Color LCD Touchscreen
  • Modes: USB, LSB, CW, PSK 31
  • DSP Processor: STM-32, 32 Bit

I was looking at the QRPVer Minion SDR as a potential field radio, given its coverage and its small size, but it has serious issues in CW mode, which plagues a lot of small phone/CW radios -- it isn't full break-in, and the transmit tail is long and terribly formed. This can cause you to miss part of a transmission because your radio hasn't fully switched back into RX mode after sending CW. It also doesn't appear to have been updated since 2019, or at least its website hasn't changed. I've tried sending requests for info to QRPVer, but I have found reviews that say the radio's creator is basically a one-man shop and he doesn't keep up with his emails. Given that he requires 40 days to build and ship a radio, the lack of communication pretty much makes it a non-starter for me. I want to ask a few questions before I order one, and if the creator can't be bothered to answer them, I'm not going to buy a radio from him. So I decided that I was going to revisit the IQ32.

I hadn't used it much because it, too, suffered from difficulties with the CW mode TX/RX switching. But unlike the Minion SDR, the IQ32 is still being updated. The firmware had at least 3 significant revision levels since I'd last updated my radio's code, and the changes made were significant. I think the CW is a lot better than it was, and it seems to recover from the transmit mode far more gracefully than before. It certainly doesn't have that telltale THUMP sound that all too many SDR devices have when switching mode. Semi-break-in is okay, so long as the envelope of the transmission is clean, and doesn't cause you to lose characters from a reply.

The radio has some significant history for me. I first backed the radio's core components on Kickstarter, when it was just the HobbyPCB RS-HFIQ 5w SDR project. I used it for quite a while when it was released, as an adjunct to my computer/ham radio "shack stack" next to my powered recliner, where I spend most of my time. It was a good radio then, using the typical USB/sound card interface, along with HDSDR and Omni-Rig software. But when they announced an upgrade kit to the RS-HFIQ to turn it into a self-contained SDR rig, I jumped at it. I think I have upgrade kit #0002. My order for it was in less than four hours after it was announced available.

Now that the firmware is fairly mature, the radio is a very viable candidate for a field rig. I had hoped to use a uBitX for this, but my uBitX was an early evolution, and I fried some circuitry when I accidentally tried to tune on 160m, a band it'll let you access, but really isn't designed for...and the antenna was my half-size W3EDP end-fed, which definitely was NOT designed to support that band (though the full-sized model I have up as my main wire is). So, until I can find and bodge-wire the PA 12V+ rail, and possibly replace the IRF510 finals, the uBitX is down for the count.

But the IQ32 will do just fine. Technically, I don't really need to take the QCX along if I use the IQ32, but a) I don't believe in having just one radio, and b) the QCX has built-in CW decoding, so I can double-check my copying of incoming code.

I've checked my wire antenna bag, and the ones I like best are in good shape. That'll be a QRPGuys 40/30/20 end-fed with built-in tuner, my Slinktenna, and my homebrewed 40/30/20 link dipole. I still have to check over the Wolf River Coils "TIA" antenna kit I have in the back of my van, and put the short telescoping whip I bought into the kit, to join the standard-length telescoping whip, and the extra-long 209" telescoping whip I already have.

I keep an MFJ-223 1-60 MHz Color Graphic VNA Analyzer in that field kit, mostly for tuning up the Wolf River Coils antenna, but I also have a NanoVNA that I haven't had a lot of experience using as yet. Most of my antennas are pre-tuned or have built-in tuning, but I have an Emtech Z-2 Z-match and an Elecraft T1 tuner. I just have to FIND the's buried someplace in my gear around my chair and isn't immediately visible. That's a task for the beginning of this week. My goal for this week is to get my field gear down to the crash case, the antenna bag, and the long repurposed fishing rod case for the vertical -- a load that I can reasonably carry without using a wheeled hand cart. The cart does make it easier, though, and will likely still do it that way, I just want to be ABLE to carry the requisite gear by hand if I must.

I still plan to make a smaller, field-expedient radio bag, holding only a 40m QCX-mini and a VN-2002 20m Japanese rig, made by Haru JL1VNQ. Those two radios together bulk and weigh less than an original QCX, but each has full 5w CW capability. Those, along with a new Magic Cable, a PD power bank, paddles, headphones, and a purpose-built lightweight 40/20 link dipole, will go in their own bag, something small that can be grabbed and carried easily. It'll probably be the "hoist the feedpoint into a tree" type inverted-V antenna, because that gives the best coverage for the lowest weight and bulk.

Now, I just need to make sure I have the sundry other items that make field operating fun as well as possible. Clipboard, log, phone, maybe my old Chromebook, set up with ham radio apps under GalliumOS Linux. I need to check the ancillary gear I always keep in the van, such as small gas stove, fuel canisters, mug, 3-in-1 coffee packets, utensils, and even some freeze-dried food. I usually don't use them, but they're nice to have in case things are going well and I don't want to have to tear things down in order to get hot coffee or food from the Wawa convenience store a mile up the road. If I can get away with boiling some water to make instant coffee, that's a better solution.

An eventual project will be a field station specifically for digital mode operation. It'll consist of the aforementioned Chromebook, with external USB sound card dongle, cables, and my Midnight Design Solutions "Phaser" 40m 5w dedicated digimode transceiver, magic cable, power banks, and antenna. I can make a pre-tuned dipole for that, given that the frequencies are fairly fixed. I won't bring a tuner or analyzer for that setup.

The weather is beginning to cooperate, with sunny days around 60F starting to happen, so I hope to soon start going to the parks in my area to play some radio!








Saturday, March 13, 2021

Power Delivery and QRP, Revisited

 Power Delivery and QRP, Revisited

Well, Spring is getting awfully close to springing once more. The Vernal Equinox, aka the First Day of Spring, is on March 20th, Daylight Savings Time jumps forward tonight (March 13), and the weather has been a lot warmer lately. It's beginning to look a lot like operating weather at the parks once more.

This means, it's time for me to get my field kit reassembled for the summer. I've got several radios to build, so if I get bored I can start putting some together. Cycle 25 is starting to ratchet upward notch by notch, and the propagation is starting to be worth something again! As per my usual key-shyness issues, I haven't done a lot of CW operating over the winter, but I have practiced a bit and done a lot of listening. Time to finally beat that key shyness and start using the skills I so laboriously built!

I have chosen two radios for the time being, my 40m QCX and my venerable 20m DSW-20. The latter especially will force me to deeply ingrain the Morse numerals in my head, since it has no display of any sort and will announce the frequency the radio is set to with Morse Code. All of the prompts on the radio are in Morse, including the ones to set Speed, Reversing the paddles, and Tune mode. I need to track down my Elecraft T1 tuner, which is around here...somewhere...but for now, I have an antenna analyzer for my vertical, and a pre-tuned link dipole that'll handle both radios perfectly. That reminds me...I need to take the short telescoping whip for the Wolf River Coils Silver Bullet to the van and put it in the antenna bag with the standard whip and the big whip.

I have two portable speakers to use with my radios, since neither one has a built-in speaker. I also have headphones, the kind where each speaker clips over the earlobe. I prefer those, as actual earbuds hurt like hell for me, no matter how I fiddle with them, and regular over-the-ear "cans" get way too hot when operating outdoors and you can't hear anything outside them. With the clip-on headphones, I can even take one side off, so that ear is unobstructed. I can hear if someone tries to talk to me, such as a curious passer-by, or a park ranger wondering what the heck I'm up to (it has happened before).

But the main thing I got squared away, to go with the headline of this post, is what I call my "Magic Power Cable" -- my Power Delivery sink and the PD USB-C power banks that go with it. I'd had some difficulty getting radios to work properly with it last year, so I decided to go through everything and find out why. Well, I did, and boy is my face red!

Turns out that one of the big power banks I was carrying doesn't have a 12v output mode. It has 9v and 15v, but no 12v for some reason. The cable was set up to support a range of voltage, from 9v to 15v, but I don't really want to put 15v through any radio intended for a nominal 12v. I also had the current set way too high, at 2.5A. None of my PD banks actually support 2.5A at 12v. I found this out by reading the tiny, hard-to-make-out writing on each power bank, instead of the advertising copy on the page where I bought them. Let this be a lesson: Do not take the sales page's word for it! Look at the legend on the device itself!

This made me look at the mode settings I had in the PD Buddy Sink in my Magic Cable. I had it set for, as I said before, a voltage range of 9-15v, and a current of 2.5A. I changed this to a strict 12v, but instead of setting current, I set output power to 18W...which determines the current to be 1.5A. All of my PD power banks support this setting. I double-checked with several radios, and it works reliably on each one. The only radio that requires more than 1.5A at 12v would be my KX3, which needs more as it is not a 5W radio. It will do 10W without the amplifier, which requires more current at full power...but 18W out should handle the KX3. The specs call for 1-2A at 12v, and 1.5A is what I have available at 18W out from the power bank. So the new settings will work fine. Sort of moot, given that I really dislike risking the KX3 in the field, but it's nice to know I can use it in the field if I want to on the power banks I have in the case. I also have a 12Ah 12v LiFePO4 battery that I can use for the KX3 if needs be, and the Talentcell 12v power banks that are NOT USB, much less PD, at 12v. I can revert to those if I need to, and I have my larger one in the field crash-case already just in case.

For keys, I have two I've set up for the field. I can set up the NOARC Te-Ne-Ke if I want, and I still might, given that I can mount it on my clipboard with a small nut and bolt to make it very convenient. But this summer, I'm going to try using an inexpensive Supmotor paddle I got on eBay, a cubical thing about an inch on a side with a strong magnetic base and 3d printed fingerpieces and top cover. It's downright tiny, and is very comfortable to use. I'll probably stick a steel plate it came with on the aforementioned clipboard to keep it firmly in place, since both radios have aluminum cases. I may get some additional stick-on steel plates, so I can put one on each radio, but I haven't done that yet.

This summer promises to be a very good operating period. The solar activity level should be very conducive to good DX, and even good local contacts. When it starts looking like 17m is going to pick up, I have a Kits & Parts 5w 17m rig waiting to be built. I also have a QCX-Mini for 40m, and a Japanese VN-2002 5w 20m kit on the bench. If nothing else, I also have another older QCX kit for 30m I haven't built yet, and a 10W 40m SSB rig from CWKits to put together.

I haven't even started to think about digital modes in the field yet. I have my 40m Phaser and its accompanying Chromebook (re-flashed with GalliumOS Linux) for FT8 and JS8 that I can take to the field with no difficulty.

Heck, I even ordered a new package of nanofilter face masks, in case I need them. I usually have a cloth mask in my back pocket just in case, and a member of the Rooster Club sent me a lovely cloth mask with roosters on it I can use. But these are supposedly excellent at filtering out all sorts of stuff and not interfere with breathing, and are touted as very comfortable. We'll see. Nobody should be able to yell at me to get back in my house THIS summer! Seriously, my neighborhood was downright mean about it.

Well, see you on the air!