The Nashoba Valley Amateur Radio Club held its annual Homebrew / Show & Tell Night on December 18^th with numerous members displaying their different projects.  It was interesting to see what everybody was working on and here are three projects that really caught my eye.

Mike WU2D & Mark WA1QHQ displayed a number of different projects they had designed and built including a Noise canceller & a Paraset spy radio.  Mike explained his replica of a WWII Paraset spy radio and how it was used.  Originally built by the British it was used for clandestine radio communications in France.  The word Paraset is a combination of “radioset” & “parachute”.  Paraset radios were dropped by parachute behind enemy lines.  Mike & Mark have agreed to come back on March 19^th, 2026, to provide a more detailed presentation on spy radios, their history and how they work.

Phil W1PJE, brought in an old Western Electric automated tube tester from the 1960s.  While tube testers aren’t that unusual, automated ones from that time are.  Phil explained how punch cards were inserted into the instrument to configure the specific electrical parameters for each tube.  The automated tube tester was built into a rugged metal suitcase so it could presumably be tossed in the back of a truck.  Phil also displayed the companion library of old punch cards housed in a smaller rugged metal suitcase.

Tom W1PKX brought in his PKX40 transceiver that he designed and built.  Tom explained many of the features of this high performance 40w transceiver and some of his recent improvements.  I was blown away by some of the CW performance specifications of this transceiver and how they were similar to some top commercial radios.  For more information on this project and others that Tom has made you can look him up on QRZ.com.

Les, N1SV

The Nashoba Valley Amateur Radio Club’s December meeting is Thursday, December 18th, at 7:30 PM at the Pepperell Community Center (in Pepperell). We start gathering at 7 PM to socialize before the meeting starts.

Traditionally, NVARC’s December meeting has been “Homebrew Night” where members bring the things that they have been building all year. Over the last few years, we broadened the focus to include things like software programs you are working on, antenna projects, equipment restoration and repair, and generally anything being worked on that is not commercial off-the-shelf. In 2023 we added a “Boat Anchor Petting Zoo” category where you can show off any of your tube-based equipment.

It’s a great social night where you can experience what other people are doing, ask questions, and rub shoulders with other members and guests. If you are new or not a tinkerer don’t let that stop you from coming and enjoying yourself.

I look forward to seeing you there.

NVARC’s meetings are held at the Pepperell Community Center, 4 Hollis Street, in Pepperell, near the Pepperell rotary.

Thanks, and 73. Please feel free to contact me if you have any questions.

Bruce, K1BG
978-772-2773 or bruce.blain@charter.net

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John KK1X outlines his DX Commander clone antenna. John K1JEB refits a Bencher key so it doesn’t bounce around the shack.

I was both surprised and delighted that my “DX Commander” prototype survived the winds Saturday night during the ARRL Sweepstakes phone contest. A 41 foot (12.5m) mast was held up by three 10″ (25.cm) tent stakes from Walmart! I checked in on it Sunday morning and snugged up the guy ropes. Man, the wind was still howling!

Overall, I think the antenna worked pretty well on all four intended bands. Although the IC-7300 has a typical limited auto-tuner (I use a KX3 in the field – it can tune a vinyl gutter) it tuned well. Better yet, it performed well. I managed over 150 contacts while operating sporadically, perhaps 16 hours in the seat. I only did search-and-pounce, only pouncing on stations I could hear quite clearly at that. I managed to work Bruce K1BG, and he mentioned that he had worked a number of new hams from his Tech classes – YAY!

I used my end-fed-half-wave (EFHW) antenna when 80 meters was open, as the prototype was cut for 10-15-20-40. I’ll likely add an inverted-L element for 80 meters in the next iteration. I didn’t really hold out hopes for a Clean Sweep of all sections, but I did manage 62. It’s clear that neither of my antennas was hitting too far to the west.

I’ll better document the prototype in the December Signal. I’ll have some data including FT8 propagation maps, as well as improvements I’ve already concocted. Well, I call them improvements…

de KK1X

In preparation for a few dozen contacts in the ARRL November Sweepstakes, I wanted a multi-band vertical. I’ve long been a fan of Callum M0MCX who manufactures the real DX Commander. Callum is kind enough to open-source all of his assembly manuals, so it’s easy enough to replicate his antennas.

SWR on 10, 20, and 40 were pretty close to designed sweet spot after a few iterations.

More details in the December Signal. Yeah, I’m a tease…

de KK1X