For my linked dipole, I came up with using high-shrink (I use 4:1) marine (lined with heat-activated glue) heat shrink tubing and dacron line for making neat links that wind nicely and avoid putting stress on the wire.
Today I realized that I could use the same technique to put loops at the ends of my end-fed antenna and counterpoise wires. I can use these to attach to push-up masts or throw lines or anything else. For a counterpoise line, I can even slip it over a convenient twig to help hold a counterpoise out and preferably elevated.
I cut pieces of thin heat shrink tubing about 2cm long, and loops of dacron maybe 10cm long (I didn't measure, I just eyeballed).
I doubled the line and put it through the heat shrink, with the loop barely visible.
I laid the wire next to the ends of the line, and slid the heat shrink down, burying the end of the wire, which has high voltage on it when it is used as an antenna, just a few mm inside the end of the heat shrink, to insulate it.
I applied heat to shrink it, giving me a fixed loop.
I did this for my 40m EFHW, 35.5' EFRW, 33' long counterpoise, and 13' counterpoise wires.
The pictures here are of my 35.5' DX-WIRE UL dacron-core EFRW line.
I'll find out whether these short pieces of heat shrink are strong enough in practice, but based on what it took to disassemble some of the links on my prototype for my linked dipole, I think it will be more than sufficient.
#HamRadio
The case for my 28g QRP dual-ported (9:1 and 49:1) unun cracked from tightening one of the terminal screws too tight, and from having printed the box with too few perimeters, so it wasn't really strong enough. I had designed it so that the coax was integrated into the case, so I had to cut the case apart to remove the still-functional electrical components for re-use.
At least this gave me a chance to confirm that I hadn't blown up the ferrite from overheating it!
I redesigned the case to no longer run the coax through a small hole. It turns out that the cut-out also makes it easier to assemble.
I printed the box with an extra perimeter to make it stronger, made the nut recesses shallower, and added a cable tie for strain relief, which makes the whole thing (including the coax and BNC connector) weigh 29g, 1g more than the previous iteration. Still just about 1oz in imperial measurements. Not the heaviest thing in my radio bag!
Updated design files and README now available in the repository. I still haven't added assembly pictures, but I think it would be possible to assemble just from what I've written. I hope.
https://gitlab.com/mcdanlj/QRPUnun
The case for my 28g QRP dual-ported (9:1 and 49:1) unun cracked from tightening one of the terminal screws too tight, and from having printed the box with too few perimeters, so it wasn't really strong enough. I had designed it so that the coax was integrated into the case, so I had to cut the case apart to remove the still-functional electrical components for re-use.
At least this gave me a chance to confirm that I hadn't blown up the ferrite from overheating it!
I've spent the past year learning Morse code, and it's ended up being a great deal of fun. I've had a lot of questions. I've tried to share what I've learned with others as I've gone along.
To celebrate the end of the year, I wrote a combination of information, story, and advice. How to get started, mobile apps and websites, books, getting on the air, learning to send, POTA, SST, keys and keyers. I'm not fluent or expert yet, but that means that I still remember what's hard!
https://musings.danlj.org/2025/12/26/one-year-of-morse-code
#HamRadio #AmateurRadio #MorseCode
Please feel free to comment with suggestions for additions. I've already added several improvements since publishing this last night, including multiple suggestions sent in DMs here. DMs or public comments are both welcome, whatever is most comfortable for you!
In particular, I have recently added the previously-missing descrpition of Ultimatic mode as well as a warning not to try sending with Bluetooth audio due to delay.
I've spent the past year learning Morse code, and it's ended up being a great deal of fun. I've had a lot of questions. I've tried to share what I've learned with others as I've gone along.
To celebrate the end of the year, I wrote a combination of information, story, and advice. How to get started, mobile apps and websites, books, getting on the air, learning to send, POTA, SST, keys and keyers. I'm not fluent or expert yet, but that means that I still remember what's hard!
https://musings.danlj.org/2025/12/26/one-year-of-morse-code
#HamRadio #AmateurRadio #MorseCode
Looks like he made it all the way there. 12h 8m flight.
Here's the story. It's amazing! Two pilots in a Discus Duo. Starting at 3AM local time and flying with night-vision goggles!
https://www.weglide.org/flight/978820
Airplane with incapacitated pilot lands safely thanks to emergency autoland system:
https://avbrief.com/autoland-saves-king-air-everyone-reported-safe/?utm_source=newsletter-88&utm_medium=mastodon
I haven't listened to the attached LiveATC recording, but there is one if you are curious how an air traffic controller would mix emergency automated traffic with normal human-piloted traffic.
This is an amazing soaring flight!
https://www.flightaware.com/live/flight/N189DT/history/20251219/1200Z/KMEV/KGCK
#aviation #soaring
Looks like he made it all the way there. 12h 8m flight.
This is an amazing soaring flight!
https://www.flightaware.com/live/flight/N189DT/history/20251219/1200Z/KMEV/KGCK
#aviation #soaring
For my #HamRadio tunable elevated radial project, I want to isolate them from the earth and the mast, and I'm not finding an isolating mount that goes into a normal ½" "light stand". So I've come up with this design to build. (Yay, I can't just buy it, so I have an excuse to spend some shop time!)
From 1" 6061 aluminum stock and 1" POM:
An aluminum stem/spigot that fits the tripod, with a 1" section above. In that section, an M14x1.5 threaded socket.
A POM threaded bushing; M14x1.5 on the outside, M10x1.5 on the inside, with a 2mm flange on top
An aluminum piece on top with M10x1.5 screw threads on both end, and six 4mm holes drilled around it to accept 4mm banana/bullet plugs. The M10x1.5 is to match the JPC-12 feed base.
I intend to raise only two radials, but six holes give me a chance to change my mind later, and even with just two they make it easy to line up the holes well enough with where I want the radials to run. (An elevated radial is worth about 8 ground-coupled radials.)
My idea is to machine the POM threads a little over-size, so that the whole thing is hard to screw together and locks together kind of like a nylon locknut. The larger diameter of the aluminum pieces will be knurled to facilitate this. It's meant to be strong enough to hold as much as 30 feet / 10m of loaded vertical, including JPC-12 riser sections, JPC-12 loading coil, and up to 25' whip.
Removed some obviously unnecessary metal from the design to make this lighter before I bother to make this.
It's so hard to sense scale, but this is 25mm OD. The flanges on the bottom are ½". The holes drilled into the side are 4mm to fit 4mm banana/bullet connectors. The yellow layer of insulation between the two metal parts is 2mm thick.
Looking forward to actually making this, so I can take a picture with a banana connector for scale. Maybe a banana too! 😉
Michael K Johnson