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@trevorflowers @chrishuck In aviation, safety-critical nuts and bolts are typically safety-wired or use cotter pins, with castellated nuts and/or drilled/safety bolts. There are often dissimilar metals in use with different rates of expansion, which I understand makes torque unreliable (I expect this is a substantial difference with the chemical plants).

Pairs of nuts or bolt heads are often safety-wired together with tight-wise winding (wrapped clockwise for right-handed threads) so that they protect each other from unwinding.

For cotter pins to lock nuts in place, bolts will have a hole (or, I think, sometimes a slot) for the cotter pin to go through a castellated nut and lock it in place.

Good to see the AP calling out Kennedy's lies.

https://apnews.com/article/fact-check-kennedy-rfk-congress-senate-vaccines-covid-deaths-hospitals-efa457f139dabcce6f54c0ac2c590512

Wait. Here's another Kennedy with a different fruitcake health idea.

https://www.livenowfox.com/news/cesium-137-shrimp-aliens-john-kennedy

"Saying I'm anti-vaccine is like saying I'm anti-medicine," Kennedy said

Yes, Mr. Kennedy. Yes, it would be. And it would be true. "Anti-medicine" is a great and fitting way to describe you.

https://www.npr.org/sections/shots-health-news/2025/09/04/nx-s1-5528966/rfk-kennedy-hearing-covid-vaccines-cdc

I really didn't like the mechanics of this prior iteration, either. Too much leverage on the BNC connector in the radio. That and the high voltage on bare terminals right next to my fingers.

I'll be happier setting this up now!

This is the third full build iteration of my miniature #QRP unun supporting both EFHW and "random wire" antennas. At this point, it is still fiddly to build, but I'd expect an experienced #HamRadio DIY / homebrew enthusiast to find the build not terribly difficult.

There's nothing hugely new here. It's just small (and thus power-limited!) and has a tap for a random-wire antenna as well as the primary EFHW. It is optimized for EFHW; the RW tap is an extra. It could be made significantly smaller by ditching the RW tap, but I like the flexibility afforded by the extra tap, and it still disappears into the bag. The whole thing, including the coax and BNC connector, weighs 27g.

Bill of Materials, build instructions, STEP files for printing, and FreeCAD files for modifying are now all available:

https://gitlab.com/mcdanlj/QRPUnun

Here is a video of me sending CQ POTA DE KZ4LY at 20WPM with my new key. Well, it's a video of my radio while I'm sending with my new key.

It sounds very clicky in the video because of the quiet environment and the phone taking the video "enhancing" the audio. It's actually very quiet in real use. It's the quietest key I have; quieter than my Kent or Putikeeg for example.

Here is my current morse code key with all its parts prior to assembly, as well as after assembly. In addition to these parts, you need:

• 3D printer to print the key
• Wire stripper
• Soldering iron
• Wrench or pliers for the 1/8" fixing nut
• Spiral-flute M3 tap
• Appropriate cutter and files or sander to make optional stabilizing rod (don't use your wire cutters for stainless steel unless you want to destroy them!)

I have sources for all the parts except the (commodity) stranded wire linked in the README.

One of the main things in the way of publishing this as version 1.0 is taking all the pictures I just took (far more than these) and assembling them into an assembly guide.

I have released version 0.5 Beta of my #HamRadio single-paddle #Morse key.

I added optional stabilizer bars for which I recommend 3mm stainless rod, to counteract torque from the center of pressure on the grip being above the spring. (That twisting has been the main thing about the key that has caused me to inadvertently send wrong code as the head of the center contact screw bounces off the edge of the dit or dah screw.)

I made the lever more compact, which required adjusting the range of default spring force from the integrated springs. I also removed the heaviest weight that no one liked.

The README has instructions, information on options for required hardware, and complete documentation for all the parameters that drive this single key system.

This is a release candidate for version 1.0. If you like CW / Morse code and 3D printing, and either like single-paddle keys or would like to try one, please give this a shot and tell me how you like it! It's been successfully tested with PLA, PETG, and ABS, so it should work with most common filaments. Just don't leave it in a hot car if you print with typical PLA!

Feel free to ask questions in a 🧵 thread here!

I celebrated a day off work today in part by doing #POTA. I finally activated the park closest to my house — a short ten minute drive away. This time, using a measly 5W on CW, into a wire thrown up into a tree (40m EFHW), in a low area next to a stream because that's where the park is.

I needed just one more QSO to successfully activate, and then got a 539 signal report from a patient hunter in Sweden. Patient in particular because I had only one contact outside the east US, and thought I'd copied poorly. I was so confused that I sent SRI CALL AGN? before I realized what I was hearing.

I'm still a CW greenhorn, and some of the other operators also had to be a little patient. I ran 15WPM. I don't think anyone was running much over 20WPM calling back, and with a few ? and AGN? for some repeats, I got through without having to request QRS. I hope by the end of the year to run 20WPM comfortably, including handling pileups.

#HamRadio continues to blow my mind.

@FreeCAD I've been busy in #FreeCAD making design after design for a DIY remotely operable variable capacitors with an eye to designing something that is easy and reasonably inexpensive for anyone to make. I think I'm getting close to something I'm satisfied with. Most people don't need this, but it's actually pretty useful in #HamRadio. Hams tend to scrounge for large variable capacitors and then bend their designs to fit whatever they can turn up; this is parametric so a ham can choose desired parameters, get some PCBs printed, buy some common parts, 3d print a few others, and have a working butterfly capacitor.

The trickiest part will probably be the workflow from FreeCAD design into #KiCAD to create the gerbers to send off to make the PCBs. That will take some manual work for anyone who wants to change the design parameters, beyond just changing some numbers in a VarSet.

This is about 120mm on a side. It uses printed PCBs for the fixed capacitor plates, PTFE film for the dielectric, and laser-cut copper for the rotors. A 3d-printed 60-tooth GT2 pulley for the effector (don't want metal there; it will change the behavior of the capacitor!) and a 16-tooth pulley on a nema17 pancake stepper to drive it. I haven't modeled the belt, but that's kind of the trivial part to imagine, I hope!

I'm looking for inexpensive linear actuators. I bought a $15 unit that uses an M3x0.5mm threaded rod and it's not horrible, but the effector has a lot of backlash. This has more stroke than I need; I only need about 65mm of stroke. But I wouldn't want to be particularly larger than this. Roughly 20mm x 20mm x 100mm would be my target envelope.

I'll fall back to using this with backlash compensation if necessary, and I don't want to spend a lot, but if someone knows of something substantially better for not too ruinously much more money, I'd like to become aware of it.

(This is to control a high voltage variable capacitor I'm designing for a #HamRadio small transmitting loop antenna. I'm trying to make the whole thing sufficiently inexpensive that a ham doesn't really have to think twice about making one.)

#DIY

This afternoon's 10–15W SSB #POTA #HamRadio activation. Three QSOs on 15m including Dominican Republic. Then when I needed just one more QSO to successfully activate US-4857 for my first time, I got Germany with a 33 signal report on 15W. ️ Most of the QSOs were on only 10W.

All this on my home made inverted V linked dipole pulled up into a tree.

It was a gorgeous day to sit outside under the trees. Despite being August in North Carolina, the temperature was reasonable and it wasn't too humid. I can't wait for a fall filled with POTA activations and ham public service driving around helping with communications at bicycle races.