Phil Landmeier @shuttersparks@social.cleverlibre.org

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 I remember those too. Acorn tubes. They were rare outside of things like missile guidance systems.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 Feel is extremely important to me since I like to use straight key for extended periods.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 It wasn't that long ago that military organizations placed considerable importance on Morse communications. It would really suck to lose a battle because your radioman's key broke down. With the KT4 key I love so much, the Chinese took this to extremes and I'm glad.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 Holy Toledo? My mom used to say that. Lol.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 Yep. It's probably not a bad key if you clean it up and clean the contacts.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 Ah, whatever plastic pellets they could lay hands on cheap that day. lol. Okay, yeah, that's Soviet. So you have a collector there.

@SrRochardBunson @ClaraListensprechen@universeodon.com @Ralph058 @sergio_101 Yeah. And we see it in Ukraine today. Ukraine is now littered with unexploded bombs and missile warheads. Half their stuff doesn't even go off when it hits.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101

Is this it?

@ClaraListensprechen@universeodon.com @SrRochardBunson @Ralph058 @sergio_101 Well, and the increasing rarity of electronics-grade material. All the good stuff has been mined already.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 Well, I hate to point this out, and I hate to paint with a broad brush, but the Chinese culture has a strong element of fine craftsmanship in it, kind of like Germans or Ukrainians. The Russians don't do craftmanship. They're okay with making junk.

Well, there I've gone said it.

@SrRochardBunson @ClaraListensprechen@universeodon.com @Ralph058 @sergio_101 Yes it does. Mica was pretty common on high-powered solid state stuff in the 60s and 70s. It's become expensive today and I guess there are substitutes like silicone that are acceptable.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 Hmm.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101

Here's my every day key and the best straight key I've ever used. It's excellent. It's a Chinese PLA (People's Liberation Army) key and they didn't mess around on the important parts of the design. And it's built like a battle tank. The closest to it is the Bencher RJ. I bought four of them to make sure I'm never without. And a couple more to give to ham friends.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 Sorry, man. Lol.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 The more I look at it, the more convinced I am. Ima bet money it's Soviet.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 Any markings on it? In Russian, maybe?

@SrRochardBunson @ClaraListensprechen@universeodon.com @Ralph058 @sergio_101 Yup, there too. Also as heatsink insulators under high powered transistors and diodes. It's still the best material, I believe, but I could be wrong about that.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 That key looks familiar but I can't place it. I want to say Soviet era Russian, 1960s or 70s.

@SrRochardBunson @ClaraListensprechen@universeodon.com @Ralph058 @sergio_101 Yes. Mica (the mineral, but carefully selected sheets of it) has been used for like 100 years to make capacitors. No capacitor dielectric can equal its performance, yet.

These fabulous characteristics of mica used to be very important in the design and manufacture of "analog" radios. Their importance is far less today for two main reasons. Modern radio designs don't depend on capacitor performance to maintain frequency stability. 1) We use digital methods to produce extremely precise frequencies locked to a quartz crystal reference. 2) Transmitters are solid state and run on low voltages so the high voltage capability of mica is unimportant. You can use any old material for coupling caps.

Mica still shines in certain niche applications like high powered radio transmitters like 250 kW and 500 kW shortwave transmitters. Those still use vacuum tubes that are supplied with 10,000 to 15,000 volts at 10, 20, 30 amps. Here you'll find mica caps. Some are the size of a basketball and weigh 25 pounds.

@ClaraListensprechen@universeodon.com @Ralph058 @SrRochardBunson @sergio_101 Yup, like the MT11 key I mentioned. It was made by various companies during WW2 but mine is a genuine Bendix.

It was the same with guns. Even the Singer sewing machine company was turning out firearms during WW2.