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Rock on! I don't run into a lot of bum channel-digit resistors, but that's far and away the cheaper, better fault to fix. Resistors are usually less likely to fail than LED displays. Just goes to show that the odds aren't always the whole story. 73

Three see-ecks four hundred? Cool choice. Has a lot of power gain for a triode. Probably also has the number 8874 on it. Be nice to it, they've been discontinued for a while. 73

It's probably built from separate plastic sections with a visible seam between them. We take the tip of a box-knife blade to separate the sections just enough for the stream from the straw on a can contact cleaner to penetrate. Doesn't take all that wide a gap to get the pressurized liquid in...

Had a customer years ago who made his own coax jumpers. His claim to fame was a carefully-crafted ball of solder on the tip of the center pin, a bit bigger around than the pin diameter. Thought it would improve the connection. What it did was to waller out the SO-239s in everything he brought...

With any luck, the burned resistors resulted from a lamebrain overdriving it some time in the past, not from bad tubes. So far so good. 73

It should. 73

Yellow part is a plastic film capacitor, 0.22uf 600 Volt rating. 73

Kinda reminds me of "first car syndrome". A guy gets sentimental about the make and model of his first wheels. Decades after that first car went to the scrap yard he wants one like it now that he can afford it. Never mind that the coupe he drove in high school can be found now only in the form...

Hey, I'm ready for the next installment! 73

Um, the cap on the top is the anode (plate). Pin 4 is G2, the screen grid. Runs with a positive DC voltage. Maybe 100 Volts maybe more. Pin 8 is the cathode and G3 both. Goes to ground through a 12-ohm resistor, looks like. Having a hard time orienting pin numbers in the pic. The key slot is...

Those look like the kind of resistor that gets toasted when a tube breaks down. Not so different from the 10-ohm base resistor on a 2SC2879. I'd be wondering how many of those tubes show that purple internal glow from gas in the vacuum when you key it. Its a favorite way for 60 year-old tubes...

Ever hear the advice that begins with "If it looks too good to be true"? Color me skeptical. Ever get the feeling you're being jerked around? Gettin' that feeling. 73

That was a bit of an oddball. Had two fat 3PDT open-frame relays, one for the antenna and one for the preamp. Haven't seen one of those in 30 years. I'll poke about at the shop for any paper info. Came up dry looking online. 73

This is how the Troy Radio synthesizer implements the clarifier. Don't care for the conversion lag, though. The discrete up and down steps you'll hear turning it slowly reveal the speed of the analog-to-digital conversion. I would prefer a second rotary encoder with smaller steps. Probably...

Way cool! Hadn't stumbled onto Biricha yet. Thanks! 73

That is exceptional! Fingers crossed it all works the first production run. 73

The Tone control won't be a linear-taper control like you need for the clarifier. It will have a "log" or audio taper on the resistance element inside. This would scrunch your clarifier coverage close together at one end of the control. RF gain control will be a linear taper pot. 73

Didnt't think to ask if you had set the zero-signal DC bias current for the new driver and final. If it's set too high that can cause odd behavior. 73

Maybe not so much the solder but accumulated rosin. Some kinds can absorb humidity and become conductive. But hey, you fingered it out. Rock on! Congratulations for sticking with it. 73

Here's a before picture of the carrier oscillator section in a Cobra 138XLR mobile CB. The X1 socket is empty because the crystal died. Finding a 48 year-old replacement can probably be done, but I'm going a different route. This issue keeps coming up, and I have tired of looking under rocks for...