I have to rewind or replace one of the primaries on the input antenna coil. This was a victim of the original cheapo power supply. Apparently the antenna terminal got grounded when the chassis was "hot." POOF -- smoke was released.
The bands do seem to sound better through thermatrons... And there is an undeniable 3-D aspect to working on these old rigs.
So yes, in a certain sense REAL RADIOS GLOW IN THE DARK.
Bill, I think that as long as you don't work on it in the car port in your bare feet you'll be fine! Good luck with it and don't blame Grayson too much. I think it was destined to come back in the house eventually. The radio gods have been whispering in your ear!
Ciao! & 73, Armand
Ciao! & 73, Armand
I’ll take the blame, no problem!S38 is nice to work on, plenty of room, no magnifying glass required. But I have to admit I am not a big fan of working on low cost AC line powered “raft-anchors” (too little for a boat). Definitely give it a isolation xformer and replace the filter cap(s). If it doesn’t weight 50+lbs, a bit lightweight for me.
If you need a good thermatron homebrew project (and who doesn’t really), I’ll send you plans for a nice 4-thermatron (including compactron) AM/CW 20/40M 5 watt transmitter I am finishing up (90% of the work is “finishing up”). Designed from scratch. Actually works. Uses a new construction technique I’ve been working on.
As I read about your next project – kept thinking –you can put lipstick on a pig BUT it is still a pig. I had one and put an isolation transformer on the front end –but found I was showing signs of carpal tunnel syndrome on my left hand as I kept retuning the radio because it drifted so much. Have fun.
I don't know. Simplicity is a virtue, and this thing is pretty simple: RF amp, mixer, LC oscillator, detector, audio amps. Broad as a barn door with just two 455 kc IF transformers for the filter. Lots of room on the chassis.
As for drift, my little 6u8 RX with LC oscillators in both LO and BFO settles down very nicely.
I surely didn’t mean to denigrate your next homebrew project and perhaps it was that the one I had was a dud in the lot.
But I then moved up to the SX-99 and was in tall clover. Besides today we have some things we can do to enable “tamer” oscillators. So why not? You need to team that up with the M^3 and make some contacts.
Pete: I KNEW you would try to get a synthesizer of some sort inside the S38-E. But I say NO! I had a lot of fun getting the LC oscillators in my 6U8 rig to tune exactly where I wanted them to tune. You know, play around with the cap in series with the main tuning cap to change the tuning rate (better than removing plates -- they are hard to put back on!). Then changing the values of the L and C elements to get the thing to oscillate in the desired range. Then wrap it all up with some Dymo tape on the 1/2 CD "tuning dial." Sure, I know, that would have been a few keystrokes on the Arduino, but somehow this old way puts you closer to the physics, closer to the electrons. Take a look at the e-mail about Wooden Boats, VFOs and PTOs on yesterday's SS blog.
The "widow maker" potential of the S38-E was apparently on the minds of the guys who designed the cabinet. The whole box and the front panel are all very carefully insulated from the chassis. Plastic nuts!
Nice looking pig, by the way. She may appear on the blog soon.