I know...what was I thinking. I have another model 89L (1934 Code 123, Run 13). I have completed the wood restoration, had the speaker re-coned, changed out all the caps, etc. I then brought the beast up on my variac. I should have known...nothing. I proceeded to check some voltages. I had no plate voltage on my 44 (RF) or my 36 (DET.OSC). Low and behold, I have not one but two open coils. One coil open on the Detector and one open on the Oscillator. Now that I have you all sympathizing with me, are there replacement coils available somewhere? I have not attempted to re-wind a coil, and I am a little intimidated. I guess as a last resort I would re-wind them.
As always, any help from the phorum would be appreciated!
Before you even go to those coils, and because you did not mention these steps:
1. Check your transformer outputs what it should. For this, remove the rectifier tube (or even all the tubes) and see the High voltage coil end-to-end (will be on 600V level), and the filament voltage (whatever it is that should be there, see your tubes) and the filament voltage for the rectifier tube.
2. Make sure the filter caps are discharged and measure across them, to look for short.
3. Then put all tubes in, including the rectifier and hook up the speaker, and see if there is any high voltage there anywhere at all.
4. If yes and the tubes light up, then see why it is not where it should be (yes, coils open etc).
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
An open interstage coil (6) would keep B+ from the 44 RF amp plate.
However, your not having plate voltage at the 36 tube is a bit puzzling. Normally when the oscillator coil (14) fails, it is the cathode "tickler" winding (left-most winding of that coil on the schematic, 5.25 ohms) that goes open.
I suppose it could be corroded so badly from that nitrocellulose insulator Philco used back in the day that it may have caused the plate winding (5.07 ohms) to fail also. Check those out.
Both of those are open. The coil that should read 1.68 ohms on 6 is open. The coil that should read 5.07 ohms on 14 between the the 36 Plate and cap #15 is also open.
I guess at this point, I'm looking for some re-winding videos or "how to's" on this. Does anyone know how many turns on each of these?
Re-wound both coils last night. They turned out really good for my first time. I attached a before after pic. Cant wait to get them back into the chassis.
