The PHILCO Phorum

[attachment=5729]Problem is SOLVED and I may be a complete idiot !   MORZH -  I went away over the weekend with my family and kept thinking about this freakin radio the entire time.   Amongst other things -  you mentioned:  "The resistor in the middle is an NTC thermistor, it starts at about 1K and drops to 100 Ohm as it heats up".     I retraced all the caps I installed and checked all the wiring.  In my first restoration of this same radio, I noticed that  I left the thermistor (see picture) in place because, at the time,  I didn't know what it was and didn't want to mess with it.  In this most recent restoration, due to me misreading the "chassis - bottom view", I wrongly thought it was a capacitor and replaced it with a .1uf CAP. I thought the thermistor was just a weird looking capacitor.   When I got back from my trip,  I re lookeded at the chassis diagram and realized what I had done.  I soldered out the cap and put back in the thermistor -  and  VOILA -  it popped to life -  the tubes, the bulb.    So in the end, there was nothing wrong with the on/off switch.   I hooked up the speaker and the antenna and already it can pick up some am stations but I will still have to align it.     You really nailed the problem - so THANK YOU for your help.    Also, thanks to BrendaAnnD for jumping in with your help as well.
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To me those thermistors, which Philco marketed as a "Tube Saver", look more like an old fashioned radial lead resistor then a capacitor. In any event when I was a teenager I had a Sentinel that was working on, so I poked around under the chassis with an ohm meter and found out what I thought was a leaky mica capacitor, which I then removed. However when I tried powering the set up it did nothing, even though the tubes all lit up. It turned out that the leaky mica capacitor was the choke resistor in the B+ supply. But it was not too surprising that I was confused, a resistor that was packaged to look like a capacitor, but Micamold was a lousy company for doing things like that anyhow, like making wax paper caps look like mica caps, all of which were rubbish.
Regards
Arran

They even made resistors looking like mica caps. Dealt with one myself.
Really dumb idea....as if troubleshooting itself is not confusing enough.

(10-12-2014, 08:26 PM)morzh Wrote: [ -> ]They even made resistors looking like mica caps. Dealt with one myself.
Really dumb idea....as if troubleshooting itself is not confusing enough.

morzh & arran - 
OK - so now at least I feel  a little better that I'm not the only one to have made this type of mistake.  Thanks guys !