03-06-2007, 09:11 PM
Sounds like you may have a bad tube in there or maybe a wrong type?? The A-B battery pack (P-60D11L) is 1.5 volts for A and 90 volts for the B portion.
The tubes 1A7G, 1N5G, and the three 1H5Gs are 1.5 volt, 250 ma. filament tubes. Someone may have messed with the wiring in there.
Check the schematic against the A+ buss. Every tube filament is tied to the A+ buss and the other ends are all ground, like the A- lead on the battery plug on the schematic.
1.5 volt tubes BARELY have a glow in a dark room when operating normally.
You may have other component and/or wiring issues as well - I'd trace out the whole set to be sure of not popping any tubes. Running those tubes at twice filament voltage may have weakend or severly shortened their life time. Find the error(s) in the set before powering it up again.
Check all resistors for any out of tolerance (+/-20% max) values and replace. Replace all caps too, if you have not already.
The tubes 1A7G, 1N5G, and the three 1H5Gs are 1.5 volt, 250 ma. filament tubes. Someone may have messed with the wiring in there.
Check the schematic against the A+ buss. Every tube filament is tied to the A+ buss and the other ends are all ground, like the A- lead on the battery plug on the schematic.
1.5 volt tubes BARELY have a glow in a dark room when operating normally.
You may have other component and/or wiring issues as well - I'd trace out the whole set to be sure of not popping any tubes. Running those tubes at twice filament voltage may have weakend or severly shortened their life time. Find the error(s) in the set before powering it up again.
Check all resistors for any out of tolerance (+/-20% max) values and replace. Replace all caps too, if you have not already.
Chuck Schwark,
The Philco Repair Bench
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http://www.philcorepairbench.com
