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Philco 42-380 conflicting wiring vs schematic
#1
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Thanks for having me in the forum.  I collect radios and have restored several Philcos over the years.

I inherited a Philco 42-380 from my Dad.  It had never worked while he had it.  I know it is a pretty common one.  I am in the process of restoring it and am awaiting some parts at the present. 

While in the process of replacing  the original rotten rubber wiring I noticed that pin 5 (plate) of the 6X5 rectifier is tied to the ground connections of the two 71 audio output tubes.   There are no ground connections currently on pins 5 and 6 of the 71s which is in direct conflict with the schematic.  I know there is a history of 6X5 rectifiers destroying the main transformer.  I plan to replace it with two diodes to prevent that but wonder why the factory would have done this?  I assume it had to run with this configuration since there is no sign of it being done by a previous service.  The audio output transformer and speaker field coil were destroyed long ago by capacitor failures.


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