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Philco 643 restoration
Arran
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#14

09-05-2011, 01:24 AM
You can usaully tell if the coil has been smoked by a lightning strike, the whole primary winding will look black. I recently ran into this in a lake 40s Viking battery radio (Dominion Electrohome) although it is broadcast band only so it doesn't have any extra taps. I'm not sure why they would connect a resistor between a dead coil and ground, the usual quick repair is to connect a capacitor from the antenna terminal to the secondary in some way. I've also seen this happen with an oscillator coil, a paper cap shorted out between the top of the winding and the B+, since most coil windings are made of very fine wire the internal resistance causes them to burn up. It was a rather stupid design in my opinion, much like the tone controls with B+ on the wiper capacitor.
Regards
Arran
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Messages In This Thread
Philco 643 restoration - by Bob Andersen - 08-04-2011, 10:13 PM
Re: Philco 643 restoration - by Bob Andersen - 08-05-2011, 01:44 AM
Re: Philco 643 restoration - by Ron Ramirez - 08-05-2011, 06:38 AM
Re: Philco 643 restoration - by TA Forbes - 08-05-2011, 12:36 PM
Re: Philco 643 restoration - by Ron Ramirez - 08-05-2011, 12:59 PM
Re: Philco 643 restoration - by Bob Andersen - 08-05-2011, 07:28 PM
Re: Philco 643 restoration - by TA Forbes - 08-05-2011, 10:07 PM
Re: Philco 643 restoration - by Bob Andersen - 09-02-2011, 04:29 PM
Re: Philco 643 restoration - by TA Forbes - 09-02-2011, 11:39 PM
Re: Philco 643 restoration - by Ron Ramirez - 09-02-2011, 11:43 PM
Re: Philco 643 restoration - by Bob Andersen - 09-03-2011, 12:30 AM
Re: Philco 643 restoration - by Ron Ramirez - 09-03-2011, 07:59 AM
Re: Philco 643 restoration - by 7estatdef - 09-03-2011, 11:44 AM
Re: Philco 643 restoration - by Arran - 09-05-2011, 01:24 AM
Re: Philco 643 restoration - by Bob Andersen - 09-07-2011, 11:11 PM



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  1. The PHILCO Phorum
  2. Philco Radio Discussions
  3. Philco Electronic Restoration