38-15 Project

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38-15 Project

ipwizard
Senior Member

Posts: 335
Threads: 50
Joined: Apr 2011
City: Apple Creek State, Province, Country: Ohio

08-10-2012, 01:25 PM

Just started on a Philco 38-15 a couple weeks ago. Got all the caps replaced along with all of the out of tolerance resistors. It comes up and plays but there is a bad 60hz hum coming coming out of the speaker. I used my signal tracer and traced back through the circuit and I don't pick it up in the 6A7, but I do pick it up on the 78 tube. I haven't been able to track down where that hum is getting into the audio from.

If anyone had any ideas let me know.

I have double checked that the E-caps are connected correctly.

Schematic here:
http://www.nostalgiaair.org/PagesByModel...013239.pdf

-Keith

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Messages In This Thread

38-15 Project - by ipwizard - 08-10-2012, 01:25 PM

RE: 38-15 Project - by Chuck Schwark - 08-10-2012, 01:32 PM

RE: 38-15 Project - by codefox1 - 08-10-2012, 02:02 PM

RE: 38-15 Project - by Chuck Schwark - 08-10-2012, 03:22 PM

RE: 38-15 Project - by ipwizard - 08-10-2012, 04:40 PM

RE: 38-15 Project - by ipwizard - 08-13-2012, 01:05 AM

RE: 38-15 Project - by ipwizard - 09-30-2012, 12:39 AM

RE: 38-15 Project - by Ron Ramirez - 09-30-2012, 06:42 AM

RE: 38-15 Project - by TA Forbes - 09-30-2012, 08:32 AM

RE: 38-15 Project - by ipwizard - 09-30-2012, 12:46 PM

RE: 38-15 Project - by Arran - 09-30-2012, 08:41 PM

RE: 38-15 Project - by ipwizard - 10-01-2012, 01:12 PM

RE: 38-15 Project - by Chuck Schwark - 10-01-2012, 03:56 PM

RE: 38-15 Project - by ipwizard - 10-01-2012, 06:32 PM

RE: 38-15 Project - by Chuck Schwark - 10-02-2012, 08:58 AM

RE: 38-15 Project - by Ron Ramirez - 10-02-2012, 09:03 AM

RE: 38-15 Project - by ipwizard - 10-02-2012, 02:13 PM

RE: 38-15 Project - by Ron Ramirez - 10-02-2012, 02:23 PM

RE: 38-15 Project - by codefox1 - 10-02-2012, 02:24 PM

RE: 38-15 Project - by TA Forbes - 10-02-2012, 04:14 PM

RE: 38-15 Project - by LASJayhawk - 10-02-2012, 09:53 PM

RE: 38-15 Project - by ipwizard - 10-03-2012, 12:14 AM

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