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The Fisher 440-T FM Receiver
#79

Ron,

Bridge rectifier should be fine. New caps was a good idea.

A couple of things to try:

Put scope on AC coupling so you can go to say 0.2V/div and see if you have any ripple/hum on the DC voltages. A good test of the caps.

Next without any signal input at all turn volume to 0 and check with DVM for DC voltage on speaker terminals. Most manuals have you adjust for 0-0.5V. This is to balance the +/- rail voltages through the output transistors to reduce clipping and maximize output. Sometimes this is also called biasing.

As for Q11 traces you attached these look normal for a channel being driven into clipping. On several vintage receiver repairs over my amateur career it's normal to see clipping start around 12 o'clock on the volume control. That's why going to 1-2 PM on the volume control starts to sound distorted.

As for Q9 that sure looks like it's output is low and being driven to clipping much earlier.

The one thing on this receiver that I haven't worked with is the audio output transformers. All the SS receivers I worked on were directly coupled. May not hurt to check the DC resistance and/or inductance of the transformers without anything connected to see if one of the windings is wounded.

Last thought, am I correct in assuming you recapped the output board/circuit? These are usually ticking time bombs in 35-40 year old receivers.

Thanks,

Mike

Cossor 3468
GE 417A
Philco 118H
Radiola 17/100
Scott 800B6
Silvertone 6130
Stromberg 535M
Truetone D1952



Messages In This Thread
The Fisher 440-T FM Receiver - by Ron Ramirez - 03-01-2014, 10:51 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-01-2014, 10:54 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-01-2014, 11:00 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-01-2014, 11:08 PM
RE: The Fisher 440-T FM Receiver - by skyscraper - 03-01-2014, 11:13 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-01-2014, 11:18 PM
RE: The Fisher 440-T FM Receiver - by skyscraper - 03-01-2014, 11:26 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-02-2014, 09:37 AM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-02-2014, 08:08 PM
RE: The Fisher 440-T FM Receiver - by BrendaAnnD - 03-02-2014, 10:22 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-02-2014, 10:26 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-02-2014, 10:34 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2014, 10:10 AM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2014, 11:08 AM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-03-2014, 11:20 AM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2014, 12:54 PM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-03-2014, 01:17 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2014, 01:28 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-03-2014, 01:51 PM
RE: The Fisher 440-T FM Receiver - by BrendaAnnD - 03-03-2014, 02:46 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2014, 04:25 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-03-2014, 04:48 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2014, 04:51 PM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-03-2014, 05:16 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2014, 06:50 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2014, 06:51 PM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-03-2014, 07:21 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2014, 09:53 PM
RE: The Fisher 440-T FM Receiver - by BrendaAnnD - 03-03-2014, 10:56 PM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-03-2014, 11:39 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-04-2014, 10:53 AM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-04-2014, 11:14 AM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-04-2014, 07:58 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-10-2014, 08:45 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-13-2014, 05:53 AM
RE: The Fisher 440-T FM Receiver - by BrendaAnnD - 03-13-2014, 10:09 AM
RE: The Fisher 440-T FM Receiver - by morzh - 03-13-2014, 10:21 AM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-13-2014, 04:40 PM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-13-2014, 06:05 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-13-2014, 07:01 PM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-13-2014, 08:05 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-13-2014, 08:08 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-13-2014, 08:10 PM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-13-2014, 08:36 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-13-2014, 08:37 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-13-2014, 08:43 PM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-13-2014, 08:50 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-13-2014, 08:55 PM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-13-2014, 09:07 PM
RE: The Fisher 440-T FM Receiver - by BrendaAnnD - 03-13-2014, 10:12 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-15-2014, 10:07 AM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-15-2014, 11:22 AM
RE: The Fisher 440-T FM Receiver - by Mondial - 03-15-2014, 11:34 AM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-15-2014, 12:16 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-15-2014, 06:35 PM
RE: The Fisher 440-T FM Receiver - by BrendaAnnD - 03-15-2014, 09:01 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-15-2014, 10:39 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-16-2014, 03:41 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 10-04-2014, 10:34 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 02-20-2015, 11:33 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 02-26-2015, 10:12 AM
RE: The Fisher 440-T FM Receiver - by morzh - 02-26-2015, 12:09 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 02-26-2015, 09:05 PM
RE: The Fisher 440-T FM Receiver - by morzh - 02-26-2015, 11:17 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2015, 12:46 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-03-2015, 01:07 PM
RE: The Fisher 440-T FM Receiver - by PhilcoMike - 03-03-2015, 03:37 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2015, 03:42 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-03-2015, 04:19 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-03-2015, 04:43 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2015, 09:56 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-03-2015, 10:39 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2015, 10:46 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-03-2015, 10:52 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-03-2015, 10:57 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-03-2015, 11:04 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-03-2015, 11:12 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-04-2015, 11:03 AM
RE: The Fisher 440-T FM Receiver - by PhilcoMike - 03-04-2015, 12:50 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-04-2015, 02:21 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-04-2015, 02:36 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-04-2015, 02:44 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-04-2015, 06:41 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-04-2015, 06:44 PM
RE: The Fisher 440-T FM Receiver - by PhilcoMike - 03-06-2015, 02:17 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-06-2015, 02:50 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-11-2015, 02:49 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-11-2015, 03:44 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-11-2015, 03:58 PM
RE: The Fisher 440-T FM Receiver - by morzh - 03-11-2015, 06:46 PM
RE: The Fisher 440-T FM Receiver - by codefox1 - 03-14-2015, 10:26 AM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-14-2015, 10:15 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-17-2015, 08:34 PM
RE: The Fisher 440-T FM Receiver - by PhilcoMike - 03-18-2015, 01:17 PM
RE: The Fisher 440-T FM Receiver - by Ron Ramirez - 03-18-2015, 01:53 PM



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