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Philco 37-690
#40

Why not separate the 3K and 2.2K resistors so they do not heat the same concentrated location on the chassis? You might leave the 2.2K where it is and relocate the 3K to the right side of the chassis where there is no resistor now. The 3K dissipates the most power and generates the most heat.

In the end a certain amount of heat has to be dissipated, but if it can be distributed more evenly over the surface of the chassis, a lower peak temperature will result.

These resistors form part of a voltage divider for the power supply, providing B+ and bias for the circuits, while at the same time serving as a bleeder. They also provide a load to produce the required field current for one of the tweeters. There is no easy way to redesign it.

In any case, keep in mind that the heat generated now is no more than it was when the set was new, and was then considered acceptable by the designers.


Messages In This Thread
Philco 37-690 - by Ron Ramirez - 05-30-2014, 08:22 PM
RE: Philco 37-690 - by morzh - 05-30-2014, 08:31 PM
RE: Philco 37-690 - by Eliot Ness - 05-30-2014, 08:42 PM
RE: Philco 37-690 - by morzh - 05-30-2014, 09:16 PM
RE: Philco 37-690 - by Ron Ramirez - 05-30-2014, 09:29 PM
RE: Philco 37-690 - by Eliot Ness - 05-30-2014, 09:41 PM
RE: Philco 37-690 - by morzh - 05-30-2014, 10:49 PM
RE: Philco 37-690 - by Arran - 05-31-2014, 02:10 AM
RE: Philco 37-690 - by Eliot Ness - 05-31-2014, 08:14 AM
RE: Philco 37-690 - by Joeztech - 06-01-2014, 08:58 PM
RE: Philco 37-690 - by Ron Ramirez - 06-02-2014, 05:32 AM
RE: Philco 37-690 - by Phlogiston - 06-02-2014, 09:45 AM
RE: Philco 37-690 - by Ron Ramirez - 06-02-2014, 09:53 AM
RE: Philco 37-690 - by Phlogiston - 06-02-2014, 12:04 PM
RE: Philco 37-690 - by morzh - 06-02-2014, 12:28 PM
RE: Philco 37-690 - by Phlogiston - 06-02-2014, 12:34 PM
RE: Philco 37-690 - by bfrohwein - 06-02-2014, 01:03 PM
RE: Philco 37-690 - by Phlogiston - 06-02-2014, 02:09 PM
RE: Philco 37-690 - by Ron Ramirez - 06-02-2014, 05:21 PM
RE: Philco 37-690 - by Phlogiston - 06-02-2014, 09:03 PM
RE: Philco 37-690 - by bfrohwein - 06-03-2014, 12:14 AM
RE: Philco 37-690 - by Eliot Ness - 06-03-2014, 09:10 AM
RE: Philco 37-690 - by Ron Ramirez - 06-13-2014, 08:11 AM
RE: Philco 37-690 - by y2kbruce - 06-13-2014, 03:09 PM
RE: Philco 37-690 - by morzh - 06-13-2014, 03:10 PM
RE: Philco 37-690 - by Ron Ramirez - 06-13-2014, 03:59 PM
RE: Philco 37-690 - by Ron Ramirez - 07-01-2014, 09:28 PM
RE: Philco 37-690 - by Arran - 07-01-2014, 11:44 PM
RE: Philco 37-690 - by Ron Ramirez - 07-02-2014, 05:31 AM
RE: Philco 37-690 - by jerryhawthorne - 07-02-2014, 03:37 PM
RE: Philco 37-690 - by Ron Ramirez - 07-03-2014, 10:58 PM
RE: Philco 37-690 - by morzh - 07-03-2014, 11:19 PM
RE: Philco 37-690 - by Ron Ramirez - 07-04-2014, 11:45 AM
RE: Philco 37-690 - by morzh - 07-04-2014, 12:40 PM
RE: Philco 37-690 - by Ron Ramirez - 07-05-2014, 07:29 AM
RE: Philco 37-690 - by morzh - 07-05-2014, 09:40 AM
RE: Philco 37-690 - by Ron Ramirez - 07-17-2014, 08:55 PM
RE: Philco 37-690 - by Mondial - 07-17-2014, 09:56 PM
RE: Philco 37-690 - by Ron Ramirez - 07-18-2014, 05:51 AM
RE: Philco 37-690 - by Mondial - 07-18-2014, 06:43 AM
RE: Philco 37-690 - by Ron Ramirez - 07-18-2014, 07:26 AM
RE: Philco 37-690 - by Ron Ramirez - 07-18-2014, 07:30 AM
RE: Philco 37-690 - by Mondial - 07-18-2014, 08:02 AM
RE: Philco 37-690 - by morzh - 07-18-2014, 09:10 AM
RE: Philco 37-690 - by Ron Ramirez - 07-18-2014, 10:00 AM
RE: Philco 37-690 - by Phlogiston - 07-18-2014, 10:01 AM
RE: Philco 37-690 - by Mondial - 07-18-2014, 03:12 PM
RE: Philco 37-690 - by morzh - 07-18-2014, 04:03 PM
RE: Philco 37-690 - by y2kbruce - 07-18-2014, 05:37 PM
RE: Philco 37-690 - by Ron Ramirez - 07-18-2014, 05:48 PM
RE: Philco 37-690 - by morzh - 07-18-2014, 06:33 PM
RE: Philco 37-690 - by Ron Ramirez - 07-18-2014, 07:21 PM
RE: Philco 37-690 - by Ron Ramirez - 07-20-2014, 09:16 PM
RE: Philco 37-690 - by Ron Ramirez - 07-21-2014, 07:21 PM



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