07-12-2021, 05:12 PM
You don't have to go to Radiomuseeeeeum. 
Comprehensive service info is available on this site. It is clearer and easier to download, too. Nathan has worked very hard to put this together.
https://philcoradio.com/library/index.php/service-info/
For model 531, you want Model 511 Series:
https://philcoradio.com/library/images/schem/511.jpg
https://philcoradio.com/library/download...l.%201.pdf

Comprehensive service info is available on this site. It is clearer and easier to download, too. Nathan has worked very hard to put this together.
https://philcoradio.com/library/index.php/service-info/
For model 531, you want Model 511 Series:
https://philcoradio.com/library/images/schem/511.jpg
https://philcoradio.com/library/download...l.%201.pdf
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Ron Ramirez
Ferdinand IN