SX-636 power supply cap discrepancy

audiojones

Jonesin' for audio
Subscriber
Hi -
I'm in the process of refreshing an SX-636 and came across a cap value discrepancy on the power supply board. C-12 on board AWR-060 B is 10uf 16v but it's listed on the schematic and the BOM list as 220uf. I don't see a service supplement for this particular receiver, was this a production line change or a previous tech's error? Serial number is VA3927xxxx (January of '75, fairly late model I guess) and it has been working just fine with the 10uf cap in there. I replaced it with a 10uf 50v UPW but I've got 220's on hand too. It looks like it's been in there from day one, no glue ring or signs of a larger 220uF cap on the board. Whaddya think? :dunno:

Add-on: The power supply board also has AU LX stamped on it if that makes any difference.
 
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keep the 10, it modiifies the load response of the power regulator and IMO 220uf is wayyyy out of line.

In the 737 the corresponding cap is 22 uf, (c17 awr-058) so 220 could be a typo/error...
 
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Thanx Mark, will do. All ps voltage measurements are spot on, and judging by the photos of the ps board in the sales brochure it looks like C-12 was always a small cap from the beginning.
 
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