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power supply problems

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I am working on a console stereo. It is solid state and in the power supply I have 17vac on both sides of the transformer with -17vdc on one side of the rectifier circuit and -4vdc on the other side that should be +17vdc. I have not done this kind of stuff for years and have forgotten a lot but I do enjoy doing it. Any suggestions as to what is going on? I did replace two of the caps and checked a couple others that tested good according to my capacitor tester. Looked for anything else that might be wrong and didn't see anything burnt or bulging.
 
That sounds like the rectifier has failed, the diodes from transformer secondary to the +DC rail are open, disconnected (eg. dry joints), or a fuse has gone?
 
Sorry about the lack of info so I will correct that. It is a Sears Silvertone Console, Sam's Photofact set #958 folder #8. I did find a set to purchase so now have the schematic to look at. One more question while I am at it, there is a waffer switch that selects AM, FM, Phono, and Aux. There are no numbers printed on it. Can you tell me how to figure out which pin is number one? And then do the pin numbers go clockwise or counter clockwise? There are two sections to it and I am looking at it with the chassis upside down. The shaft is D shape and there is a locating pin through the chassis 90 degrees down on the left side looking at the shaft end. I have a wire attached to it with the other end just hanging. It was attached to a wire between a cap and a resister and according to the schematic is not supposed to have anything in between those two components. Thanks so much for the help.
Bruce
 
Model # on this Sears console is 8091 chassis # is 548.20010. Got the wafer switch figured out and found where the wayward wire went. Now I will change the two diodes in the power supply and hopefully will be all set. I will let you know how things went and hope for no more problems. As I think about things and don't get any sleep over it, stuff slowly comes back that I used to know. Just a question now, this stereo was made in 1968, does anyone know how the frequency display was made back then? It is linear and painted or printed or something on a piece of translucent plastic. Thanks again for the help and help jogging my memory. Bruce
 

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