Hurricane
Williams, 1991I finished rebuilding another power supply and this one is putting out +122V - 122V vs 90V as it should.... I did order a new round of components but all looks good to me... see picture... I replaced R2,R5 w/ 1.2K 1W R1,R4 w/ 39K 2w and ZR2 ZR4 1N4763 91V 1.3W see pictures plus caps...
any suggestions?
20181104_180644 (resized).jpg20181104_181527 (resized).jpgThat’s an odd one.
I don’t have a suggestion for you but I’m interested in what you find.
Your parts list looks good. I would have suspected the wrong Zener but those are right.
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Chris Hibler - CARGPB #31
http://ChrisHiblerPinball.com/contact/
http://www.PinWiki.com - The new place for pinball repair info
Quoted from johnrezz:Exactly what I thought.. Only guess I have is that these are not 90V.....
I had that thought too. But if they are marked correctly, it would be odd.
I wonder what would happen if you put 100V Zeners in?
Unloaded, the voltage varies off spec sometimes but not that much. Something is toast.
Zener diodes can be crudely tested just like a 1N4004 can. It won’t indicate breakdown voltage but we are just looking for short or open.
—
Chris Hibler - CARGPB #31
http://ChrisHiblerPinball.com/contact/
http://www.PinWiki.com - The new place for pinball repair info
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Round Hill, VA