High voltage at U1 between pins 4 & 3 and 4 & 5

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High voltage at U1 between pins 4 & 3 and 4 & 5

Postby Matt... » Sun Mar 11, 2012 12:22 pm

Hello, I am measuring +- 25 volts and not +-14. I saw that someone else had the exact same problem and it was due to cold solder joints. I checked that all of the diodes and capacitors are oriented correctly and re-soldered anything that might have been cold, but I don't think I had any cold joints. I don't see any shorts either. Maybe there is a bad capacitor? I don't have a capacitance setting on my DMM so I'm not really sure what the next step in troubleshooting is. Any help would be greatly appreciated.
Matt...
 
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Postby tpryan » Mon Mar 12, 2012 6:38 am

If you can't get to +/-18V with R25 and R29, you've almost certainly done something wrong around the voltage regulators. Check your work carefully.
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Postby Matt... » Mon Mar 12, 2012 7:51 am

If I measure from R25 to R27 I get +18.3 and if I measure from R29 to R31 I get -18.8. I cross checked every component with a working A12 and everything is oriented correctly.
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Postby tpryan » Tue Mar 13, 2012 10:14 am

Then I guess we'll need to see it. Send an e-mail to rma@seventhcircleaudio.com for return instructions.
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Postby Matt... » Fri Mar 16, 2012 9:40 am

Problem solved. I had turned R25 and R29 clockwise instead of counter clockwise. Everything works now.
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