JLM AC/DC troubleshooting

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martthie_08
Posts: 12
Joined: Wed Jun 06, 2007 7:31 pm
Location: Stuttgart, Germany

JLM AC/DC troubleshooting

Post by martthie_08 »

ok, I need a little help troubleshooting my busted AC/DC powersupply. By stupid mistake I messed up the power transformer wiring and some caps went poof :oops: Now that the caps are replaced the 48V section is fully functional, but the voltages at the V+ and V- just sit there at unregulated DC voltage (21V with 15V PT), the trimpots don't change the voltage. How can I find out what's broken? It's not the regulators, I already replaced one of them... thanks for any help!!

martthie_08
Posts: 12
Joined: Wed Jun 06, 2007 7:31 pm
Location: Stuttgart, Germany

Post by martthie_08 »

again :oops: my bad, nothing was broken, I just had the trimpots turned fully clockwise, which gives maximum voltage - from there you have to give it a couple of turns counterclockwise before the regulator starts bringing the voltage down. Now got +/- 15V and 48V and everything is perfect.

Image

JLM AC/DC with new (big) caps - time to get this rats nest finished!!!
cheers, Marten

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