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Projectone Mark ivb need help

Maddart

Maddart

Active Member
Just picked up a mark ivb (Free) and plugged into my DBT and it powers up, relay clicks although it looks like the contacts are smoked. Haven't hooked up to speakers at this point. Of coarse there are no schematics available but it seems power supply voltages are off. I will post those voltages after i triple check them.IMG_8759.jpg
 
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Here is what i have gathered so far. Rectifier pin 5 9v seems a bit concerning. The rest looks normal. I will be documenting for other that might need this info as there is no info available at this point. I will do my best. I hope some vintage audio gurus can chime in and help me along the way. Its been a good 15 years since i have worked on any audio gear. Markthefixer was a big help to me back then. Here is what i have so far. The unit turns on, DBT 100w bulb goes off completely after a couple of seconds. I have found a few leaky capacitors ( I will post Cap lists per PCB as i go along). the protection relay does click however in its current condition i will be replacing.
Rect. PCB.jpgPower supply PCB.jpgIMG_8740.jpg
 
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