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Macintosh SE PSU 820-0385-A R309 Value
Posted by: unrealpower on 2023-06-26 20:29:06 I am trying to repair a 820-0385-A PSU. However, the casing for resistor R309 is gone and the resistor is a dead short. Does anyone know what the value of this resistor is? Also, what is the black mold-like corrosion on the bottom of the PCB?
Posted by: poyu_c on 2024-02-24 22:32:50 Sorry to resurrect an old thread... did you ever find out what value this is?
Posted by: dramirez on 2024-02-25 22:57:35 SE/30 Power Supply: Recap or ATX? Use the SONY CR-44 PSU as a frame of reference for the voltages and minimum Current output you will need: +5V: 6.0A +12V Sweep: 1.25A +12V Disk: 2.1A -12V: 0.5A Sweep and Disk are not isolated, so you could drive both with a single +12V power line rated at 3.35A or higher. And no, a -12V... 68kmla.org
Posted by: poyu_c on 2024-02-26 01:09:13 SE/30 Power Supply: Recap or ATX? Use the SONY CR-44 PSU as a frame of reference for the voltages and minimum Current output you will need: +5V: 6.0A +12V Sweep: 1.25A +12V Disk: 2.1A -12V: 0.5A Sweep and Disk are not isolated, so you could drive both with a single +12V power line rated at 3.35A or higher. And no, a -12V... 68kmla.org Thanks for the link, I saw this post but the answer wasn't definite. I just ordered the caps for them and was lucky enough to score a Sony power supply from eBay, probably end up using that anyway.
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