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Hello, I have a Macintosh Plus that have 2 problem: The Analog board only provide 9.4V measured on the connector on the Analog board side (Same on the J8 from the Logic board). All the connector have been soldered (with new solder past). The board had bad corrosion traces but I did measured all connection with an ohmmeter and they all seems to be fine -> I will probably need to change the 12V 5W Zener diode to solve the first issue. (I guess). I know that the Analog board has an issue because I tested it with a known good logic board and I had the same issue (9.4V instead of the 12V) The logic board was cleaned and the ROM and RAM where re-seated. When testing the logic board with a known working Analog board, the Macintosh Plus will reboot rapidly in a loop. The screen is not even able to show a good icon, only try to show a partial image. To be safe I removed the Programmer and Logic switch to check it wasn't due to a reset being inserted by the bad contact on these switch. I check on the Dead Mac Scroll but I wasn't able to seen a similar issue. Power line on the logic board aren’t shorted... however on a good logic board I was able to measure ~150 ohm between +5V and GND, while on the "bad" logic board I only had ~70ohm Anybody had an idea on how I should proceed? I do have a working unit to compare and test parts... Thanks in advance