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Old 01-11-2017, 12:10 PM
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mr_fixer mr_fixer is offline
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new transistor, no change in action. I have 30 volts on the hot which i think is the start up voltage, i have 320 in a different section, but don't know enough about this weird power supply.

Quote:
Originally Posted by Findm-Keepm View Post
I've got the service lit - most of it. I have the model specific data and the supplement with schematic, parts list, breakdown list and interchangeability data. I also have the Switchmode power Supply manual (theory, general operation, a must for the "bitch mode" supplies these have...) from NAP, all yours for postage. PM me your address, and I'll get it out to you.

In the meantime, do you have 130V across the diode (D404) on the yoke? Negative lead to the anode (hot ground...)That was always our starting point - D404 is a high-failure item in these chassis, and my earlier attachment provides a list of stuff to check as well - lots of bad solder jobs on the early runs of these chassis - the 25C55X series didn't seem to have the solder issues, just the earlier 25C53X and 25C54X stuff.

January 1986....when the Challenger tragedy struck.....
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