The Power Supply-Reforming the Capacitors

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The first order of business is to get the power supply up and running again. The capacitors had to be reformed before anything else could happen. All of the large capacitors were removed and wired in parallel with a large bleed resistor.
They are drawing very little current from the power supply now and should be ready to go.

The 8μF 660V capacitor is actually an AC capacitor, which is two electrolytic capacitors back to back. So this one will need to be reversed and reformed again.

Micheal Thompson at Rhode Island Computer Museum was very helpful in explaining this process and the AC capacitor.


To do:
Once the capacitors are put back in the computer, we will power it on slowly with a variac. This will happen sometime in the coming week when we get the variac. The Maintenance Manual  volume II has a table with the output voltages and their tolerances that will be useful for testing. 

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