Recapped My Predicta Tandem, I don't know what to do
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Joined: Dec 2008
City: Chicago, IL
I recall that in one of my Tandems all my voltages were also low but the set worked fine so I just let it go. As you mentioned, I typically pull the boards out and do a total rebuild since these are difficult sets to troubleshoot.
The voltage doubler uses the two capacitors to build up charge that gets added together to create B+. If the capacitance is too low to meet the load, B+ will drop. Likewise, if the internal resistance (ESR) of the cap is high, B+ will drop.
A simple thing to try is tack a capacitor in parallel with C1 and C2 and see if it brings B+ up.
Also, can measure the total current draw of the set? It should be 170 watts or 1.65 Amps according to Sams.
Messages In This Thread
RE: Recapped My Predicta Tandem, I don't know what to do - by Bob Andersen - 01-08-2022, 04:07 PM
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