I am building the N. Pass A75 and I have run into a snag. As Nelson suggested I tested the reg. supply and I am getting a steady 50v.
The problem is when I put in the fuses for the unregulated suppy. I get ~44v DC which is what I would expect, but then he says to measure the AC. When I measure the AC across one of the cap using a VOM set on AC I get about 100v!
What could I have possible done wrong? it is such a simple circuit.
I am using a 31v tranny which I doulble checked is wired up correctly. I bought some 30000uf caps surplus they are marked McKintosh, they look good, but I have no way that I know how to test them, other than that the rectifiers are new from digikey. I have also placed bleed resitors across the caps to bleed them down when not in use.
The tranny buzzes for a fration of a secound, as it charges up the caps. Then I get the ac. When I turn it off the caps then beed off through their resistors.
I don't have a clue unless the caps are bad?
ANyone had any experience like this?
TIA
Greg
The problem is when I put in the fuses for the unregulated suppy. I get ~44v DC which is what I would expect, but then he says to measure the AC. When I measure the AC across one of the cap using a VOM set on AC I get about 100v!
What could I have possible done wrong? it is such a simple circuit.
I am using a 31v tranny which I doulble checked is wired up correctly. I bought some 30000uf caps surplus they are marked McKintosh, they look good, but I have no way that I know how to test them, other than that the rectifiers are new from digikey. I have also placed bleed resitors across the caps to bleed them down when not in use.
The tranny buzzes for a fration of a secound, as it charges up the caps. Then I get the ac. When I turn it off the caps then beed off through their resistors.
I don't have a clue unless the caps are bad?
ANyone had any experience like this?
TIA
Greg
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