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I’m looking for a replacement capacitor in an A/C transformer secondary circuit. 4,000uf 50vdc bipolar radial.
This is the least expensive option I could find.
This capacitor is in an A/C circuit. Not D/C . I’ve read that electrolytic capacitors can’t survive in an A/C circuit. This has been the hard part of my search.
From your description I assumed this was the exceptionally common application of a transformer secondary circuit in a DC output power supply.
I don’t see any 4,000uf 50v
dcAC bipolar radial capacitors from any of my usual vendor sites.
What’s the application?
Knowing that application may help me remember a specialty capacitor supplier.
I’m repairing on old Heathkit turntable/radio receiver from the 1960’s for a friend.
All the old 60s audio gear I’ve worked on had diodes between the transformer and the capacitor, making it pulsed DC on the capacitors. The capacitors filter the pulsed DC into steady DC. Those circuits used polarized capacitors like these:
This particular model has the capacitor before the rectification. I’m assuming it’s there to reduce 60 cycle hum.
AFAIK, all a 4000uF capacitor in that position can do is generate heat, and possibly explode, it can’t alter the frequency of the AC power. It would also mean there are large uF value capacitors after the rectifiers to smooth the pulsed DC into steady DC.
In an AC to DC power circuit the only use for capacitors across the AC side is to reduce high frequency noise that comes along with the power source. For that application capacitors in the pF or nF ranges are used, and those are commonly available with AC voltage ratings and prices below $1.00US.
Can you show us the schematic diagram of the circuits?
I’m pretty certain you’ll find you are misreading the schematic which is very easy to do,