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Filters
4/17/2006 9:39:01 PMJohn
I got a Grigsby-Grunow (Majestic 20) and want to replace the filter caps. It shows two 2ufd and some 1ufd caps and I wonder if I can replace them with 10ufd and/or 4.7ufd?
4/17/2006 9:46:53 PMNorm Leal
Hi John

I use 10mf @ 450 volts to replace original 1 & 2 mf filter caps. When these radios were made electrolytic caps weren't common. Later radios used 10mf in the same circuits. B+ voltage will be a little higher as larger caps hold voltage up better.

No need for the .07mf across the choke. If this cap isn't very close in value hum will increase. It was used as a tuned circuit to remove ripple since they didn't have large enough filter caps.

Norm

:I got a Grigsby-Grunow (Majestic 20) and want to replace the filter caps. It shows two 2ufd and some 1ufd caps and I wonder if I can replace them with 10ufd and/or 4.7ufd?

4/17/2006 11:34:08 PMJohn
Thanks Norm as I have plenty of 10's on hand and will now use them.

:Hi John
:
: I use 10mf @ 450 volts to replace original 1 & 2 mf filter caps. When these radios were made electrolytic caps weren't common. Later radios used 10mf in the same circuits. B+ voltage will be a little higher as larger caps hold voltage up better.
:
: No need for the .07mf across the choke. If this cap isn't very close in value hum will increase. It was used as a tuned circuit to remove ripple since they didn't have large enough filter caps.
:
:Norm
:
::I got a Grigsby-Grunow (Majestic 20) and want to replace the filter caps. It shows two 2ufd and some 1ufd caps and I wonder if I can replace them with 10ufd and/or 4.7ufd?



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