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Title: Selecting replacement caps Post by: wx3k on November 22, 2008, 11:14:28 AM I need to recap a receiver I have. It has a electrolytic can, 30/10/10 450v.......Of course finding an exact replacement is impossible. I was thinking of ordering a standard 3 section that is 30/30/30 at 525v.....Would this be a close choice ? Or would a 20/20/20 be better with a 10 uf cap paralleling one 20uf section be a better choice ?
Title: Re: Selecting replacement caps Post by: wx3k on November 22, 2008, 02:38:30 PM ??? No answers yet ? Is this an embarrassing question ? :-[
Title: Re: Selecting replacement caps Post by: KL7OF on November 22, 2008, 02:50:08 PM I have used higher value (MF) caps in filter applications with no ill effects...That 30/30/30/ at 525 volts would be my choice...good luck .....Steve
Title: Re: Selecting replacement caps Post by: WB2YGF on November 22, 2008, 08:24:20 PM How 'bout 20/10/10/10 µF @ 450 VDC and paralleling a 20 & a 10?
CAPACITOR, ELECTROLYTIC, 20/10/10/10 µF @ 450 VDC From: http://www.tubesandmore.com/ C-EC20-10-10-10 4 section electrolytic capacitor, used in Dynaco PAM-1 preamplifiers. 1-3/8" diameter x 2" tall -10% to 50% tolerance Three 10 µF sections, rated at 450 VDC, and one 20 µF section, also rated 450 VDC. This is not a standard design of FP cap as the 20 mfd is B(lank). Standard rolling would be D(iamond) as the high cap section. Title: Re: Selecting replacement caps Post by: wx3k on November 22, 2008, 09:47:45 PM Good idea ;D
How 'bout 20/10/10/10 µF @ 450 VDC and paralleling a 20 & a 10? CAPACITOR, ELECTROLYTIC, 20/10/10/10 µF @ 450 VDC From: http://www.tubesandmore.com/ C-EC20-10-10-10 4 section electrolytic capacitor, used in Dynaco PAM-1 preamplifiers. 1-3/8" diameter x 2" tall -10% to 50% tolerance Three 10 µF sections, rated at 450 VDC, and one 20 µF section, also rated 450 VDC. This is not a standard design of FP cap as the 20 mfd is B(lank). Standard rolling would be D(iamond) as the high cap section. Title: Re: Selecting replacement caps Post by: w3jn on November 23, 2008, 08:11:09 AM Or you can rebuild the can using discrete components.
Circumcise the can using a moto-tool with a cutoff wheel; the least noticible place is at the base of the crimp. Pull out the guts, install new caps (hopefully the ones you've bought will fit in the old can), make sure the leads are insulated so they don't short to each other and/or the can, and glue back together with JB Weld. Title: Re: Selecting replacement caps Post by: wx3k on November 23, 2008, 09:25:00 AM Cute pic of your pooch ! lol
This is another idea. Is there any toxic chemical considerations when dealing with the innards of a cap ? I think I found a "NEW" can of exact dimensions and value at Antique Electronics Supply. Or you can rebuild the can using discrete components. Circumcise the can using a moto-tool with a cutoff wheel; the least noticible place is at the base of the crimp. Pull out the guts, install new caps (hopefully the ones you've bought will fit in the old can), make sure the leads are insulated so they don't short to each other and/or the can, and glue back together with JB Weld. Title: Re: Selecting replacement caps Post by: WB2YGF on November 24, 2008, 11:07:20 AM Is there any toxic chemical considerations when dealing with the innards of a cap ? Just pretend it's 1965 when we didn't worry about that stuff. :)Title: Re: Selecting replacement caps Post by: W1EUJ on November 24, 2008, 11:11:22 AM Yes - do not take internally. That's all. Now shut yer yap and yank the guts out of that cap!
I use a pipe cutter, it is clean if done right, and the groove it pushes in leaves space for a fillet of JB Weld, hot glue, etc. Title: Re: Selecting replacement caps Post by: ab3al on November 26, 2008, 07:14:11 AM dont you dare.... im calling the epa AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
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