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[AMPS] Noises in electrolytic capacitors

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Subject: [AMPS] Noises in electrolytic capacitors
From: (Tom Rauch)
Date: Fri, 28 Sep 2001 10:27:30 -0400
> Anyway, I plan to pull all the caps this weekend and check the
> resistors. I hate to got to a smaller wattage, higher resistance
> design even though I did that successfully in my SB200, which clearly
> showed signs of heat damage to the caps. The bakelite (or similar)
> board with the caps and equalizing resistors is nicely done and a
> retrofit would be a jury rig. They use solder lugs and nicely dressed
> solid wire for the interconnections, one of which was never soldered
> (which I only discovered when I pulled this apart for repair.)

Just don't fall into the trap that one person does, and say that all 
high-power bleeders or equalizers are "bad" and replace them.

The resistor does not make the capacitor heat up, unless the 
ventilation is poorly planned around the resistor. The correct cure 
would be to improve ventilation or move the resistors further 
away...not to use insufficient resistance as one person always 

It sounds like your Henry is OK in that regard. Just check them 
and be sure they are within tolerance. The only drawback of a wire 
wound resistor is any slight nick or scrape (such as bumping the 
resistor with a screwdriver can open a wire inside the resistor if it is 
a high resistance resistor (wound with many turns of small wire).

If you do NOT have one or more off-value resistors (or a capacitor in 
backwards), then you have a bad capacitor. I have receiver batches 
of capacitors that were incorrectly manufactured. 

By the way, if it made muted "popping" noises now you might need 
to change the capacitors again because that noise (when it comes 
from a capacitor)  is when the dielectric inside a capacitor punches 
a hole in the insulating oxide.

73, Tom W8JI 

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