Author Topic: Scarred cap  (Read 217 times)

Online scorpio333

  • Audio Connoisseur
  • ****
  • Posts: 500
  • got mule?
Scarred cap
« on: April 01, 2018, 01:52:13 PM »
Any idea what causes this? It's a cap on a power supply board. While it looks like it could make contact with the aluminum fin, it's just an illusion. There's no way it could have bent over that far.


Offline Sir Thrift-a-Lot

  • Ready For Intervention!
  • ******
  • Posts: 2989
Re: Scarred cap
« Reply #1 on: April 01, 2018, 06:41:10 PM »
I don't know what caused it, but I know I would replace it.   My WAG is a manufacturing defect that didn't reveal itself until power or enough heat caused it to act up.

Online scorpio333

  • Audio Connoisseur
  • ****
  • Posts: 500
  • got mule?
Re: Scarred cap
« Reply #2 on: April 01, 2018, 08:13:16 PM »
The JD9 that cap is in has an audible hiss in it. Tried multiple different remedies - tubes, OP amps, rerouting wires, etc and so far nothing has tamed it. So I was in there looking real close and found that cap. Some suggest multiple caps and diodes be replaced in the power supply, I'll add that one to the list.

Offline OldiesButGoodies

  • Administrator
  • *****
  • Posts: 2478
  • Be nice, it is free!
Re: Scarred cap
« Reply #3 on: May 07, 2018, 01:11:54 PM »
The JD9 that cap is in has an audible hiss in it. Tried multiple different remedies - tubes, OP amps, rerouting wires, etc and so far nothing has tamed it. So I was in there looking real close and found that cap. Some suggest multiple caps and diodes be replaced in the power supply, I'll add that one to the list.

Scorpio - IMO you are overthinking this. "When I doubt, recap" - that is my motto. But seriously - why not remove the cap and test it?  For more than a basic test I acquired this thing from Amazon on the cheap:

https://www.amazon.com/Multifunction-transistor-Capacitor-Inductance-screwdriver/dp/B071Y5CHPK/ref=sr_1_7?ie=UTF8&qid=1525712694&sr=8-7&keywords=electronics+tester

Of course, I would rather have a Sencore cap analyzer like OCCD,  but this does well enough for $16, able to measure ESR etc. Also great if you have a bunch of similar caps built to a certain tolerance and wish to match several to lower tolerance for a left/right circuit recap.

OBG


Spkr: Harbeth 30.1 on Sound Anchor 4 post stands
Pre: Rogue 99 Magnum
Phono: VPI Aries 1,  Van de Hul Frog
CD: Oppo 203
Cass: Tascam 122MkII
R2R: Revox B77
Sub: