Discharging caps

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fabiomayo
Posts: 233
Joined: Mon Apr 24, 2006 1:40 pm
Location: Niteroi, RJ - Brasil

Discharging caps

Post by fabiomayo »

I guess I shouldn't be asking this at this point in life :lol:

Anyway, I've been discharging my caps through the preamp (pin 2
if I remember correctly with no resistor whatsoever). So far, I'm
alive and well. I'd like to keep that way, so I figured I should put
together one of those discharging fixtures as the ones described
here:
http://www.repairfaq.org/sam/captest.htm
http://www.schematicheaven.com/mods/capdischarge.htm

All I have handy (kinda difficult to find parts where I live) is 470R
and 910R 5w cement power resistors. Would this do the job?
I figured I could either use the 470R/5W or two in parallel to get
a smaller resistance and better power handling...

What do you think?
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skyboltone
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Location: Sparks, NV, where nowhere looks like home.

Re: Discharging caps

Post by skyboltone »

Fabio;
I personally don't see the point of the high power low value resistors. The power rating of a resistor is for heat dissipation during use. The drain down resistor will perform all of it's work rather quickly. Long before it has a chance to heat up. I use a 1/2watt 3.3K resistor on about a 18" lead with an alligator clip on the other end. Bend a little hook in the resistor lead and hook it around your last power supply section lead wire after the unit has been de-energised. Give it about 20 seconds, then clip a direct grounded lead at the same point and leave it there while you work.

Don't forget to lift your ground before turning it back on.
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Bob-I
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Location: Hillsborough NJ

Re: Discharging caps

Post by Bob-I »

I use a 2.2K 2W on 6" long leads with aligator clips. Works fine. Almost any value will do, this was just handy.
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fabiomayo
Posts: 233
Joined: Mon Apr 24, 2006 1:40 pm
Location: Niteroi, RJ - Brasil

Re: Discharging caps

Post by fabiomayo »

Thanks, guys.

I had no idea on the power handling...

I have some aligator clips around here, I'll just solder them.

Thank you very much!
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