Discharging Pas quad cap

Before I do any work, what's the best way to discharge the quad cap and/or all caps?

Thanks

Have a multimeter ready, and a resistor 500-2000 ohm a little larger so it's convenient
to handle.

Then measure the voltage on the cap ( any of the + connections). With that value in mind
then replace the multimeter with your resistor, one lead to the cap one lead to ground
(any ground). Hold it for 10s, then repeat measurement. When you are down under 10V
you are safe to work.

Alternatives:
One could create a "boxed" resistor with clip-on cables for the purpose. Or one could equip all amps with a "bleeder" of some 100kohm that will discharge in a few minutes.

Thanks for your help! This sounds easy enough! About the ground. An unplugged Pas or ST70 chassis is fine? If not, what's the best way? Also, what setting on the multimeter?

poconoman wrote:Thanks for your help! This sounds easy enough! About the ground. An unplugged Pas or ST70 chassis is fine? If not, what's the best way? Also, what setting on the multimeter?

the chassis _is_ the ground, any metal part will do(providing you get contact).
You might be able to hear/observe a small flash when the resistor makes the first contact.

when using a auto-ranging multimeter then it's easy. Other wise use the range
applicable for the highest voltage you expect ( >300V DC )

I remember that i used an old Simpson where i had mounted 100kohm across the
leads, this was used solely to discharge caps at a workshop i worked in.That way
one had regular testpins to poke around with and at the same time could see the voltage
(falling ).

Had a hunch the chassis is good. Just wanted to make sure.

I guess I get the resister at Radio Shack?

Got a 1 meg at 1 / 2 watt. Good?

poconoman wrote:Got a 1 meg at 1 / 2 watt. Good?

one: it's physsically small ( your fingers will be close to cap voltage)
a 2w is larger and easier to grab without risking "zaps"

two: 1 mohm will draw 0.3mA, it will take ages to discharge
1kohm will draw 0.3A initially ans in a few seconds discharge
anywhere between 1k and 10k will do.

peterh wrote:

poconoman wrote:Got a 1 meg at 1 / 2 watt. Good?

one: it's physsically small ( your fingers will be close to cap voltage)
a 2w is larger and easier to grab without risking "zaps"

two: 1 mohm will draw 0.3mA, it will take ages to discharge
1kohm will draw 0.3A initially ans in a few seconds discharge
anywhere between 1k and 10k will do.

Ok, back to the shack. I have the receipt so I'm fine.

1K-10K at 2W. Got it.

peterh wrote:

poconoman wrote:Got a 1 meg at 1 / 2 watt. Good?

one: it's physsically small ( your fingers will be close to cap voltage)
a 2w is larger and easier to grab without risking "zaps"

two: 1 mohm will draw 0.3mA, it will take ages to discharge
1kohm will draw 0.3A initially ans in a few seconds discharge
anywhere between 1k and 10k will do.

I found some 3W at 5.6K. Good?

poconoman wrote:

peterh wrote:

poconoman wrote:Got a 1 meg at 1 / 2 watt. Good?

one: it's physsically small ( your fingers will be close to cap voltage)
a 2w is larger and easier to grab without risking "zaps"

two: 1 mohm will draw 0.3mA, it will take ages to discharge
1kohm will draw 0.3A initially ans in a few seconds discharge
anywhere between 1k and 10k will do.

I found some 3W at 5.6K. Good?

That's ok. Be careful!

Thanks for all your help! I'll be careful.

Another thought. Does it matter which lead on the resistor goes on the cap and the other on the ground?

poconoman wrote:Another thought. Does it matter which lead on the resistor goes on the cap and the other on the ground?

No. A resistor is "symmetric" and non-polarized.

Again, thank you. You've been fantastic!