ESR test for tube amps ?

[stonedeaf]

Does anyone make a ESR meter that won't flame and die on a typical tube power supply cap (say 500 to 600Volts ?) I understand that the older units are still out there - but would be more interested in something recently manufactured.

[trobbins]

One expensive option is use a digital CRO with single event trigger and AC couple. Then switch a load resistance on to charged cap and check captured waveform to determine initial sharp voltage drop Vd = I x ESR. Where I is calculated from VDC and resistance.

You might flame the test circuit if not careful ;-)

Ciao, Tim

[singa]

Originally Posted by stonedeaf

Does anyone make a ESR meter that won't flame and die on a typical tube power supply cap (say 500 to 600Volts ?) I understand that the older units are still out there - but would be more interested in something recently manufactured.

Hi, The correct procedure is to discharge the cap to be measured first.

However there are old esr meter that have built in discharge circuit
like sencore. singa

[Doz]

Originally Posted by singa

Hi, The correct procedure is to discharge the cap to be measured first.

However there are old esr meter that have built in discharge circuit
like sencore. singa

... and preferably disconnect, so you don't measure the resistance of anything else there too ...