[sdiy] PSU ripple/hum testing

[Lincoln Fong]

Good to be back after a long period of silence.

Does anyone have a good way of testing for PSU ripple? I have some PSUs
(11 of them!) that can deliver 10 amps at +/- 15V and 30 amps at 5V. The
ripple under load is meant to be less than about 200 uV but my (not very
good) scope only goes down to 10mV per division. I was thinking I could
maybe build a small amplifier with DC input filter and 'listen' to the
ripple, maybe with a few calibrated LEDs as I would like to be able to
'poke around' inside my huge old mixing board and PSU rack. The initial
spike when attaching the probe could kill my amp/speaker/ears though.
Any ideas or should I get a better scope?

Thanks,

Lincoln

_________________________
Lincoln Fong
http://www.fongelectronic.com