Using a Digital Multimeter for the first time


After 15 years of service I replaced my old voltmeter with a Radio Shack Digital Multimeter.The instructions read that the amps should be turned off when inserting the leads. This would mean that after playing the amp for 2 hours I would have to turn them off insert the leads and then turn the amp back on.I doubt if I could get an accurate reading this way but Radio Shack says I could.So,I ask for your opinions.
Thanks all
oem
Jea48> Thank you for your advise.
Herman> This morning I warmed my amp for 30 minutes and with the amp on I inserted the leads from my voltmeter.I turned the meter on and the amp started to smoke.I shut everything off, removed the leads and let everything cool down.
I powered the amps back up and everything was fine.
I then followed the instructions of inserting the leads turning the meter on and then powering up the amps and left it that way for 30 minutes and then took the reading.This worked perfectly.
I agree with your method and have always biased that way.I have know idea why my new Radio Shack voltmeter operates differently.
Mr O- In my previous post I was stating the method that works for my Cary amps, not suggesting you try the same. There are too many variations on the bias adjusting theme to make generalities. Glad you found a method that works without the smoke issue!
when you smoked your amp, where you in voltage or current mode with your digital voltmeter?Did it have a bad smell? if it did, you should have your resistors checked out, if you find any smoked, replace it for it has increased in resistance which will effect that circuit in the long run.
W.>I was measuring bias using a DC VOLTS scale.
The resister is still reading the same as is noted in the owners manual.I thank you for this information.
Sorry you had trouble but the advice was correct.

I have made 10's of thousands of voltage measurements on live circuits with all types of analog and digital meters and never smoked anything. Properly used there is no way a digital meter set to volts could cause smoke. Impossible. The most logical explanation is you accidentally set it to measure current as you turned on the meter

You should have the meter on and then insert the leads.

You really should open it to inspect for damage and replace the part that smoked.