Norm Dresner wrote:


My point in checking for oscillations was that sometimes an oscillating Op
Amp can give some very strange readings on a simply DMM.

Norm


It is probably just a blown opamp, but I have also seen this behavior
on some manufacturers 741's when any input is forced to be higher than
1.2V from the + rail.

As a simple check, short the inv and non inv inputs of the opamp together,
and then:

a) check their voltage relative to the +supply. and
b) check the output voltage.

-Chuck Harris