Acceptable Ripple

[Robert Jarratt]

Just checking a PSU in a MicroVAX 3100 Model 80. I am measuring about 10mV
ripple on the 5V supply and 20mV ripple on the 12V supply. Does that seem
reasonable?

 

I am not sure if it is a scope artefact, but there appear to be large spikes
at the top and bottom of each sawtooth. The machine appears to partially
work, it seems to be getting some errors during the memory test, but I don't
know if that is the spikes I am seeing or just a bad component somewhere.

 

Regards

 

Rob