Re: AC noise on DC effect stepper drivers?

In a message dated 7/14/99 12:09:19 PM Pacific Daylight Time,
jmelson@... writes:

<< By the way, some old Simpson VOMs will
read DC on the AC scale, unless you switch in the DC blocking
capacitor, which I think is cryptically marked 'Output' on the
polarity switch. >>

The reason for the DC reading on the AC scale is that the DC is being fed
thru one side of the rectifier.
The OUTPUT function was designed to block the DC with a capacitor, and allow
the AC thru. One use of the OUTPUT function was on the plate of a tube,
block the DC, and read the output AC voltage.
When you use an oscilloscope on AC function, you are doing the same thing,
using a capacitor to block the DC voltage.
bill