On Fri, 17 Sep 2004 15:58:23 GMT "Norm Dresner" wrote:

I have an HP200CD that needs some loving care. The manual says to measure
the difference in the voltage between two different points in the circuit --
it shouldn't be all that much but the voltages between these points and
ground is in the hundreds of volts range. The manual also says that I
should be using a meter with 220M ohm or greater input impedance to make the
voltage measurements. Any suggestions where such a beast could be
bought/rented/stolen?

There are such devices, but any modern DVM with a 10 MOhm input
impedance will work just fine to measure the voltages in your 200CD.
That warning is there because when the 200CD was made the common VOMs
of the day had much lower input impedances, so HP wanted to keep you
from using those.

I've worked on 200CDs with 10 MOhm meters with complete satisfaction.

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Jim Adney
Madison, WI 53711 USA
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