Steve, if this really is a "mil spec'd"
device I would say you really need to
get one of your EE's to buy-off on your
test methodology ... no offense to the
list, but this is like getting "medical
advice" from a panel over the internet ...

What if, during your "testing" of this particular
device or box, something shifts or changes such
that the RMS value reads within tolerances on
the Keithley - yet the actual value/waveform
has shifted considerably from the 800 Hz 50%
duty cycle square wave?

Depending on the box you're checking/testing, this
may not be an issue - perhaps this is a simple
functional check an LRU (Line Replaceable Unit)
of some other non-critical parameter and this
isn't an issue.


RF Jim

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