[Test-Equipment] Ohmmeter AN/PSM-43 (Ohmmeter ZM-21D/U)

[James Duffer]

I have a NOS AN/PSM-43 without a manual.  I realize this is used to test 
insulation resistance but I would like to know what test voltage is (I guess 
this depends on the rate the crank is turned, but what is the maximum 
nominal voltage?)  What is the meter scale, is it megohms?

Thanks for any information that can be provided.

73, Jim, wd4air