[Amps] Alpha Ip problem

[Robert Kirkland]

The Alpha 76 indicates plate current by converting an 0-1 ma. old 1000 ohm 
iron vane meter to a volt meter and measuring the voltage drop through a 
series resistor. The volt meter circuit has an adjustable pot. You would 
think it could be calibrated, power off, with an ohm meter and work ok, 
1ma=1000 ohms per volt. It didn't work, does anyone know how this circuit is 
calibrated or how ETO set it up. I can make it work but would like to 
restore it properly, tnx.
Bob, w5pvr