[Test-Equipment] Simpson 270 VOM

[Bill Abate]

Need help on the correct procedure for calibrating my 270.  It started 
with the ohms scale zero adjustment needing to be set at minimum 
resistance with the probes shorted to zero the meter. Batteries are 
fine.  The service info I have indicates there is no adjustment for 
resistance scales.  Traced out the circuit and all resistors are at the 
specified values.  Did a calibration on the 1 ma scale as  the R27 pot 
is in series with the basic movement. That did not help.  The only thing 
left to do is adjust the R32 pot that is across the basic movement.  I 
can't find any info on how to adjust that pot.  My best guess is to use 
it to calibrate the 50 micro amp scale but I'd like confirmation before 
trying that.  When I checked the 50 micro amp scale the specified 
current only showed 44 on the meter..

Thanks,


Bill Abate