Uploaded December 2020 | Updated September 2026, 3 weeks ago

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This video describes the function of each calibration adjustment on the Simpson 260 volt-ohm-milliammeter. I also describe (at the end) a 50uA current source (using a Wilson current mirror) I put together to make the initial adjustments on the 260 easier. I don't show the 10A current shunt adjustment because I don't have a good 10A source to use. Please note that I am not a Metrology or Calibration professional, and don't have any traceable standards. The purpose here is to show what each adjustment does.
My notes for this video are here:
qsl.net/w2aew/youtube/Simpson260cal.pdf
Here are good 260 resource pages:
simpson260.com
simpson260.com/downloads/downloads.htm
Good "Theory of Operation" for the 260:
simpson260.com/downloads/simpson_260-6p_theory_of_operation.pdf
Sears repair manual for the 260:
simpson260.com/downloads/simpson_260-3_to_6_repair_instructions.pdf