FINISHED THE RANGE ATTENUATOR WIRING AND PART NUMBERING
The numbers for the resistors were completely changed from the version in the manual, but they were mostly in the same arrangement. The values were changed a bit, with my version using standard resistance values while the newer version in the schematic took advantage of more diversity in values available later on.
ONE MAJOR QUESTION REMAINS TO BE ANSWERED
The version in the manual uses a constant current source produced by a transistor in the power supply to develop a voltage drop across resistors being tested by the meter. I don't know where my version gets the voltage to deliver to the resistors under test, as I don't see zener diodes, transistors or other parts that would act as a constant current source. I will have to trace out the wire from the function switch section C wiper as that is where the supply for resistance testing is delivered.
THE SCHEMATIC IS ESSENTIALLY COMPLETE EXCEPT FOR THE QUESTION ABOVE
I HAVE WHAT I NEED TO TEST, RESTORE AND CALIBRATE
Since I know the circuit design, parts numbers and test points for my version, I can use the calibration and diagnostic methods from the manual to get this meter in perfect shape.
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