■CALIBRATION & MAINTENANCE
■Measure and record the source power using the reference meter
■Transfer the same power level to the meter to be calibrated, set MAX/MIN to display power, then +/- to adjust the reading to match the noted reference reading. Note: The optical power is measured only when entering this mode. It is not continuously updated.
■Set MAX/MIN to read and note the new stored calibration offsets, and then SET to store and exit, or CANCEL to abandon and exit
■Go back and check the source power with the reference meter, to ensure source drift is within limits.
■When calibration is complete, remove the calibration shunt, and place an
■Do no forget to update your calibration records, and schedule the next due date.
N3970A
Maintenance
CAUTION! Do not open unless the warranty has expired, you are authorised to do so, and you have a static protected work station. Opening the unit will invalidate any warranty claim. There are no internal user adjustable components, fuses, or calibration features.
The optical sensor / connector assembly is not user serviceable.
Opening the instrument:
■Use static protected procedures
■Remove the batteries, and leave the battery cover open.
■Pull open the optical connector covers.
■Place the instrument face down on a soft mat, and undo the 6 screws in the rear housing.
■The instrument can now be gently pulled apart.
■The instrument will come into two halves joined by a ribbon cable. The optical section is located in the bottom half, with the microprocessor, supply, calibration constants and controls in the top half.
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