TB 9-6680-284-35
Manufacturer and model
Common name
Minimum use specifications
(part number)
AUTOTRANSFORMER
Range: 105 to 125 V ac
General Radio, Type W10MT3AS3
(7910809) or Ridge, Model 9020A (9020A),
Accuracy: 1%
or Ridge, Model 9020F (9020F)
FREQUENCY COUNTER Range: 2.3 to 551 ms period Fluke, Model PM6681/656 (PM6681/656)
Accuracy: 0.25% (period)
6. Preliminary Instructions
process. Personnel should become familiar with the entire bulletin before beginning the
calibration.
b. Items of equipment used in this procedure are referenced within the text by common
name as listed in table 2.
c. Unless otherwise specified, verify the result of each test and, whenever the test
requirement is not met, take corrective action before continuing with the calibration.
Adjustments required to calibrate the TI are included in this procedure. Additional
maintenance information is contained in the manufacturer's manual for this TI.
d. Unless otherwise specified, all controls and control settings refer to the TI.
7. Equipment Setup
WARNING
HIGH VOLTAGE is used or exposed during the performance of
this calibration.
DEATH ON CONTACT may result if
personnel fail to observe safety precautions.
REDUCE
OUTPUT(S) to minimum after each step within the
performance check where applicable.
b. Connect TI to autotransformer.
c. Set TI POWER switch to ON and allow 15 minutes for equipment to warm-up and
stabilize.
d. Set range function control to 670-4170 and adjust RPM control to 3600.
e. Adjust HIGH CAL trimmer until CAL indicator is either on or off (not blinking).
f. Adjust RPM control to 900.
g. Adjust LOW CAL trimmer until CAL indicator is either on or off.
