TB 9-6625-1999-35
CALIBRATION PROCESS FOR AN/GRM-50 (SG-479/U)
6. Preliminary Instructions
process. Personnel should become familiar with the applicable sections 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.
perform the power supply check prior to making adjustments. After adjustments are made,
repeat paragraphs 8 through 15. Do not perform power supply check if all other
parameters are within tolerance.
e. Unless otherwise specified, all controls and control settings refer to the TI.
7. Equipment Setup
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 checks where applicable.
a. Remove protective cover from TI only when necessary to make adjustments. Replace
cover after completing the adjustments.
115 V ac output.
d. Set POWER switch to ON and allow at least 20 minutes for equipment to warm-up
and stabilize.
e. Set POWER switch to off (down) and wait 30 seconds.
f. If necessary, adjust mechanical zero adjust screws for a zero indication on R.M.S.
VOLTS and PERCENT MODULATION meters.
g. Set POWER switch to ON and allow 2 hours for equipment to warm-up and stabilize.
