TB 9-6625-1918-24
d. When indications specified in paragraphs 8 and 9 are not within tolerance, perform
the power supply check prior to making adjustments. After adjustments are made, repeat
paragraphs 8 and 9. 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.
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.
7. Equipment Setup
a. Position controls as listed in (1) through (5) below:
(1) BOLO TEMP COEF (COEF on TS-779/U) switch to NEG.
(2) BOLO RES (RES on TS-779/U) switch to 200.
(3) RANGE (POWER RANGE on some models) switch to 1.0 MW.
(4) BOLO BIAS CURRENT (BIAS CURRENT on TS-779/U) switch to OFF.
(5) ZERO SET COURSE and FINE controls fully ccw.
b. Remove TI cover and connect TI to autotransformer.
c. Connect thermistor mount (supplied with TI) to TI.
d. Connect autotransformer to a 115 V ac (volt alternating current) power source and
adjust for a 115 V ac output.
e. Set power switch to ON.
f. Energize equipment and allow at least 15 minutes for equipment to warm up and
stabilize.
8. Voltmeter Zero and Full Scale Circuits
a. Performance Check
(1) Connect multimeter to TI G (ground) (fig. 1) and CAL, connectors.
(2) Adjust ZERO SET COURSE, and FINE controls fully cw.
(3) Advance BOLO BIAS CURRENT (BIAS CURRENT on TS-779/U) switch until
TI meter pointer swings cw.