TB 9-6625-1138-24
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.
d. When indications specified in paragraphs 8 through 12 are not within tolerance,
perform the power supply check prior to making adjustments. After adjustments are made,
repeat paragraphs 8 through 12. 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 check where applicable.
a. Remove protective cover from TI as required to gain access to test points and
adjustments.
b. If TI R.M.S. VOLTS meter does not indicate 0 (zero) on 0 to 1.0 scale, adjust meter
adjustment screw (located below meter face) until pointer indicates 0 (zero).
c. Set BATTERY-AC (DC-AC on some TI's) switch on rear of TI to AC.
d. Connect TI to autotransformer.
e. Position controls as listed in (1) through (9) below:
(1) POWER switch to ON (up).
(2) MODE SELECTOR switch to NORMAL.
(3) SCALE VALUE switch to ABSOLUTE.
(4) MAX INPUT VOLTAGE switch to 1.
(5) RANGE (VOLTS) switch to 30 mV.
(6) FREQUENCY dial to 0.0 kHz.
(7) OUTPUT AMPLITUDE control fully cw.
(8) ZERO SET control for maximum indication on TI R.M.S. VOLTS meter.
(9) CARRIER BAL RES and CAP adjustment screws for minimum indication (-40
dB or less) on TI R.M.S. VOLTS meter.
NOTE
RES and CAP adjustments interact.
Repeat (9) above as
necessary for best results.