TB 9-4920-456-24
(4) Adjust R10 (located on right side of chassis) for a measuring receiver indication
between -18.0 and -21.0 dB.
(5) Disconnect signal generator 50 Ω coaxial cable from TI BOT ANT and reconnect
cable to TOP ANT. Adjust R10 (located on right side of chassis) for a measuring receiver
indication between -18.0 and -21.0 dB.
(6) Disconnect signal generator 50 Ω coaxial cable from TI TOP ANT and reconnect
cable to TI BOT ANT and repeat steps (3) through (5) above for best compromise.
(7) If b (1) through (5) indications above are within tolerance, post new values for
BOT 137 and TOP 137 on TI calibration label (located near REPLY ATTEN switch).
(8) Record new values of BOT 305 and TOP 305 recorded in a (14) and (20) above on
TI calibration label (located near REPLY ATTEN switch).
15. Cable Insertion Loss Test
a. Performance Check
(1) In TI transit cover, remove two W4 cables and one W5 cable from storage
compartment.
(2) On measuring receiver deselect RATIO function.
(3) Disconnect measuring receiver sensor module from TI RF and connect sensor
module to signal generator RF OUTPUT, using N and BNC connector adapters.
(4) On signal generator turn RF OUTPUT on.
(5) Setup measuring receiver for Tuned RF Level.
(6) On measuring receiver select RATIO function.
(7) On signal generator turn RF OUTPUT off.
(8) Connect one end of W4 cable to signal generator RF OUTPUT and connect the
other end of W4 cable to measuring receiver sensor module, using (TNC to BNC) connector
adapter.
NOTE
TNC to BNC adapter is supplied with AN/UPM 155 connector
box.
(9) On signal generator turn RF OUTPUT on.
