TB 9-6625-2151-24
Table 6. Transmitter Flatness at -40 dBm
Test instrument
right display
(mV ac)
indications
Min
Max
20 Hz
6.90
8.69
10 kHz
7.57
7.93
60 kHz
7.31
8.20
85 kHz
7.31
8.20
b. Adjustments. No adjustments can be made.
a. Performance Check
(1) Connect calibrator OUTPUT HI and LO to TI left TRMT/ RCV 310.
(2) Press pushbuttons and keys as listed in (a) through (d) below:
DISPLAY key to select RCV.
(a)
REV pushbutton.
(b)
SET UP RCV 600 pushbutton.
(c)
MEASUREMENT MEAS key to select NOISE.
(d)
(3) Set calibrator for a 0 dBm, 300 Hz output.
(4) Press FILTER FILTER key to select C-MESSAGE. TI left display will indicate
between 73 and 74 dBm.
(5) Repeat technique of (3) and (4) above at each frequency listed for C-MESSAGE
column of table 7. TI will indicate within limits specified.
(6) Repeat technique of (3) and (4) above for TI filter selections using appropriate
column and calibrator frequency settings listed in table 7. If TI left display indications are
not within limits specified, perform b below.
b. Adjustments
(1) Press calibrator RESET key and disconnect from TI.
(2) Connect left TRMT/RCV 310 to right RCV/TRMT 310.
(3) Press DISPLAY key to select TRMT and MEASUREMENT MEAS key to
(4) Press , STEP UP, STEP DOWN, and
keys until TI right display indicates
995 Hz. Adjust OUTPUT LEVEL control until left display indicates 0.0 dBm.
(5) Press DISPLAY key to select RCV.
(6) Move shorting bars on JU5 (fig. 1) to right (shorting pins 5 to 12, 6 to 11, 7 to 10,
and 8 to 9).
(7) Connect oscilloscope CHAN 1 to pin 1 of JU5 (fig. 1).
(8) Adjust R102 (fig. 1) for minimum ac signal on oscilloscope (R).