TB 9-4931-488-24
b. Adjustments
NOTE
Disconnect all equipment before proceeding.
(1) Position controls as listed in (a) through (h) below:
(a) COUNTER MODE pushbuttons as listed in 1 through 3 below:
1. EXPAND X10 and X100 released.
2. LOCK ON released.
3. INT pressed.
(b) FM k/MHz pushbutton pressed.
(c) PEAK DEVIATION switch to 2.56 MHz.
(d) FM control fully cw.
(e) RANGE MHz switch to 512 - 256.
(f) FREQUENCY TUNE control for FREQUENCY MHz display indication of 300 MHz.
(g) FM switch to DC.
(h) RF OFF/ON switch to ON.
(2) Connect multimeter INPUT HI to A5TP6 (BUFFER OUTPUT, fig. 3) and
INPUT LO to chassis ground. Adjust A5R23 (fig. 3) for a 0.000 0.0005 V dc multimeter
indication.
(3) Disconnect multimeter INPUT HI from A5TP6 (fig. 3) and connect to A5TP2
indication.
(4) Set FM switch to CAL. Disconnect multimeter INPUT HI from A5TP2 (fig. 3)
and connect INPUT HI to A5TP5 (BUFFER IN, fig. 3). Adjust A13R3 (FM CAL, fig. 3) for
a 1.000 0.001 V dc multimeter indication.
(5) Disconnect multimeter INPUT HI from A5TP5 (fig. 3) and connect to A7TP2
indication.
(6) Connect equipment as shown in figure 7.
(7) Position controls as listed in (a) through (j) below.
NOTE
Some of these TI control settings are repeated from the
performance check because of their importance to the
adjustment procedure.
(a) LEVEL VOLTS pushbutton pressed.
(b) AM switch to OFF.
(c) FM switch to INT.
(d) FM control fully ccw.
38
