Transmitter Frequency and Power

TB-9-6625-2163-35 Transponder Test Set TS-1809 (AN/APM-123(V)1) Manual
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TB 9-6625-2163

(7) Adjust variable attenuator until oscilloscope indication is 50 percent of that

recorded in (5) above. ACCEPT indicator will glow.

(8) Disconnect oscilloscope probe from TI and remove variable attenuator connected

between RTS MAIN RF I/O and circulator PORT 1.

b. Adjustments

(1) Adjust variable attenuator until oscilloscope indication is 70-80 percent of dc

voltage recorded in (5) above, and adjust TI test control A12R19 (fig. 2) until ACCEPT and

REJECT indicators glow alternately (R).

(2) Adjust variable attenuator until oscilloscope indication is 50 percent of dc

voltage recorded in (5) above. ACCEPT lamp will glow.

(3) Repeat steps a(4) through (7) above.

16. Transmitter Frequency and Power

a. Performance Check

(1) Set FUNCTION switch to FREQ/POWER.

(2) Turn power OFF and connect jumper between A4TP5 (fig. 2) and A13TP2 (fig.

2). Turn power ON.

NOTE

It may be necessary to allow TI to warm up for several minutes

after being turned off.

(3) Connect frequency counter input to PROBE connector and observe counter

indication. Display will read between 1029.794 and 1030.206 MHz.

(4) Disconnect frequency counter from PROBE connector and connect peak power

meter.

(5) Observe power meter indication and allow reading to stabilize. If power meter

indication is not between -5 and -7 dBm, perform b(1) below.

(6) Set power switch OFF and move jumper from A4TP5 (fig. 2) to A4TP4 (fig. 2).

Set power switch ON again.

(7) Observe power meter indication and allow reading to stabilize. If power meter

does not indicate between -20 and -22 dBm, perform b(2) and (3) below.

(9) Set power switch OFF and remove jumper from A4TP4 (fig. 2) and A13TP2 (fig.

2). Set power switch ON again.

(10) Set FUNCTION switch to SELF TEST and verify ACCEPT indicator is on.