TB 9-4931-488-24
(e) MODULATION FREQUENCY RANGE switch to FIXED FREQ 1 kHz.
(f) PEAK DEVIATION switch to 320 kHz.
(g) RANGE MHz switch to 64 - 32.
(h) FREQUENCY TUNE control for FREQUENCY MHz display indication of 50 MHz.
(i) OUTPUT LEVEL switch to +10 dBm (10 dB switch to +10 and 1 dB switch
to 0 for option 004).
(j) OUTPUT LEVEL vernier control(s) fully cw.
(8) Set measuring receiver to measure frequency.
(9) After measuring receiver acquires the frequency set pulse generator for 1 kHz
1.414 V rms output level.
(10) Set measuring receiver to MEASURE, More, Modulation Rate. When the
modulation frequency is displayed set to FM deviation with a 50 Hz high-pass and 15 kHz
low-pass filter.
(11) Adjust FM control for a 320 kHz measuring receiver indication.
(12) Adjust POS SHAPE, A7R12 and NEG SHAPE, A7R41 (fig. 3) for minimum
distortion indication (< 3%) on measuring receiver.
(13) Adjust FREQUENCY TUNE control slowly from 32 to 64 MHz while observing
measuring receiver. If measuring receiver does not indicate ≤ 3%, repeat technique of (11)
and (12) above while adjusting for best in tolerance condition across the band.
(14) Position controls as listed in (a) through (d) below.
(a) FM switch to AC.
(b) PEAK DEVIATION switch to 80 kHz.
(c) FM control fully cw.
(d) FREQUENCY TUNE control for FREQUENCY MHz display indication of 50 MHz.
(15) After measuring receiver acquires the frequency, set pulse generator for 1 kHz
with 0.707 V rms output level.
(16) Set measuring receiver for FM deviation with 50 Hz high-pass and 15 kHz low-
pass filter.
(17) Adjust R3 (MID, fig. 3) for an 80.0 0.1 kHz measuring receiver indication.
(18) Adjust FREQUENCY TUNE control for FREQUENCY MHz display indication
of 32 MHz. Adjust R2 (LOW, fig. 3) for an 80.0 0.1 kHz measuring receiver indication.
(19) Adjust FREQUENCY TUNE control for FREQUENCY MHz display indication
of 64 MHz. Adjust R4 (HIGH, fig. 3) for an 80.0 0.1 kHz measuring receiver indication.
(20) Adjust FREQUENCY TUNE control for FREQUENCY MHz display indication
of 50 MHz and repeat technique of (15) through (18) above until measuring receiver FM
deviation indication is 80.0 0.2 kHz at 32, 50, and 64 MHz.
(21) Set FM and RF OFF/ON switches to OFF and repeat paragraph 18 a above.
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