NAVAIR 17—2OAX—737
4.5.3 Verify that the electronic counter indicates between 29.994 and 30.006 Hz.
4.5.4 Set the TI FREQUENCY MHz switches to 108.100, and the G/S DDM switch to 90 Hz.
4.5.5 Disconnect the electronic counter from the TI 30 Hz REF jack, and connect it to the TI rear panel
DEMOD jack.
4.5.6 Verify that the electronic counter indicates between 89.982 and 90.018 Hz.
4.5.7 Set the TI LOC—G/S frequency switch to G/S. Ensure that the TI frequency display indicates
334.700.
4.5.8 Verify that the electronic counter indicates between 89.982 and 90.018 Hz.
4.5.9 Set the TI G/S DDM switch to 150 Hz.
4.5.10 Verify that the electronic counter indicates between 149.97 and 150.03 Hz.
4.5.11 Set the TI LOC—G/S frequency switch to LOC.
4.5.12 Verify that the electronic counter indicates between 149.97 and 150.03 Hz.
4.5.13 Set the TI FREQUENCY MHz switches to 108.000.
4.5.14 Adjust the TI 30 Hz tone modulation control to UNCAL [fully ccw (0)].
4.5.15 Connect the oscilloscope vertical amplifier input to the TI rear panel TONES jack.
4.5.16 Set the oscilloscope controls for 500 mV vertical sensitivity, 100 i.ts/div sweep time, and the trigger
slope to positive
(+).
4.5.17 Adjust the oscilloscope trigger and position controls to vertically center the TI 9960 Hz signal on
the oscilloscope CRT display, and position the sweep trigger point at the left edge of the horizontal center
line. (See Figure 1.)
Figure 1. FM Deviation Display
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