TB 9-6625-003-35
(3) Adjust test oscillator (A9) frequency for 1 kHz and amplitude for an on-scale
indication on TI meter.
maintaining an on-scale indication with GAIN control. Frequency counter (A5) will
indicate between 980 and 1020 Hz.
(5) Adjust GAIN control for 0-dB indication on TI meter 0 to 10 DB scale.
(6) Decrease test oscillator frequency until TI meter indicates 1.5 dB on 0 to 10 DB
scale. Record frequency counter indication.
(7) Increase test oscillator frequency until TI meter indicates 0 (zero) dB and then
drops to 1.5 dB. Record frequency counter indication. If the difference between the two
recorded values is not at least 50 Hz, perform b below.
b. Adjustments
(1) Adjust test oscillator for peak indication on TI meter.
(2) Adjust R22 (fig. 1) fully clockwise and adjust GAIN control with test oscillator
amplitude for a 0-dB indication on TI meter 0 to 10 DB scale.
(3) Adjust R22 until TI meter indicates 4 dB on 0 to 10 DB scale (R).
11. Range Accuracy (exempt AN/GSM-256)
a. Performance Check
(1) Adjust GAIN control fully clockwise.
Figure 3. Range accuracy-equipment setup.
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