TB 9-6625-003-35
(3) INPUT SELECTOR switch to XTAL 200Ω.
(4) METER SCALE switch to NORMAL.
(5) Power (LINE) switch to ON.
16. Sensitivity, Stability, and Noise (Exempt AN/GSM-256)
a. Performance Check
(1) Connect equipment as shown in figure 3.
(2) Set ratio transformer (A6) controls to .100000.
(3) Adjust test oscillator (A9) frequency for 1 kHz and amplitude for an on-scale
indication.
(4) Adjust test oscillator frequency for a peak indication on TI meter and reduce
amplitude as necessary to maintain an on-scale indication.
(5) Adjust test oscillator amplitude for a 0-dB indication on TI meter.
Test
oscillator output meter will not exceed 1 V rms.
(6) Vary autotransformer output from 105 to 125 V ac and back to 115 V while
maintaining 0 dB indication on TI meter with test oscillator amplitude control. Test
oscillator output will not exceed 1 V rms.
(7) Adjust test oscillator amplitude to 0.03 V and record TI meter indication.
(8) Disconnect test oscillator and connect termination (B7) to TI INPUT.
(9) Set RANGE switch to 60. TI meter indication will be less than (down scale)
indication recorded in (7) above.
b. Adjustments. No adjustments can be made.
17. Bolometer Bias
a. Performance Check
(1) Set RANGE switch to 0 (zero).
(2) Adjust resistance standard (A7) to 200 ohms and connect to TI INPUT, using
cable (B4).
(3) Connect dc voltmeter (A4) to resistance standard, using cable (B5).
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