Sensitivity, Stability and Noise

TB 9-4931-321-35

(3) Set TI INPUT (INPUT SELECTOR) switch to LOW.

b. Adjustments. Adjust A3R54 (R354 or R54) (fig. 1) until all multimeter indications

listed in table 4 are within specified limits.

Figure 1. Standing wave ratio meter - left view.

9. Sensitivity, Stability and Noise

a. Performance Check

(1) Connect function/arbitrary generator to TI INPUT using 50 Ω termination.

(2) Set function/arbitrary generator frequency to 1000 Hz and adjust amplitude for

up-scale indication on TI meter.

(3) Adjust FREQ control for maximum meter indication. If necessary, reduce

amplitude of function/arbitrary generator output.

(4) Adjust amplitude of function/arbitrary generator output for a 0 (zero) dB

indication on TI meter 0 (zero) to 10 dB scale.

(5) Function/arbitrary generator output will not exceed 0.15 V rms.

(6) Adjust autotransformer from 105 to 125 V, while maintaining 0 (zero) dB

indication on TI meter with amplitude control of function/arbitrary generator.

(7) Function/arbitrary generator output amplitude will not exceed 0.15 V rms.

(8) Adjust autotransformer for a 115 V output.

(9) Set INPUT (INPUT SELECTOR) switch to HIGH.