TB 9-6625-2170-24
(12) Decrease calibrator frequency until TI indicates -3.0 dB. Calibrator frequency
will be between 28.5 and 31.5 kHz.
(13) Release FILTERS 30 kHz LO PASS pushbutton and press FILTERS A WTG
pushbutton.
(14) Set calibrator frequency to 100 Hz. TI will indicate between -18.1 and -20.1 dB.
(15) Set calibrator frequency to 1 kHz. TI will indicate between -1 and +1 dB.
(16) Set calibrator frequency to 10 kHz. TI will indicate between -6.5 and -0.5 dB.
b. Adjustments. No adjustments can be made.
12. Residual Noise
a. Performance Check
(1) Position controls as listed in (a) through (g) below:
(a) INPUT RANGE switch to AUTO RANGE.
(b) FUNCTION VOLTS pushbutton pressed.
(c) FUNCTION LEVEL pushbutton pressed.
(d) RESPONSE RMS/AVG pushbutton pressed to RMS.
(e) FILTERS 400 Hz HI PASS pushbutton pressed.
(f) FILTERS 80 kHz LO PASS pushbutton pressed.
(g) FILTERS 30 kHz LO PASS and A WTG pushbuttons released.
(2) Short TI INPUT + and using a good quality short. TI indication will be d 3.0 PV.
(3) Release FILTERS 400 Hz HI PASS and 80 kHz LO PASS pushbuttons and
press FILTERS A WTG pushbutton. TI indication will be d 1.5 PV.
b. Adjustments. No adjustments can be made.
13. Distortion Measurement Accuracy
a. Performance Check
(1) Connect equipment as shown in figure 4.
TI
SIGNAL
OUTPUT
CALIBRATOR
HI
INPUT
NPUT
I
+
OUTPUT
OUTPUT
LO
Figure 4. Distortion - equipment setup.
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