TB 9-6625-2009-24
15. Input Attenuator
a. Performance Check
(1) Position controls as listed in (a) through (d) below:
(a) AMPLITUDE MODE LINEAR pushbutton pressed.
(b) AMPLITUDE REF LEVEL switch to -30 dB.
(c) INPUT SENSITIVITY switch (white marker) to 1 V.
(d) RESOLUTION BANDWIDTH DISPLAY SMOOTHING switch to MIN.
(2) Adjust calibrator frequency to 10 kHz at 1 V output amplitude.
(3) Position controls as listed in (a) through (c) below:
(a) SWEEP MODE MANUAL VERNIER control for a peak indication.
(b) CAL 10 kHz control for a full scale display.
(c) DISPLAY CLEAR WRITE pushbutton pressed momentarily.
(4) Set INPUT SENSITIVITY switch and adjust calibrator output amplitude to
settings listed in table 9. Display will indicate within limited specified.
Table 9. Input Attenuator
Test instrument
Calibrator output amplitude
INPUT SENSITIVITY
Display indications (cm)
values (dBm)
switch settings
Min
Max
+13.01
(1 V)
1
V
Reference full scale (CAL) 10 cm
-0.97
(0.2 V)
0.2
V
9.7
10.3
-6.99
(0.1 V)
0.1
V
9.7
10.3
-20.97
(20 mV)
20
mV
9.7
10.3
-26.99
(10 mV)
10
mV
9.7
10.3
-40.97
(2 mV)
2
mV
9.7
10.3
-46.99
(1 mV)
1
mV
9.7
10.3
-60.97
(0.2 mV)
0.2
mV
9.7
10.3
b. Adjustments. No adjustments can be made.
16. Frequency Response
a. Performance Check
(1) Position controls as listed in (a) through (c) below:
(a) AMPLITUDE MODE LOG 10 dB/DIV pushbutton pressed.
(b) AMPLITUDE REF LEVEL switch to -30 dB.
(c) INPUT SENSITIVITY SWITCH (white marker) to 0 (zero) dBv.
(2) Adjust calibrator frequency to 10 kHz at +13.01 dBm (1.0 V) output amplitude.
(3) Alternately press and release DISPLAY CLEAR WRITE pushbutton while
adjusting SWEEP MODE MANUAL VERNIER control to center display (a
narrow spike).