TB 9-6625-2235-24
Figure 14. A14 log amplifier - adjustment locations (SN prefix 2142A and below).
Table 11. Linear Gain
Variable
Test instrument
REFERENCE LEVEL
attenuator
Deviation from
dBm
crt
10 dB step
reference1
switch settings
control setting
(dBm)
(dB)
2 div
-50
0
2 div
-60
10
2 div
-70
20
2 div
-80
30
2 div
-90
40
(41) Set signal generator RF output to STBY position. Record multimeter indication
as offset value.
(42) Set signal generator RF output to on and press TI 10 dB/DIV pushbutton in.
(43) Set variable attenuator 10 dB step control to 40 dB and adjust signal generator
RF output controls for a multimeter indication of 400 mV plus offset value recorded in (41)
above. (Refer to (8) above for examples on adding offset value to multimeter indication).
(44) Set variable attenuator 10 dB step control to 0 dB. Multimeter will indicate
800 mV, 1 mV (plus offset value recorded in (41) above). If not, adjust A14R2 (fig. 14) for a
multimeter indication of 800 mV plus offset value recorded in (41) above (R).
(45) Set variable attenuator 10 dB step control to values as listed in table 12. Record
multimeter indication for each variable attenuator 10 dB step control setting. Correct
multimeter indications by algebraically adding offset value recorded in (41) above and
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