TB 9-6625-862-24
13. Input Attenuation
a. Performance Check
(1) Set OUTPUT ATTENUATOR (DB) (OUTPUT DB) 0 to 10 switch to 0.
(2) Adjust AMPLITUDE (OUTPUT) control for a 0.775 V ac indication on
multimeter. Record INPUT LEVEL meter indications.
(3) Set INPUT ATTENUATOR (DB) (INPUT DB) switch to settings listed in
table 9, while adjusting AMPLITUDE control setting OUTPUT ATTENUATOR (DB)
(OUTPUT DB) switches as required for INPUT LEVEL meter indication recorded in (2)
above. Multimeter indications will be within limits specified.
b. Adjustments. No adjustments can be made.
Table 9. Input Attenuator Check
Test instrument INPUT
Multimeter indications (V or (DB))
ATTENUATOR (DB) switch
Min
Max
settings
5
1.362
(4.9)
1.394
(5.1)
10
2.422
(9.9)
2.479
(10.1)
15
4.308
(14.9)
4.408
(15.1)
20
7.661
(19.9)
7.839
(20.1)
25
13.623
(24.1)
13.941
(25.1)
30
24.227
(29.9)
24.791
(30.1)
35
43.082
(34.9)
44.086
(35.1)
40
76.612
(39.9)
78.397
(40.1)
14. Final Procedure
a. Deenergize and disconnect all equipment.
b. Annotate and affix DA label/form in accordance with TB 750-25.
