TB 9-6625-2291-24
10. Attenuation Mode
a. Performance Check
(1) Ensure FC end of optical fiber jumper cable is connected to FOCUS-LWCM
OPTICAL I-O and connect biconic end to lightwave multimeter OPTICAL INPUT port.
(2) Set FOCUS-LWCM output for lightwave multimeter indication of -20.00
0.01 dBm.
(3) Carefully remove optical fiber jumper cable connection from lightwave
multimeter OPTICAL INPUT port and connect to RECEIVE port.
(4) Press ATTENUATION MODE (dB) -40 pushbutton (in).
(5) If TI does not indicate between -20.20 and -19.80, perform b below.
(6) Press ATTENUATION MODE (dB) -20 pushbutton (in).
(7) If TI does not indicate between 00.20 and -00.20, perform b below.
(8) Press ATTENUATION MODE (dB) -25 pushbutton (in).
(9) If TI does not indicate between -05.20 and -04.80, perform b below.
(10) Press ATTENUATION MODE (dB) -30 pushbutton (in).
(11) If TI does not indicate between -10.20 and -09.80, perform b below.
(12) Press ATTENUATION MODE (dB) -35 pushbutton (in).
(13) If TI does not indicate between -15.20 and -14.80, perform b below.
b. Adjustments
(1) Perform a (1) through (4) above.
(2) Adjust A2R48 (fig. 1) for TI indication between -20.01 and -19.99 (R).
NOTE
If out-of-tolerance condition still exists, A2R43 and A2R3 may
need to be readjusted slightly according to paragraph 9 above;
then repeat paragraph 10.
11. Final Procedure
a. Deenergize and disconnect all equipment.
b. Annotate and affix DA label/form in accordance with TB 750-25.
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