TM 9-6115-669-13&P
POTENTIOMETER
a.
Record labeling and position of cables, and unsolder cables from terminals of potentiometer R1
(15).
b.
Remove cover cap (10) from knob (11).
c.
Using fork-head screwdriver, remove slotted nut in knob (11).
d.
Remove nut (12), and graduated dial (13).
e.
Pull potentiometer R1 (15), and serrated lock washer (14), from the back of the front panel.
NOTE
For this test potentiometer R1 (15) must be connected to control
board (5) complete with heat sink (7) power transistor.
Use DC power supply to check brightness control:
a.
Connect 24 VDC to terminal 2 (+) and terminal 1(-).
b.
Set multimeter for DC voltage and connect between terminal 4 and terminal 1.
c.
Turn potentiometer from full left to full right position. Multimeter must display 0 - 24 VDC.
BRIGHTNESS CONTROL
a.
Place control board (5) on heat sink (7).
b.
Install two nuts (6) on heat sink (7).
c.
Solder to pins (9) of power transistor on control board (5).
d.
Place heat sink (7) on mounting bar.
POTENTIOMETER
a.
b.
C.
d.
e.
f.
g.
h.
Install potentiometer R1 (15) and serrated lock washer (14) into panel from behind.
Install graduated dial (13) onto shaft and secure potentiometer with nut (12).
NOTE
Turn potentiometer shaft all the way counterclockwise, and set knob
pointer to zero on graduated dial (OFF position).
Install knob (11) onto shaft, position and secure with internal slotted nut using fork-head
screwdriver.
Place cover cap (10) on knob (11).
Solder cables on potentiometer R1 (15).
Remove stanchion.
Stow prop (3), close access door (2) and indicator panel cover (4) and secure.
Install stanchion by PDU (1).
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