TM 5-6350-264-14&P-5
NAVELEX EE 181-AA-OMI-060/E121 SA-1955
T.O. 31S9-2FSS9-1-5
Table 5-1. Troubleshooting Procedures-Continued
Trouble
Probable cause
Corrective action
1. (cont.)
c. Bad tamper alarm switch.
a. Remove cover, and disconnect
wire from TB1-6. Set multimeter
to ohms; and check TB1-5 and
TB1-6. Meter should indicate over
100,000 ohms
b. Depress tamper alarm switch
(TAS) arm. Meter indication
should change to less than 50
ohms
.
c. If these indications are not correct,
replace PC board.
d. To remove the PC board, tag and
disconnect the wires from TB1.
Remove two screws that secure
the bias magnet and two screws
that secure PC board to the hous-
ing. Remove the PC board,
e. To install new PC board, orient the
board so that the terminal strip
is on the side away from the Act-
uating Magnet. Secure the board
to the housing with screws. Put
the bias magnet in place, and
start the screws that secure it;
but leave these screws loose so
the bias magnet can be calibrated.
Connect the wires to TBl.
f. To calibrate the bias magnet, set
the meter to ohms and connect the
leads to TB1-1 and TB1-2. Loosen
the two screws that secure - the
bias magnet to the PC board.
Close the door or window. Slide
the bias magnet back and forth
until the meter indicates less than
50 ohms.
g. Open the door or window 1/2 inch
(1.27 cm). The meter should in-
dicate less than 50 ohms.
5-5
