TM 11-6625-2398-15-3
(1) Connect one multimeter test lead to VIDEO
the multimeter test leads to the first two etched
connector J1 on the front panel. Successively connect
terminals on one side of the board. Move the two
the other test lead to plug P1 contacts listed below.
multimeter test leads successively, by advancing each
Rotate the VIDEO switch to the position corresponding
test lead one terminal at a time, across the board.
to the plug contact below for each test. The meter must
Repeat for the etched terminals on the opposite side of
indicate zero ohms (continuity) for each switch position.
the board. The meter must indicate open circuit for
each test.
Plug P1 contacts
VIDEO switch position
R
RETURN (GND)
(2) Check board continuity by progressively
M
ISLS GATE
connecting one multimeter test lead to the etched
N
CHAL VIDEO
terminals at one end of the board, connect the other test
C
SUM IF VIDEO
lead to the corresponding connector contacts at the
D
DIFF IF VIDEO
opposite end of the board. The meter must read zero
P
MOD PULSE
ohms (continuity) for each etched terminal.
F
RCVR VIDEO
J
CHAL MON DET INCIDENT PWR
(3) Check for short circuits by successively
K
CHAL MON DET REFL PWR
connecting the multimeter test leads to etched terminals
back-to-back on opposite sides of the boards. The
(2) Successively connect the multimeter test leads
meter must indicate open circuit.
to the connectors and plug P1 contacts listed below.
The meter must read zero ohms (continuity) for each
(4) Check continuity to test points on the board by
test.
connecting one multimeter test lead to the first contact
of J45 and the test point (J1 or J2) immediately below.
Connector
Plug P1 contacts
Advance test leads successively across the board to the
GND J8
R
last contact of J45 and the last test point (J43 or J44).
RT FAULT J2
G
Repeat for the opposite side of the board. The meter
LVPS MON J3
E
must indicate zero ohms (continuity) for each test point.
CHAL MON ENABLE J4
H
SUM XTAL CUR J5
B
h. Extender Board A5. (fig. 6-22)
ISLS INHIBIT J6
L
DIFF XTAL CUR J7
A
(1) Check for short circuits by connecting the
multimeter test leads to the first two adjacent pins on
(3)Connect the multimeter test leads to VIDEO J1
one end of the board. Move the two multimeter test
and GND J8 front panel connectors. Rotate the VIDEO
leads successively, by advancing each test lead one pin
switch successively to the positions listed below. The
at a time, across the board. The meter must indicate
meter must indicate open circuit for each test position.
open circuit for each test.
ISLS GATE
MOD PULSE
(2) Check board continuity by progressively
CHAL VIDEO
RCVR VIDEO
connecting the multimeter test leads to the
SUM IF VIDEO
CHAL MON DET INCI-
corresponding pins at each end of the board. The meter
DENT PWR
must read zero ohms (continuity) for each set of pins.
DIFF IF VIDEO
CHAL MON DET
REFL PWR
i. Front Panel Test Adapter. (fig. 6-20)
NOTE
The meter will read zero ohms (continuity)
with VIDEO switch in RETURN (GND) position.
4-5
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