assembly. The control panel assembly is now free to be
4-9. Removal and Replacement of ATU Control
b. Replacement Proceed as follows.
(1) Refer to figure 4-2. Reconnect all tagged
a. Removal Proceed as follows.
wires to the control panel assembly (7).
(1) Refer to figure 4-2.
Using a slot
(2) Reconnect wire removed and tagged in 4-
screwdriver, unlock the ATU front cover (1).
9a(6), above, to terminal 5 of TB1 (4).
(2) Raise the ATU front cover (1) and insert
(3) Secure cable clamp along with cableform
the door support rod (10) into the doorstop bracket (9)
to the control panel assembly (7), using one nut and one
Insert the hitch pin clip through the hole at the end of the
flat washer .
door support rod.
4) Swing the control panel assembly (7) up
(3) Remove two screws (5) and flat washers
onto the two large standoffs and aline the two mounting
(6) securing the control panel assembly (7) to the two
large standoffs Retain the attaching hardware for
(4) Allow control panel assembly (7) to swing
down, so as to expose the connections at the rear of the
Before securing control panel assembly,
ensure that there are not wires which
(5) Remove one nut and flat washer securing
could possibly be pinched between the
the cable clamp to the control panel assembly (7).
standoff and the control panel assembly.
Retain cable clamp and attaching hardware for
(5) Install two screws (5) and flat washer (6)
(6) On the electronic assembly (8), tag and
to secure the control panel assembly (7) to the two
remove one wire from the control panel assembly (7) at
terminal 5 of TB1 (4).
(6) Remove the hitch pin clip from the door
support rod (10) and disengage the door support rod
from the doorstop bracket (9). Insert the door support
rod in the retainer and lower the ATU front cover (1).
There are two wires connected to
(7) Using a slot screwdriver, lock the ATU
terminal 5 of TB 1 Remove only the wire
front cover (1).
which connects to the control panel
(7) Tag and disconnect all wires connected to
the control panel assembly (7) from sources outside the
Section IV. GENERAL SUPPORT TESTING PROCEDURES
There are no special general support testing procedures
repair, general support maintenance personnel must test
for the NDB transmitter, ATU or the change over unit.
the entire unit in accordance with the testing procedures
in TM 11-5825-271-12.