TM 11-5840-360-14-1-1
CAUTION
CAUTION
1. WHEN RAISING OR LOWERING
1. USE CARE TO AVOID DAMAGE
THE
PEDESTAL
HOUSING,
EXERCISE CARE TO PREVENT
TO THE ANTENNA ARRAY WHEN
DAMAGE TO THE ROTARY JOINT AS
LIFTING THE PED ESTAL INTO ITS
IT PASSES THROUGH THE FIXED
SERVICE POSITION.
BASE PLATE.
2. WHEN RAISING OR LOWERING
2.
EXERCISE CARE TO AVOID
THE
PEDESTAL,
EXERCISE
DAMAGE TO THE ANTENNA ARRAY
EXTREME
CARE
TO
AVOID
WHEN RAISING OR LOWERING THE
DAMAGING THE ROTARY JOINT AS
PEDESTAL HOUSING .
SEMBLY AS IT PASSES THROUGH
THE FIX ED BASE PLATE.
4. Grasp the handle at the rear of the pedestal and
carefully raise the pedestal housing until it locks into its
Access to the antenna drive motor is obtained
service position.
by removing the domed cover located on the top rear of
the pedestal. Access to the resolver and heading line
5. Loosen the four motor mounting bolts. Using a
switch adjustment arms (and, for V4 systems, the
screw driver, apply pressure to the notches on the motor
synchro adjustment arm) is provided by removing the
mounting plate to loosen the belt.
small cover plate at the front of the pedestal housing.
6. Move the motor mounting plate until the belt
can be slipped off the drive sheave.
5.11.1 Troubleshooting Procedure
7. Remove the screw, washer and lock washer
which hold the anti-rotation plate to its mounting post.
Fault isolation within Antenna Pedestals AB1247
8. Slip the belt off the drive sheave and between
and AB-1247A is facilitated by use of Troubleshooting
the anti-rotation plate and its mounting post; remove the
Chart, Figure 5-5.
Instructions for use of the
belt.
troubleshooting chart are given in paragraph 5.9.1.
9. Slip replacement belt between the anti-rotation
plate and its mounting post; replace and tighten anti-
5.11.2 Removal/Replacement Procedures
rotation plate mounting hardware.
Before initiating any removal or replacement
NOTE:
activity at Antenna Pedestals AB-1247 or AB-1247A,
Do not stretch the replacement drive
insure that all power is removed from the equipment by
belt. If necessary, move the motor
performing the following steps:
mounting plate until the belt slips
over the sheaves easily.
1. Set POWER switch to OFF at (master) Indicator
for associated Receiver Transmitter RT-1240.
10. Slip the replacement belt over the sheaves and
seat it in the outer grooves; move the motor mounting
2. Turn off and tag ship's circuit breakers which
plate to tense the belt, then finger-tighten the four motor
supply power to associated Receiver Transmitter RT-
mounting bolts.
1240.
11. Adjust be It tension per paragraph 5.7.1.3.
3. Set ON/OFF Safety switch at front of pedestal
to OFF.
5.11.2.2 Drive Motor B1. - See Figure 5-4; refer to
assembly drawings in Chapter 6, Section 6.3 as
5.11.2.1 Drive Belt. - See Figure 5-4; refer to assembly
necessary.
drawings in Chapter 6, Section 6.3 as necessary .
1. Insure power is removed from pedestal per
1. Remove power per paragraph 5.11,2.
2. Disconnect the waveguide from the rotary joint.
2. Remove drive belt per paragraph 5.11.2.1.
3. Loosen the twelve captive screws in the bottom
3. Remove the eight screws and washers which
of the pedestal fixed base plate.
secure the motor cover to the top of the pedestal and
remove the cover.
5-26
Previous Page
