VTM-91-772/C
-8-
b. Before assembling the two sections together, the sleeve at top of the bottom section must be
coated with a thin layer of electrically conducting nickel-based anti-seize compound MIL-A-
907E (supplied). A small dab of anti-seize in each of the eight threaded holes will assist
with installing the screws later.
c. Place the bottom section of the antenna on two saw horses. After applying the anti-seize
compound to the mating sleeve, carefully slide the antenna top section over the sleeve
making sure the arrows on each section are aligned.
d. Ensure the eight holes are in line between the two sections. Install the eight countersink flat
head screws to the two sections. It is recommended to install all eight screws 3 or 4 turns
before tightening any of them.
e. Begin tightening the screws one by one. A minimum torque of 10-20 in-lbs is required to
install the screws. If less than this torque is used, the thread-locking inserts may be damaged
and need to be replaced. Contact the factory for assistance. A final torque between 55-75
in-lbs is acceptable for the screws, providing the screw head sits flush or slightly below the
antenna surface. After installation, seal the screw heads using the RTV sealant.
f.
Carefully lift the antenna to its mounting platform. Align the mounting holes of the base
flange with the mounting holes in the platform.
g. Secure the antenna to its mounting plate with using eight 5/8-11 hex head cap screws (not
provided), along with two flat-washers, a split-lock-washer and a nut. Bolt length will need
to be determined by the installing activity. A final torque between 90-100 ft-lbs is
acceptable for the bolts.
h. Connect the system feedline to the antenna at any one or all of the three feedpoints as
required.
4-7. INSTALLATION CHECKOUT
Checkout of the antenna after installation can only be accomplished by operating the receiving and
transmitting equipment that is used with the antenna.
Note: If replacing an existing antenna with a new antenna, it is recommended that new
mounting hardware be used.
