(20) On the blower mounting bracket (through
necessary, disengage and lock the latches to accomplish
the top opening) loosen the two captive screws down in
(12) Extend the PA from the rack.
(21) Remove the two flathead screws securing
(13) On the rear of the PA, connect the ground
wire to terminal E4. Connect the two cable plugs to
(22) At the left and right ends of the bracket
connectors J3 and J4.
remove the screws securing the bracket to the chassis.
(14) Close the PA drawer and tighten the eight
(23) Note the orientation of the bracket and
captive screws on the front panel.
then remove it.
(15) Connect the front panel cables to the SHF
(24) On the rear panel of the PA remove the
IN and SHF TEST OUT connectors.
four screws that secure the blower to the chassis.
(25) Check that the blower power wires are
Handle the waveguides with care. If
free of any obstructions. Remove the blower through the
damaged they may cause equipment
top of the PA.
d. Replacement of Power Amplifier Blower B1.
(16) On the front panel, mate the SHF OUT
waveguide flange with the shelter waveguide flange and
Remove your watch to prevent it from
lock the quick disconnect clamp.
e. Removal of Klystron V1.
(1) Insert the blower through the top of the
PA. Dress the blower power wires to the right side and
Use the nonmagnetic tools provided
towards terminal board TB1.
with the shelter tool kit to remove the
(2) Insert the four screws through the rear
panel into the blower but do not tighten.
(3) Place the blower mounting bracket, in the
Do not allow magnetic tools,
proper orientation, on the chassis mounting.
hardware, etc., to be pulled into the
(4) At the ends of the bracket, insert and
tighten the screws to secure the bracket to the chassis.
rapping the magnet can alter its beam
(5) Insert two flathead screws through the
focusing properties and damage the
bracket into the blower output flange; do not tighten.
tube. Also remove your wristwatch to
(6) In the bracket well engage two captive
screws with the blower housing. Tighten these screws
and those in steps (2) and (5) above.
(1) Observe the warning note under
(7) Through the right side access opening,
dress the three blower power wires above terminal board
Handle the waveguides below with
(8) Connect the three wires to terminals TB1-
care. If damaged, they may cause
1, 2, and 3; tighten the screws. Remove the tags and
refasten the cable clamp.
(2) On the power amplifier (PA), unlock the
(9) Through the top opening, replace the
quick disconnect clamp securing the PA SHF OUT
flexible plenum on the blower and klystron mounting
waveguide flange to the shelter waveguide flange and
flanges. Tighten the screw on each hose clamp to
free the mated flanges.
secure the flexible plenum.
(3) Remove front panel cables from the SHF
(10) Replace the right side access cover, the
IN and SHF TEST OUT connectors.
front access cover, and the top cover on the PA. Tighten
(4) Loosen the eight captive screws on the
all 1/4-turn fasteners.
front panel of the PA.
(5) Pull on the two handles to extend the PA
Because of the bulk and weight of the
from the rack.
PA, use two persons to replace it.
(6) Loosen the twelve 1/4-turn fasteners
Handle the PA with care; otherwise,
which secure the top cover.
damage to the PA or injury to
(7) Remove the top cover.
personnel may result.
(8) Loosen the twelve 1/4-turn fasteners
(11) Engage the unit slide rails with the rack
which secure the bottom cover.
chassis slide rails and push the PA into the rack. As
(9) Remove the bottom cover.