TM 9-4935-294-15/2
(3) Free connector bracket assembly (3, fig. 4-28)
(6) Place waveguide assembly (11, fig. 4-28) on
by removing attaching screws (4).
the tube output connector. Attach with four screws (9)
(4) Place connector bracket assembly (3) on the
inserted through the waveguide flange and output
adjacent work surface so that back of connector and
connector engagement. Secure with four washers (7)
back of dispersion PC board assembly (refer to 1, fig.
and four nuts (6).
(7) Place assembled tube and waveguide
further disassembly.
assembly in proper position within rf head chassis (42)
(5) Unsolder and remove red harness lead from
and aline tube brackets with mounting holes. Insert
terminal 2 on the dispersion PC board assembly (refer to
screws through rf head chassis (42) into the mounting
1, fig. 4-12).
brackets. Do not tighten at this time as tube must be
(6) Remove male connector contacts 7, 16, and
free to move.
Note. Tube harness is routed between the bottom of
19 (refer to 13, fig. 4-12) from connector (10, fig. 4-
12). Follow applicable procedures outlined in paragraph
the chassis and the tube.
4-17 e (1).
(8) Carefully aline flange of waveguide assembly
(7) Remove the following attaching hardware from
(11) with flange of directional coupler (18) and
waveguide support (39, fig. 4-28) and directional
waveguide support (39). Insert two screws (8) through
coupler (18) flange engagement in indicated order:
this engagement and secure on the coupler side with two
(a) Four hex nuts (6).
washers (7) and nuts (6). Insert two screws (9) through
(b) Four washers (7).
the other side of the waveguide and directional coupler
flanges and secure with two washers (7) and two nuts
(c) Two screws (8) from waveguide support
(6).
side.
(d) Two screws (9) from flange engagement.
(9) Apply sealing compound A10528558 to BWO
tube bracket mounting screws (4), then tighten. Check
(8) Remove four screws (4) from the tube support
position, routing and condition of harness.
brackets.
(10) Connect and solder the red harness lead to
(9) Slide BWO tube (5) and waveguide assembly
terminal 2 on dispersion PC board assembly (refer to 1,
(11) from rf head chassis (42).
(10) Disassemble waveguide assembly
(11) Install connector bracket assembly (3, fig. 4-
(11) and BWO tube by removing four hex nuts (6),
28) on rf head chassis (42). Attach with two screws (4),
four washers (7), and screws (9).
and secure.
b. Replacement of BWO Tube 7923112.
(12) Connect and solder the green, orange, and
(1) Obtain a replacement BWO tube; unpack and
blue harness leads to connector bracket assembly (3)
inspect for possible shipping and/or handling damage. If
solder lug (refer to 17, fig. 4-12).
BWO tube is in satisfactory condition, proceed with the
(13) Install side cover (1, fig. 4-28) with 10 screws
installation. Perform installation procedures in a location
(2).
free from possible magnetic fields. Use a work surface
c. Disassembly of K-Band Rf Head. To disassemble
that is non-magnetic.
the K-band rf head completely, follow order of removal
(2) Remove protective cover from the output
shown in exploded view, figure 4-28, and refer to wiring
connector.
diagram, figure
(3) Obtain three replacement male connector
4-29. Remove and replace mixer diode as follows:
contacts 7923076. Obtain installation and crimping
(1) Unscrew knurled nut of mixer (17, fig. 4-28).
tool 7919871.
(2) Remove diode, and replace, if required.
Note. To install the male connector contacts, follow
Note. For disassembly and assembly of the connector
the applicable procedures outlined in paragraph 4-17
bracket assembly and counter assembly, refer to e and
e(2) (a).
f, respectively, below.
(4) Install male connector contact 19 (refer to 13,
(5) Install male connector contacts 7 and 16 on
yellow
harness
(heater)
leads.
Change 1 4-46
