TM 9-4935-294-15/2
Section IV. DISASSEMBLY AND ASSEMBLY OF RF PLUG--IN HEADS
Caution. The soldering iron used should be pencil
4-16. General
a. This section contains instructions and information
type, 15 watts or less, connected through a
necessary for the disassembly and assembly of
thermostatically controlled stand. Apply soldering
the following rf heads:
iron so it touches solder point only.
P--band (0.5--1 GHz)----7923020
L--band (1--2 GHz)--7923021
(2) Unsolder and remove the yellow and green
S--band (2--4 GHz)--7928022
harness leads from connector bracket assembly (8)
C--band (4--8 GHz) and X--band (8--12.4 GH--7923023
U--band (12.4--18 GHz)--7923024
(3) Remove clamp (3, fig. 4) by removing hex nut
K--band (18--26.5 GHz)--7923025
(4), lockwasher (5), flat washer (6) and screw (7).
A--band (26.5--40 GHz)--7923026
(4) Free connector bracket assembly (8) by
b.
Each procedure includes instructions for the
removing attaching screws (9).
(5) Place connector bracket assembly (8) on the
tube, which is accomplished with minimum disassembly
adjacent work surface so that back of connector and
of the rf head. In addition, instructions and information
back of dispersion PC board assembly (refer to 1, fig. 4-
are given for the disassembly and assembly of the
12) are accessible and in a convenient position for
connector bracket assembly and counter assembly in the
further disassembly.
rf head.
(6) Unsolder and remove the blue harness lead
from terminal 2 on dispersion PC board assembly (refer
4-17. Disassembly and Assembly of P-band
Rf Head
To disassemble the P--band rf head, refer to exploded
disconnect adapter directional coupler (22).
view, figure 4--10, and wiring diagram, figure 4--11, and
(8) Remove four nuts (15), four washers (5), and
follow procedures a through d below.
four screws (16) from tube brackets (17).
Note. Systems with serial nos. 127 and up use PC
(9) Slide BWO tube (14) from rf head chassis (41).
board assembly 7923063--2 for item 27 and systems
(10) Remove male connector contacts 7, 16, 19 and
with serial nos. 101--126 use 7923067--1.
23 (refer to 13, fig: 4-12) from connector (10, fig. 4-12).
Follow applicable procedures outlined in e (1) below.
a. Removal of BWO Tube 7923106. Before removing
(11) Remove two tube brackets (17, fig. 4-10) from
BWO tube, read and observe all instructions appearing
BWO tube (14) by removing four screws (18) and four
on the tube and rf head case. Since BWO tube
washers (5).
emanates strong magnetic fields, all work must be
b. Replacement of BWO Tube 7923106.
performed in a location free from possible magnetic
(1) Obtain a replacement BWO tube; unpack and
fields.
Work surfaces and tools must be non
inspect for possible shipping and/or handling damage. If
BWO tube is in satisfactory condition, proceed with the
installation. Perform installation procedures in a location
follows:
free from possible magnetic fields. Use a work surface
that is nonmagnetic.
Caution. Exercise extreme care when removing
Caution. The balun and N connector are in-
BWO tube to avoid damage to adjacent and related
tegral parts of BWO tube and should not be
electronic, electrical and mechanical components
disassembled.
and assemblies.
(2) Remove protective cover from the output
connector.
removing 10 screws (2) attaching it to rf head chassis
(41).
Change 1 4-13