c. Disassembly of L-Band Rf Head. To disassemble
the L-band rf head completely, follow the order of
419. Disassembly and Assembly of S-Band Rf Head
To disassemble the S-band rf head, refer to exploded
connector bracket assembly and counter assembly, refer
to e and f, respectively, below.
follow procedures a through d below.
d. Assembly of L-Band Rf Head. To assemble the L-
a.
Removal of BWO Tube 7923108.
Before
removing BWO tube, read and observe all instructions
appearing on the tube and rf head case. Since BWO
disassembly.
tube emanates strong magnetic fields, all work must be
Note.
Apply sealing compound 10528558
or
performed in a location free from possible magnetic
10528557, as applicable and required, to all screws not
fields. Work surfaces and tools must be non-magnetic.
e. Disassembly and Assembly of Connector Bracket
Assembly. To disassemble and assemble the connector
Caution. Exercise extreme care when removing
BWO tube to avoid damage to adjacent and related
electronic, electrical and mechanical components
f.
Disassembly and Assembly of the Counter
and assemblies.
Assembly.
(1) Disassembly. To disassemble the counter
removing 10 screws (2) attaching it to rf head chassis
assembly, follow the order of removal shown in exploded
(41).
15.
(2) Assembly.
To assemble the counter
pencil type, 15 watts or less, connected through a
thermostatically controlled stand. Apply soldering
iron so it touches solder point only.
disassembly. Observe the following procedures:
(2) Unsolder and remove the yellow and green
harness leads from connector bracket assembly (8)
counter assembly (19) with type III, MIL-E-5092A
adhesive.
(b) Obtain gears (16) and (17). If they are
nut (4), lockwasher (5), flat washer (6) and screw (7).
replacements, ascertain that they are the proper parts
(4) Free connector bracket assembly (8) by
and have been inspected.
removing attaching screws (9).
(c) Turn variable resistor R1502 (18) fully
(5) Place connector bracket assembly (8) on the
ccw.
adjacent work surface so that back of connector and
(d) Set dials of counter assembly (19) to low
back of dispersion PC board assembly (refer to 1, fig. 4-
12) are accessible and in a convenient position for
(e) Install gear (17) on counter assembly (19)
further disassembly.
shaft and engage with gear (16). Do not tighten
(6) Unsolder and remove the blue harness lead
setscrew.
from terminal 2 on the dispersion PC board assembly
(f) Install gear (16) on the shaft of variable
resistor (18). Do not tighten setscrew.
(g) Check counter setting and position of
disconnect adapter (20).
variable resistor (18). Both settings must be as specified
(8) Remove four nuts (15), four washers (5) and
in (c) and (d) above.
four screws (16) from tube brackets (17).
(h) Secure gears to respective shafts with
setscrews.
Change 1 4-25