cleanliness is imperative. Instead of merely
49. Moistureproofing and Fungiproofing
adding new lubricants at regular intervals, when-
After Repairs
ever practicable clean and lubricate all moving
If the coating of protective varnish is punctured
parts. If it is possible, inspect and clean the
or broken during repair, and if a complete treat-
equipment daily. In any case, inspect the air
ment is not needed to reseal the equipment, apply
filters and similar protective devices every day
a brush coat to the affected part. Be sure the
and clean them whenever necessary. Refer to
break is sealed completely.
TB SIG 75 (Desert Maintenance of Ground Signal
Equipment). Some of the problems encountered
50. Winterization
are the following:
Special precautions are necessary to prevent
a. Lubricants become thin and drain rapidly
poor performance or total operational failure of
from moving metal and fiber parts.
equipment in subzero temperatures. Most signal
b. Foreign matter, such as dirt, dust, and sand,
equipment can be used in winter if difficulties
acts as an abrasive. This causes excessive wear,
common in low temperatures are anticipated and
clogging of air cleaners, and impeding of the flow
precautions are taken to prevent them. For oper-
of air.
ational purposes, place the equipment in heated
rooms whenever possible. Take measures to keep
52. Lubrication
the temperature of the fork oscillator unit above
The effects of extreme cold and heat on materials
+32 F. Refer to TB SIG 66 (Winter Main-
and lubricants are explained in TB SIG 69
tenance of Signal Equipment), and TB SIG 219
(Lubrication of Ground Signal Equipment). Ob-
(Operation of Signal Equipment at Low Temper-
serve all precautions outlined in TB SIG 69 and
atures) for complete information. The following
pay strict attention to all lubrication orders when
problems may be encountered:
operating the equipment under conditions of
a. Steel shrinks and becomes brittle in subzero
extreme cold or heat.
temperatures.
b. Glass is especially susceptible to sudden tem-
perature changes. The difference between a low air
a. When the finish on the transceiver and power
temperature and the warmth of a man's breath
unit chassis or the table has been badly scarred
may be sufficient to shatter a lens.
or damaged, rust and corrosion can be prevented
c. Pure rubber resists cold weather well, but
by touching up bared surfaces. Use No. 00 or
certain types of synthetic rubber are unreliable
No. 000 sandpaper to clean the surface to the bare
and become brittle.
metal until a bright smooth finish is obtained.
d. Canvas freezes and loses its pliability in cold
Caution: Do not use steel wool. Minute
weather.
particles frequently enter the equipment and cause
harmful internal shorting or grounding of circuits.
parts to stick and dry.
b. When a touch-up job is necessary, apply paint
51. Rustproofing
with a small brush. Remove rust from the case
Signal Corps equipment operated in desert
by cleaning corroded metal with solvent (SD).
localities is affected by the extremely high temper-
In severe cases, it may be necessary to use solvent
atures and the amount of dirt, dust, sand, and
(SD) to soften the rust and to use sandpaper to
other foreign matter in the air. Keep such ele-
complete the preparation for painting. Paint used
ments from filtering into lubricated parts. Cover
will be authorized and consistent with existing
the equipment when it is not in use. Thorough
regulations.
Section V. TROUBLESHOOTING AT ORGANIZATIONAL MAINTENANCE LEVEL
54. General
is based on the performance of the equipment and
the use of the senses in determining such troubles
a. The troubleshooting and repairs that can
be performed at the organizational maintenance
as burned-out tubes, cracked insulators, etc.
level (operators and repairmen) are necessarily
limited in scope by the tools, test equipment,
which component is at fault and in localizing the
replaceable parts issued, and by the existing
fault in that component to the defective stage or
tactical situation. Accordingly, troubleshooting
items such as a tube or fuse.
