Operating instructions

i,earing
surfaces
of srvitch detents,
band-su'itch
nrechanisms. ancl fasteners, and sparingly apply
oil, lubricating,
preservative,
special
(PL-Spe-
cial). Remove excess oil to
prevent possible
mal-
functioning of other
parts,
especially srvitch
contacts.
b. Approximately once every 6 months, lu-
bricate the tuning drive
gears.
Expose
the
gears
by removing the
receiver from
the
cabinet
and the top cover
from
the receiver, and
r,vhere
possible,
wipe the
gears
clean r,vith a lint-free
cloth moistened u'ith solvent
(SD)
;
then
u'ipe
u'ith
a
dry
cloth.
Lubricate
by appli'ing Grease
MIL-G-3278
to the
gear
teeth,
and turn the
gear
assembly to spread a
light
coating
of
grease
evenly on all
gear
teeth.
lVipe
au'a-v
excess
grease
from face of
gears.
Nole. If
grease
is removed from
the
tt'o setsclervs
located on the dial-gear hub of tl-re
geal
assembly,
it
shor-rld be
replaced.
ú.
Grease
MIL-G-3278 contains a rust and
corrosion
inhibitor. It may
be
used in regious
u-hich huve tempet'atllt'es ranging from
-70u
tr to
-160
F.
37.
Lubricotion
Under
Unusuol
Conditions
u. Arctic flr
qi,,,,s.
I-ul.rlicants rvhich
are
satisfactory
at
morlelate tenrpei'atures stiffen
and solidify
at
subzerr) tenllrelirttìi'es;as a re-
sult, moving
palts
bincl
ol become inoperative.
When
preparing
the ecluipnrent
î,,r krrv-tem-
perature
operation,
see
that lulrlicant-s used
for
moderate
temperatures
are tholoughll' re-
moved. Even
small amoLrnts of
such lribi'ictrnts,
if allorved to remain, maf impair the opelation
of moving
parts.
Be sure
to use Grease
IIIL-
G-3278 as specified.
b. Tt'opical
or Desert
Reyytons.
High
tem-
peratnres
and
moisture caused
by
rain, conclen-
sation,
etc., may cause
lllbricants lvhich
are
normally
satisfactory bo florv from moving
parts
ancl other surfaces. Inspect the equipment cìaily
ancl
lubricate it
as
reouired
: use Grease
I'IIL-
(]-3278.
Section
lV.
WEATHERPROOFING
38. Weqtherproofing
a. Gettersl. Signal Corps eqlripment,
$'herÌ
operated
Lrnder severe climatic
conditions such
as
prevail
in tropical, ai:ctic,
and clesert regions,
requires special treatment
ancl
maintenance.
Fungus
grou'th,
insects, dttst, corrosion,
salt
spray,
excessive
moisture,
and
extreme tem-
peratnres
are
harmful to most materials.
b. Tropicctl
X'Iaintenance. A special
mois-
tureproofing ancl
fungiproofing
treatment
has
been
clevised
u'hich,
if
properll'
appliecl,
pro-
vides
a reasonable
tlegree of
protection.
This
treatment
is explained
in
TB
SIG
13
and
TB
SIG
72.
The equipment
is
given
the
moisture-
proofing
and fungiproofing
treatment
at the
factory and
it
is
only
necessary to use this
treatment
rvhen
parts
are
replaced or
repaired.
c. Deset't
X[aintenunce. Special
precautions
necessary to
prevent
equipment
failure
in
areas
.ubject
to
extremely
higih temperatures,
low
:rLrmiclity,
and
excessive
sand and
clust are ex-
,l:rinecl
in TB SIG
75.
rI
. \f/inter
Maintenattce.
Special
precautions
24
necessary
to
prevent poor performance
or total
operational failure
of equipment
in
extremely
lou'
temperatures are explained
in TB
SIG
66
:rnd
TB
SIG
219.
39.
Rurstproofing
ond
Poinfing
a.
When the
finish on the case has been
badly
scarred
or damaged, rlìst and corrosion can be
prevented
by touching up bared
surfaces.
Use
No. 00 or No. 000
sanclpaper to clean the snrface
clorvn
to the
bare metal; obtain a bright smooth
finish.
Cuutíon: Do
not
use
steel
u,ool.
Minute
par-
ticles
frequentl;r enter the case and cause harm-
ful internal shorting or
grounding
of circuits.
b.
When
a touch-up
job
is
necessarl',
apply
paint
ivith
a
small brush. Remove rnst from
the case by cleaning corrocled
metal u'ith
solvent
(SD).
In severe cases
it mav be necessary
to
nse
solvent
(SD)
to soften
the rust
and to use
sandpaper
to
complete the
preparation
for
painting.
Paint used
u'ill be
anthorized
and con-
sistent with
existing
regnlations.
AGO 3134