Technical information

O
RADIO
RETAITING'S
".
eZdre
FAIRBANKS
MORSE
FAIRBANKS
MORSE
42
Motorboats
when
volume
is
ad-
vanced
on
strong
stations
sus-
pect
8
nrfd
condenser
or
resistor
con-
nected
to volume
control.
FAIRBANKS
MORSE
.I.I
Loud howl
that disappears
whcn
tone control
is
set to bass
Re-
place
bias
cell in
grid
circuit
of out-
put
tube. Before
replacing,
clean
all
contacts
thoroughly.
FAIRBANKS.MORSE
238T32.
Noisy reception
Due
to vibrator
unit
being tightly
mounted
to the
chas-
sis. The factory
uses
only one
screw in
mounting
this unit
although
it is drilled
and
tapped
for
two.
Insert
I
inch
of
sponge rubber washer
between
the metal
washer
under screw head
and bottom of
chassis. The
marked
improvement is
u'ell
worth the
trouble.
FAIRBANKS
MORSE
CONSOLE
MODELS
Acoustic
feedback
insert
I
in.
rubber
grommets
on screws
betrveen
tone
projector
and soeaker.
FARNSWORTH
FARNSWORTH AT5O
Weak
on short u'aves realign
at l5
nrc.
although iactoly rcconr-
mends
18
nrc.
FARNSWORTH
AKL59
Shock
rvhen
phono pickup
alnr is
touched
break
sl-rield
on wire
connecting
set
chassis ;rnd
phono
arnr
and insert
.1 nrfd conderlser.
FIRESTONE
FIRESTONE
1322.
Speaker rattle
. . . Look for
loose
solder in
speaker.
Microphor:ics
Loosen
condenser
rubber
washers
and
tighten all
nuts
and
screws.
Case
buzz
and rattle
Loosen
Parker-Kalon
screws,
take
cd,ver
off,
bend, replace.
FIRESTONE
R I43I
Dead
in
upriglrt
positiorr,
satisfac-
tory
operation
when
up-sicle-dorvrr.
. Look
for
burned
blaicled lead in
vibrator
can.
FTRESTONE
57425-3
Interrnittent one
oi the i.f.
ternrinal
lugs interrrrittcntll-
shorting
to back
o[
speaker.
FORD
III.
FORD
Lack of
f933
FORD.
To
get
suppression
at
coil remove
the
three scr€ws and
ter-
minal
nut and take
the coil
ofr. Pull
out
the carbon
brush and spring,
saving
the
spring
and discarding
the brush.
Make
a
suppressor from
a
40,000
ohm
one watt carbon
resistor
of
good quality
by cutting it
to the
same tength as
the
old brush.
Clean off
paint
and
file
recess
in one
end
to accommodate the
spring
and
re-assemble
the
coil,
using
the
suppressor
as
a brush. 40,000
ohms
is
recommended
as the
resistance
is re-
duced
by cutting and filing.
FORD 35.
Low
volutue, sensitivity
ok,
cuts on and
off .
Header sPeaker
cone
leads often short
to
steel
spring
used as
their support.
Retnove
leads
from
support to remedy.
1935
FORD. Inability
to
quiet
ig-
.nition
noise, despitc
standard suppres-
sion . A I mike condenser from
the
hot storage battery
connection on the
gasoline
gauge
to
ground
is
essential.
Other
filtering
tricks suggested are:
Complete shielding of hot A lead from
battery to set and shielded wire
from
resistor conncction on
instrument
panel
to
distributor,
removing
old wire.
Ground shield to cowl, engine and
body.
1935 FORD.
Noise
f rom ignition
after
all usual
methods of clearing
it
up
in these
cars
fail.
. . .
Scrape
paint
off
under
side
of hood where
it fits
on the
cloth head of the body. Wrap bare cop-
per
wire around
head and
ground
it
at
each
speed screw
fastening the
head
in
place.
The hood
will then
make
good
electrical
contact with the body and fre-
quently
clears up radiation
of the
racket
to the antenna.
FORD-MAJESTIC.
In types
using
separatof
vibrator,
blown
fuse or
heavy
"A"
drain .
. .
Probably
due to blown
.01,
1000 volt
condenser
located across
power
transformer
secondary.
Replace
with .01,
1200 volt
unit
made up
of two
.02, 600
volt tubulars
if
single
unit
is
not on
hand. Can
containing
trans-
former,
rectifier tube
and vibrator
unit
easily
temoved
by uscrewing
nut and
lock washer
holding
down
unit and
lift-
ing out.
Before
replacing check
contacts
for burned
wires.
Excessive
current
sometimes
melts solder
and
burns two
vibrator
wires.
File
points,
resolder
and
remount.
Failure of 6Y5
in models
using this
type
. . Replace with
84,
changing
socket
to 5
pin
typc
and dis-
carding
wire originally
connccted
to
spray shield.
If excessive
noise
is
heard connect
.25 or .5
mike low voitage
paper
capacitor directly
across
filament
of rectifier.
If filter blows .
replace
with dual
4,
4-6 or
4-8
dual
as value is
not critical.
FORD-UAJESTIC. Repeatedbreak-
ing or fraying of cable
where set is
mounted
in
.floor
.
Use
number l0
spring-steel
piano
wire,
fishing
this
through
from
control
head
end of sleeve'
to
replace
old stranded cable.
With
this
new wire
slack,
a troublesome feature
o(
thc
stranded stuft, disappears.
F
O
R D-MAJESTIC. Persistent
motor
noise when antenna is
off
. . . Due
to leakage
through
ventilating louvres
in back
of case. Cut
piece
of copper
screen
same size as back of chassis and
fasten
to case over touvres
with
self-
threading screws holding
the case to-
gether.
FORD-MAJESTIC. Set conrpletely
dead Plug in and note anrmeter
drain.
I f
abnormally
high
remove
transformer
pack
and replace snrall vi-
brator condenser at side of transformer.
If
screen
voltage is absent
removc
speaker and
plate
cover to
right of
speaker and
then
replace
the brown
re-
si stor.
FORD-MAJESTIC. Set
performs
ok
on
bench,
but when
lid is
pressed
down,
in car, cuts
in and out while
riding . . . .
Put
paper
discs
in top of tube
caps so
that these cannot short
to shietds.
FORD PHILCO
FT6
Intermittent
lorv
volunre re-
place
buffer
conclenser
across rectifier
plates,
(Resistor
in series with
this
condenser).
FORD
PHILCO
FT6
Insensitive
check
a.v.c. actiou.
Connect
a
I
or
2 meg resistor
in place
of the
190,000
ohm resistor
connected
between second
detector cathode
and
25,000 ohm
resistor
in
grid
return of
second i.f. transformer.
Also,
rernove
the
25,000
ohm
bleeder
located belorv
tuning
condenser under
chassis.
FORD-PHILCO
1934. Periodic-drop
in
volume accompanied
by sharp click
Look for
wires to terminals on in-
of
i.f.
coils touching trimmer rivets
changing
condenser capacities.
260
kc.)
FORD.PHILCO I934
Distinct
vibrator
buzz
that
is
hard
to
correct
.
.
.
Take out
75 second
detec-
tor-a.v.c. tube.
If noise
stops
suspect
shaft
collar
holding volume
control to
case.
Another check for this
trouble
is
to
find
low settings of
volume control
more noisy
than higher
settings. Give
collar another
hard turn with
a wrench
to dig through
paint
and slight
cor-
rosion and also run
a
heavy, short
piece
of
braid from
low
point
of
volume
con-
trol to case and solder
well.
This
will
eliminate
all buzz
from this
source.
FORD PHTLCO
ll916l
Volume
decrease wheri control turned
cn full,
distortion
,
open secondary
on second
i.f.; replace.
FORD
-
PHILCO N. No signat,
voltages
and tubes ok . . . See if
padding
condenser soldering lugs mounted on
tuning condenser frame
have
punctured
through insulating
paper glued
to fixed
condenser
can beneath,
grounding
out i.f.
Slip
new
piece
of heavy insulating 6bre
under the lugs,
if this is the trouble,
and
bend
the
tuss
up.
side
and
(
r.f.
high-frequency
er-rd
ohm
cathode
resistor
in
cuit with 6,000
ohms.
FORD 35. Dial
jumps
calibration
.
Remove cog-wheels
from
dial as-
sembly. Lightly beat out cog-wheel
{vhich holds
pointer
with hammer
until
it thoroughly
meshes
with intermediate
drivins
gear.
22
sensitivity
at
Replace 8,000
autodyne
cir-
ie