Philco 800 Service Manual

PHILCO
TRANSITONE
SERVICE BROADCAST
FEBRUARY,
1934
MODEL
8OO RECEIYER
HE MoDEL 800 represents
the latest
developments
in
single-unit automobile
radio.
Compact and easy
to
install,
its performance is
amazing.
A
superheterodyne,
using
seven
of
the latest tubes
de,;igned
for
automobile radio,
it
has Class
B
amplification
lvith tremendous power output and is
equipped
with a
full-size
electro dynamic speaker,
the
same
type
as used
in
high-
priced home
radio
Receivers.
Four-point tone control
is provided to satisfy the individual preference.
Greater sensitivity, a three-section tun-
ing
condenser
givins improved selectivity and fidelity, inherently quiet circuits and
all
the other improvements,
mal<e
this model the outstanding automobile radio.
Added
to this,
the
ease
of
installation characteristic of this model (only
one
unit to install,
one
lead
to
the
antenna
and
one lead
to the ammeter)
makes
it
the most
desirable one
to
sell,
install or
own.
I.
F.
TRANSFORMER
AND
PADDERS
The new style
L
F. transformer complete
with
padders
is
used
in
the
Model
800.
The
padders are placed
in
the top of the
shield
can
one above
the
other.
The
primary
padder is adjusted
by
means
of
the
screw
slot,
accessible
through
the hole
in the top of the
shield
can.
The secondary
padder is adjusted by
means
of
the
small hex
nut,
also
accessible
through the
hole
in
the top
of the
shield.
(See
Figs.
1
and
2.)
The coil
windings
terminate''in leads instead
of
ter-
minals
or
lugs.
The color
scheme
of
the leads
is given in
Fig.
l.
If
replacements
are ever necessary, replace
the
entire
coil
assembly 32-1235
for
the
first
I.
F.
stage and 32-1237
for
the
second
I.
F. stage. Neither
the
coil nor the padders
will
be fur-
nished
separately.
Order
only
by
Frc.
I
the above numbers.
MODEL
BOO ADJUSTMENTS
All
adjustments
have been carefully
checked
at
the
factory.
If,
however,
it
is
found
necessary
to
readjust
the padding
condensers,
this procedure
must be followed
carefully. Do not
attempt
to
make
any
adjustments
until the procedure
is clearly
understood
or without
the
use
of a
good oscillator
or signal generator
and output
meter.
The Philco
Set
Tester 048 is highly
recommended
for this
procedure and
for all
service
work.
The
Receiver must be connected
to a
six-volt
storage
battery and turned on for operation.
It
is
assumed
that
tubes
have been checked
and
that the
Receiver
is
in
good condition except
for
the padding
adjustments.
Remove the
speaker
lid
from the
Receiver and
discon-
nect the antenna lead
from the Receiver.
Remove the
grid cap from the 6A7 tube
(for
location
see
Fig.2).
Set
up the
signal generator and adjust
it
to
exactly
260
K.
C.
Connect the generator lead
to
the
grid
cap of
the 647
tube.
(See
Irig.
2.)
The output
meter must
be
connected
by
means
of
an adapter
to
the small prong
of
-
the spealier
plug and
to
the
chassis.
The
Receiver
volume control must be turned on
to
approximately
full
volume
and the attenuator
in
the gen-
erator set
for a
half-scale reading
of
the
output
meter.
The
padders
@ and
@
are
adjusted
first
(Figs.
2
and
3.)
Turn
the adjustins
screw
@
all
the
way
in.
A
metal
screw
driver can
be used
for
this.
Then, with generator
attenuator set
so
there
is
approximately half-scale
read-
ing,
adjust the nut
@
with a fibre
wrench
for the
maxi-
mum reading
on the output
meter.
Then adjust the
screw
@
for
ma-rimum reading
on
the
meter. This adjustment is
critical.
Note the
maximum
reading obtainable
and
then
turn the
screw
in
again
and
readjust,
just
bringing the adjustment
up to
the maximum
reading. Do not
pass
it
and then
back
off.
Repeat
the
above procedure
with the
condensers
@
and
6r.
After
padding
the first
I.
F.
stage, remove
the
gen-
erator lead
from
the 6A7 tube and reconnect the grid
lead
to
the 6A7
tube.
Connect
the
antenna
lead
to
the
Re-
ceiver.
Set
the generator to
1500
K.
C. and then
connect
the generator lead to
the antenna lead.
There are four
holes
in line,
one
in
each
of
the
sections
of
the tuning
condenser
housing.
(See
Fig.
2.)
Place
a
nail of
the
size
that fits
snugly through the
holes and then
turn
the
condenser
plates out
of
mesh
until
they
strike
against the nail.
With
the tuning
condenser
in
this position adjust
the
Frc.
I
LOW FREQUENCY 9ADDER,