Philco 816 Service Manual

PHILCO
TRANSITONE
,SERVICE
B
ROADCAST
JANUARY,
1936
MODEL
816
RECEIVER
fflHE
Prlrr,co Transitone Model
81'6
is
Philco's newest automobile
radio. It is a
highly
developed superheterodyne single-unit
I typ"
Receiver
with all
the outstanding features required
in
such
a fine
instrument.
THE NEW RECEIVDR IS EQUIPPED WITH AN ADJUSTABLE ANTENNA
STAGE,
WHICI{ MAKES IT
FOS-
SIBLE TO
O,PERATE
THE
RECEIVER AT MAXIMUM EFFICIENCY ON
ANY
ROOF-TYPE OR UNDER-CAR
TYPE
ANTENNA.
The Receiver, speaker
and full-wave
Prrrr-co
Vibrator are housed
in a
rugged,
compact,
fully
shielded
container, which
is
designed
for
quick and
easy
installation on the dash
of
all
automobiles. When installed
in
the car, the
loud
speaker faces
the front
seat, so
that the
extremely
pon'erful
Prrrr,co electro-dynamic speaker, concealed behind an
artistic grille,
delivers
its
full-toned
reproduction toward the
occupants
of
the car
with
utmost ficlelity.
All
tubes used
are the latest
Prlr.co
high-efriciency tubes, dilsigned especially
for
automobile
radio.
i i'
Prrrr,co's system
of
automatic volume control
used
in this
Receiver
not only
gives
that
smooth, elastic control which
counter-
acts
fading while
driving
along and prevents
blasting
of
local
stations,
but
also
subdues
the harsh interference usually
present
between stations.
The new Receiver
is AL'L-ELECTRIC,
operating entirely
from
the car
battery
system. The full-wave Prrrrco
Vibrator
is
built
in
as
an integral
part of
the
Receiver.
Interference filters
to
cut out the motor interference
set
up
by
the car ignition
system and specially
designed shielding
make
the
Receivers especially easy
to
install.
The
Model 816
Receiver
is
furnished
with
the new streamline "wide vision" control which can be installed on
the
edge
of
the
instrument
board. This control
unit is
exceptionaly attractive and
is
designed
to
blend harmoniously'n'ith the
instrument
boards
of
practically aII
cars.
The
circuit and layout
of
the
Models 8168-8fGC
and
8l6P
Receivers
are the
same
as the
Model
816.
However, these Receivers
are
equipped
with
a
special ''customed"
control
unit
which
matches
the instrument board fittings,
and
is
designed
for
installation
in
the
space
provided
for
radio control
in
the instrument board of the
1936
Buick,
Chevrolet
and
Pontiac
cars.
I.
F.
TRANSFORMERS
AND
PADDERS
The
L F.
transformers are
assembled
complete
with
pad-
ding
condensers.
Both the primary
and
the secondary padderg are
placed
side
by side.in the top of
the transformer shield
can.
The
adjusting screws are accessible
thru the
holes
in
the top
of
the shield. (See
Figure 2).
The coil'windings terminate
in
Ieads instead
of
terminals
or lugs.
The color
scheme
of
the leads
is
given
in
Figure
I.
GR,ID
GROUND
PLATE
0+
Frcunr
I
If
replacements
are ever necessary,
replac_e
the entire
coil
assembly-, 32-1928
for the
first
I. F.
stage and
32-1929
for
the
second
i. F.
stage. Neither the
coil nor the
padders
will
be
furnished
separalely. Order only
by
the
above
numbers.
MODEL
816
ADJUSTMEI\TS
All
padding adjustments are
carefully
made
at
th_e_factory
and
or-dinarily
no
readjustments
are
necessary. However,
when readjustments are required,
the
procedure
given
below
must be followed
in
detail.
Equipment
Fully
charge heavy
duty
storage
battery
or
6-volt
power
pack,
O48A
Philco Set Tester,
3164,
Padding wrench,
27-7159
Padding screw driver.
General
OUTPUT
METER-The
output meter must be
connected
b;r means
of
an adapter
to
the
plate of the type
41
output
tube and
to
the Receiver
chassis.
SIGNAL GENERATOR-WiIh the
Receiver
and
signal
generator
set
up for
operation
at
the
prescribed frequency,
turn the
Receiver volume
control on
full
and set
the
signal
^
.generator
attenuator so
that a half
scale reading
is
obtained
'
on
the output
meter. The
signal
in
the
speaker should
be
-
audible
but not
loud.
The shielding on
the
signal generator
output
lead must
be
-.
connected
to
the
Receiver
housing.
Proced.ure
I. F.-Set the
signal generator
at
exactly 260
K.
C.
Connect
the
generator
lead
to
the grid cap
of
the
78
L
F.
Frcrrnn
2
tube (without
removing the
grid
cap)
in
series
with
a
.1
mfd.
condenser.
Adjust
the
secondary screw
padder @
on
the
second
L
F.
transformer for
maximum reading on the output meter.
Then
adjust the primary
screw
padder 6b
for
maximum
reading.
(See
Figure
2 for
location
of
padders).
Remove
the
generator lead
from
the
78
tube.
Connect
the generator lead
to
the
grid
cap
of
the 6A7
tube
(without
removing
the
grid cap) in
series
with a .t
mfd.
condenser.
Adjust
the
secondary screw
padder @ on the first
I. F.
transformer
for
maximum reading on the output
rneter.
lhen adjust
the
primary
screw
padder
@
for
maximurn read-
irg.
(See
Figure
2 for
location
of
padders).
HITGH
FREQUENCY
AND R. F.-After
padding
the
first
I.
F.
stage remove
the generator lead from the
6.47
tube.
Set the
signal
generator
at
1550
K.
C. and then
connect
the generator lead to the
grid
cap
of
the 78
R. F. tube (with-
out
removing the
grid
cap)
in
series
with
a
.1
mfd.
condenser.
Turn the tuning
condenser
plates
out of
mesh as
far
as
they
will
go.
With the tuning
condenser
in
this position,
ad.iust
the high
frequency
padder
@
and the
R. F.
padder @ until
ANTENNA
SOCKET