Service manual
Emerson
Radio
Section
1.
GENERAL
DESCRIPTION
1.
FACILITIES—Emerson
Models
614, 637, 644,
and 647 are
wide-band video receivers, providing
di-
reci-view
high-definition
pictures
on ten or
twelve-inch
electro-magnetic deflection kinescopes.
All
models
in-
corporate several design features including intercarrier
sound,
AFC in the
horizontal sync circuits, automatic
gain
control,
a
series-type transformer power supply,
and
internal antennas.
Models
614 and 637
employ Chassis
120110B;
Models
644 and 647 use
Chassis
120113B.
Both chassis
are
basically
alike;
the
latter
is
modified
to
accommo-
date
the
larger kinescope, type
12LP4
or
12QP4.
Model
614 is
housed
in a
plastic cabinet,
and
Model
637 is
contained
in a
wooden
cabinet;
both
are
table
model
receivers using
a
type
10BP4
picture tube.
Model
644 is
housed
in a
table model
cabinet;
Model
647
uses
a
consolette-type
of
cabinet.
2.
SPECIFICATIONS—
a.
TUBE
COMPLEMENTS:
(Table
1).
NOT!1":
The
tube
complements
of
both chassis
are
alike, except
for the
kinescope. Chassis
120113B
uses type
12LP4
kinescope;
some chassis
may be
equipped
with
a
type
12QP4.
SYMBOL
Vl
V2
V3
V4
V5
V6
V7
V8
V9
V10
Vll
V12
V13
V14
V15
V16
V17
V18
V19
V25
V27
V28
V29
TT
TRP
1
.
I
M
-
TYPE
6AG5
6AG5
6AU6
6AL5
6AU6
12AU7
6AU6
6AU6
6T8
6V6GT
6SN7GT
6AL5
6SN7GT
6SN7GT
12AU7
6K6GT
6BG6G
1B3GT
6W4GT
)
10BP4*
or
112LP4#
6J6
6AG5
FUNCTION
First
video
i-f
amplifier
Second video
i-f
amplifier
Third
video
i-f
amplifier
Video
detector
and AGC
First
video
amplifier
Second video
amplifier;
second
sync
amplifier
Sound
i-f
amplifier
Sound
limiter
Sound
disc,
and
audio amp.
Audio
output
Hor. phase
invert.;
horizontal
control (d.c. amp.)
Hor. phase det.
(sync
disc.)
Hor. oscillator
and
discharge
Vert,
oscillator
and
discharge
Sync
sep.
and
d.c. restorer;
first
sync,
amplifier
Vertical
output
Horizontal
output
High-voltage
rectifier
Horizontal damper
Kinescope
Oscillator
and
converter
R-f
amplifier
5U4G
Low-
voltage
rectifier
*
Chassis
120110B
#
Chassis
120113B
WOBBLE
PLATE
LEVER
LOW
VOLTAGE
POWER
SUPPLY
PICTURE
CENTERING
LEVER
(FOCUS
COII
DEFLECTION
YOKE
C-2l,C-39,C-4l,C-74
HIGH
VOLTAGE
POWER
SUPPLY
ON-OFF
VOLUME
AND
CONTRAST
AUDIO
I-
SECTION
C-36.C-49
C-75
VERTICAL
HOLD
BRIGHTNESS
AND
HORIZONTAL
HOLD
VIDEO
I-F
SECTION
TURRET
TUNER
SELECTOR
AND
FINE
TUNING
Figude
1-1—Front
View
of
Chassis
120110B