Emerson Keystone Figure 637, Service Manual

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Emerson Radio
LOW VQLTACE -
POWER SUPPLY
PICTURE CENTERING
LEVER (FOCUS COIL} -
WOBBLE PLATE
LEVER
, HI0H VOLTAGE
POWER SUPPLY
DEFLECTION YOKE
ON-OFF VOLUME
AND CONTRAST
AUDIO l-F
SECTION “
K IN E S C O P E
10 B P #
OR
I2 L P 4
VIDEO l-F
SECTION
VERTICAL HOLD
TU RRET
~ TUNER
B R IG H T N ESS -
AMD HORIZONTAL HOLD
SELECTO R AND
f i n e
T
u n i n g
r
Section 1.
GENERAL DESCRIPTION
1. FACILITIES— Emerson Models 614, 637, 644,
and 647 are wide-band video receivers, providing di-
rect-view high-definition p.ctures on ten or
tw e lv e-in ch
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 C O M P L E M E N T S: (Table 1).
N O T E : 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.
SYM BOL
TUBE
TYPE
F U N C T IO N
V I 6AG5
First video i-f amplifier
V 2 1 6A G 5
Second video i-f amplifier
V3 6A U 6
Third video i-f amplifier
V 4 6AL5 Video detector and AG C
V5 6A U 6
First video amplifier
V 6
12AU 7
Second video amplifier; second
sync amplifier
V 7
6A U 6 Sound i-f amplifier
V 8 6A U 6
Sound limiter
V 9
6T8 Sound disc, and audio amp.
V10 6V 6G T
Audio output
V l l
6SN 7G T Hor. phase invert.; horizontal
control (d.c. amp.)
V 12
6AL5
Hor. phase det. (sync disc.)
V13 6S N 7G T Hor. oscillator and discharge
V 14
6S N 7G T Vert, oscillator and discharge
V15 12AU 7 Sync sep. and d.c. restorer;
first sync, amplifier
V16 6K 6G T
Vertical output
V I 7 6BG6G
Horizontal output
V18 1B3GT High-voltage rectifier
V19
6 W 4 G T
Horizontal damper
V25
jlOBP4* or
112LP4 #
Kinescope
V 27 6J6
Oscillator and converter
V 28 6AG5 R-f amplifier
V 29 5U 4G
Low-voltage rectifier
* Chassis 120110B # Chassis 120113B
Figure l - l — Front View of Chassis 12011 OB
Scanned by mbear2k - Jan 20121/17