Sharp 20LK31M Service Manual Download

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20LK31M
20LK61M

COLOR TELEVISION

Chassis No. SN-70A

In the interests of user-safety (Required by safety regulations in some countries) the set should be restored to its
original condition and only parts identical to those specified should be used.

S80G420LK31M/

ELECTRICAL SPECIFICATIONS ......................................................................................................... 1

IMPORTANT SERVICE SAFETY PRECAUTION ................................................................................ 2

LOCATION OF USER'S CONTROL ..................................................................................................... 4

INSTALLATION AND SERVICE INSTRUCTIONS ............................................................................... 5

CHASSIS LAYOUT ............................................................................................................................. 10

BLOCK DIAGRAM .............................................................................................................................. 12

SCHEMATIC DIAGRAMS ................................................................................................................... 14

PRINTED WIRING BOARD ASSEMBLIES ........................................................................................ 21

REPLACEMENT PARTS LIST ........................................................................................................... 24

PACKING OF THE SET ...................................................................................................................... 31

Page

CONTENTS

ELECTRICAL SPECIFICATIONS

Specifications are subject to change without
prior notice.

SERVICE MANUAL

20LK31M
20LK61M

SHARP CORPORATION

MODELS

20LK61M

20LK31M

POWER INPUT ........................................ 110-220 V AC 50/60 Hz
POWER RATING

20LK31M ............................................................................ 88 W
20LK61M ............................................................................ 98 W

PICTURE SIZE .......................................... 1,194cm

(185sq inch)

CONVERGENCE ............................................................ Magnetic
SWEEP DEFLECTION .................................................... Magnetic
FOCUS .............................................. Hi-Bi-Potential Electrostatic
INTERMEDIATE FREQUENCIES

Picture IF Carrier Frequency .................................... 45.75 MHz
Sound IF Carrier Frequency ..................................... 41.25 MHz
Color Sub-Carrier Frequency ................................... 42.17 MHz

(Nominal)

AUDIO POWER

OUTPUT RATING
20LK31M ........................................... 1.5W (at 10% distortion)
20LK61M ........................................... 3.0W (at 10% distortion)

SPEAKER

SIZE ........................................................................ 9 cm

5 cm

VOICE COIL IMPEDANCE
20LK31M ................................................... 16 ohm at 400 Hz
20LK61M ................................................... 32 ohm at 400 Hz

ANTENNA INPUT IMPEDANCE

VHF/UHF ................................................... 75 ohm Unbalanced

TUNING RANGES

VHF-Channels ............................................................. 2 thru 13
UHF-Channels ........................................................... 14 thru 69
CATV Channels ......................................................... 1 thru 125