Toshiba MM20E45 Installation guide

COLOUR TELEVISION
MM20E45
TECHNICAL TRAINING MANUAL
FILE NO.016-9502
N5MM1 Chassis

CONTENTS
SECTION I
OUTLINE
SECTION II
CHANNEL SELECTION CIRCUIT
SECTION III
RGB SIGNAL PROCESSING CIRCUIT
SECTION IV
CRT DRIVE CIRCUIT
SECTION V
MODE DISCRIMINATING CIRCUIT AND SYNC SIGNAL PROCESSING CIRCUIT
SECTION VI
SYNC SEPARATION CIRCUIT OF TV MODE
SECTION VII
HORIZONTAL AND VERTICAL OSCILLATION CIRCUIT
SECTION VIII
VERTICAL DEFLECTION CIRCUIT
SECTION IX
HORIZONTAL DEFLECTION CIRCUIT
SECTION X
PROTECTION CIRCUIT
SECTION XI
OSD STABILIZATION CIRCUIT
SECTION XII
PICTURE TUBE
SECTION XIII
POWER SUPPLY CIRCUIT
SECTION XIV
FAILURE DIAGNOSIS PROCEDURES

1-1
SECTION I OUTLINE
1. OUTLINE OF N5MM1 CHASSIS
(MM20E45)
Thismodelisa20”colorTVwith181channeltunerandbuilt
in VGA and Mac II capability. The hybrid design of this
model allows it to serve several purposes. Television
reception, a monitor running Multimedia, PC applications,
or for playback of video games. The 20” FST picture tube
features a stripe pitch 0.58mm, providing a favourable
comparisonstoconventionaldesignswhichgenerallymeasure
0.75 to 0.9mm.
2. PC BOARD CONFIGURATION
(1) Power/V.C.D. PB5226
PB5226-1 Power
PB5226-2 V.C.D.
(2) Deflection PB5227
(3) Signal/Video PB5228
PB5228-1 Signal
PB5228-2 Video
PB5228-3 D-SUB

1-2
3. CONSTRUCTION OF CHASSIS
Power unit
Converter trans
Converter trans
Stand by trans
Sound out radiator
V out radiator
Choke coils
Choke trnas
H out radiator
Signal unit
Jack board
S-VIDEO
Tuner
Video unit
D-sub unit
D-sub connector
Front keys
Power LED
Remote control
receiver
Flyback trans
Def unit
V/C/D unit
Rectifier
Power radiator

1-3
4. LOCATION OF CONTROLS
4-1 TV Set
RGB/
TV/VIDEO
button
MENU button
ADV button
VOLUME
CHANNEL
POWER indicator
REMOTE senser
POWER button

1-4
4-2 Remote Control
ThisRemoteControlallowsyoutocontrolthefunctionsofyourTVsetfrom16feet(5m)away.The“*”markedfunctionbuttons
do not have duplicate locations on your TV set. They can be controlled only by the Remote Control.
Aim at the TV set
TIMER button*
Channel Number
buttons*
CH RTN (Channel Return)
button*
MTS button*
POWER button
MUTE button
SET UP button*
-/+ buttons
OPTION button*
RESET button*
PIC (Picture)* button
T
V/VIDEO button
RECALL button*
AUD (Audio) button*
CHANNEL button
s
VOLUME buttons

1-5
4-3 Monitor Panel
This TV set is equipped with RGB INPUT connector, RGB AUDIO INPUT jacks, S-VIDEO INPUT jack, VIDEO/AUDIO
INPUT jacks and VARIABLE AUDIO OUTPUT jacks of connecting your desired personal computer and video/audio
equipment.
TV Rear
34251
RGB INPUT Connector – provide for direct connection of a personal computer.
RGB AUDIO INPUT Jacks – provide for direct connection of a personal computer with audio output terminals.
S-VIDEO INPUT Jack – provide for direct S-video connection from an S VHS VCR or a video disc player.
VIDEO/AUDIOINPUTJacks–providefordirectconnectionofvideodevices(VCR,videodiscplayer,camcorder,etc.)
with video/audio outputs.
VARIABLE AUDIO OUTPUT Jacks – feed volume-controlled stereo audio out from whatever displayed on the screen,
allows connection of audio amplifier and lets you adjust sound level with TV’s remote.

1-6
5. MM20E45 BLOCK DIAGRAM
Tuner/IF module
20VMMTV BLOCK DIAGRAM
Signal switching
TC4053BP
Audio control
CXA1774S
Micro-computer
Memory
Band pass
Audio output
TA8200AH
C. CAP slicer
Synchronizing signal process M52346SP
Signal switching
TA7730
R-output
Vertical output
LA7837
Horizontal drive Horizontal
output
Mode distinction TA75339AP TC74HC86AP TC4514P TA75902 Horizontal/vertical
oscillation LA7860
S-shape capacitor switching
Linear coil switching
Resonance
capacitor
switching
Drive
switching
Synchronizing
signal switching
TC40538P
F/V conversion
IR9331 Horizontal amplitude
control chopper Horizontal drive Horizontal
output
Power unit
To be added for MM
Model change
( ) For MM
RGB
RF VIDEO
L
R
D.L
Signal
switching
AN5862K
Resonance
capacitor
switching
L
R
V/C/D
TA8801
OSD
R G B
R G B
R-Y G-Y B-Y -Y
EH
G-output B-output
VAR. OUT
FBT
VIDEO
(VERT)
(+15V)
(HEATER)
DAC
DPC
TA8859AP
HEATER
+15V AUDIO VERT.
+100V
TV & MM
H.Sync V.Sync Syncon G
High voltage
control chopper
Drive
switching
L
R
H V

1-7
6. SPECIFICATIONS
SPECIFICATIONS MODEL No. MM20E45
GENERAL
1 Picture Tube D/T Invar
2 Channel Capacity 181ch
3 C. Caption
4 MTS with dbx
5 Bass, Treble, Balance
6 Sub Audio Program
7 Remote hand unit Regu.
8 Nbr of RMT Button 29key
9 LED Indicators (P)
10 Local Keys 8key
11 Front Surround –
12 Sub Bass System
13 Audio Output 5W x 2
14 Speaker Size & Nbr 80 x 120 x 2
15 Comb Filter (GLS)
16 Black Level Expand –
17 Horizontal Resolution 500
18 Parental-Ch Lock
19 Channel Caption –
20 Off Timer (180min)
21 Channel Search –
22 S-Video In-Term (1)
23 Audio, Video In-Term (1)
24 Variable Audio Out (RCA Jack)
25 RGB Audio (L, R)
26 Mini D-Sub 15pin
27 Rod-Ant/Adapter –/–
NEW
SOUND
PICTURE
OTHER
CABINET
TERM

1-8
MM20E45 PC BOARD CONSTRUCTION
ITEM MM20E45 NEW MODEL CIRCUIT NOTE
DEF
PB5227
POWER/VCD
PB5226
SIGNAL/
VIDEO
PB5228
Def.
PB5227
(249.0 x 330.0)
Power/Audio
PB5226-1
(153.0 x 317.0)
Video/Chroma/Def
PB5226-2
(96.0 x 160.0)
Signal
PB5228-1
(110.0 x 330.0)
Video (CRT/D)
PB5228-2
(119.0 x 210.0)
D-Sub
PB5228-3
(28.5 x 41.5)
Printed wiring board
part code
P/P-M/P:
23534680B
Printed wiring board
part code
P/P-M/P:
23534679B
Printed wiring board
part code
P/P: 23534681B
M/P: 23534681C
249 x 330
dro
p
Hole draw-
ing: New Hole drawing: New
249 x 330
Hole drawing: New
249 x 330
Hole drawing: New
SIGNAL
VIDEO
V
-
CUT LINE
drop
D-SUB
Hole draw-
ing: New
POWER
V-CUT LINE
V/C/D
drop
Hole draw-
ing: New