Teac CT M141 Service Manual

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TEACQ

CT-M141

Colour Television

SERVICE MANUAL

Thanks for buying a TEAC. Read this manual carefully
to get the best performance from your new TEAC Col~
our Teievision.

KOYO ART PRINTING-PHOTO TYPE

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CONTENTS

Contents and Specifications ........
Safety Precautions ......
Servicing Precautions
Controls Location ........
Disassembly Instructions
Parts Location Diagram of Main Chasers ..
Adjustment Instructions . ..... 9
Circuit Description ..... 14
Troubleshooting Guide ..... 19
Block Diagram
Wiring Diagram .....
Terminal View of Semiconductor ..

Exploded View ...... '
Printed Circuit Board
Component Location Guide
Replacement Parts List .........
Memo .................
Circuit Diagram ..

SPECIFICATIONS

Power Consumption ......
Receiving TV System .

................................................................................ 70W
............................................................... CCIR Standard

COLOUR RECEIVING SYSTEM PAL/SECAMB/G PAL B/G- PAL-i PAL-H
SECAM D/K
Intermediate _ _ __Pictu_re _____ g8_._9_Ml-lz_ _ _ _3_8.9 MBA _ £9.53 MHZ- __ 38.9_MHZ
Frequency _ _ _So_un_d _____ ago/I142. _ _ 215 MHz _ jail/Ida _ sé-tMt'L:
Colour 34 47 MHz 33.57 MHz 35 07 MHz 34.47 MHz
Receiving _ _v_H£ 5°! _ -2: 9H5: _ e L lieu _ _ _N_0uE_ _ _ 2-§ 9H. _
Channel _ VHF High-I 5-12 CH, 82-825 6-12 CH NONE 5A-11 CH
"UHF 21-69C3_H__ "21-7390T-i 51-696H"21-696H
Power Source 220V/50Hz (SMPS) 240VI50H2 (SMPS)

Tuning .........................................................................................
Audio Output .....................
Antenna lnput Impedance .

. Voltage Synthesizer
............. MAX. 4W
75 ohm IEC Type
(300 ohm using balun supplied)
A34KC012XX

Picture Tube .........................................................................

Speaker ........... 92 x 92 mm
Dimension .. . 360(W) x 370(0) x 349(H) mm
Weight ............................................................................................................... 10.4 Kg

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Pin Function Chart of lC101 (GL3120AILA7520)

. Pin No. Description
1, 30 FM detector, pin 1 and 30, uses the quadrature detection circuit.
After the signal, with its amplitude limited by the limit Amp, is output from pin 1 and 90° shifted by the
phase shifter, it is input at pin 30.
2 Quadrature detected signal is output at pin 2 through emitter follower.
3 DC VR input terminal pin 3 attenuates the audio signal.
4 The sound Amp. NFB (Negative Feed-back) terminal.
5 The sound output terminal.
6 The ground terminal, and is connected to the ground of the SAW filter.
7, 14 [F AGC Filter terminals (PIN 7), RF AGC Filter terminal (PIN 14).
Pin 7 is also used as the video and audio mute terminal.
8, 11 Bypass AC signal contained in VlF Amp signal.
i7
9, 10 VlF input terminals.
12 The RF AGC VR (Variable Resistor) terminal.
VR101 is connected as the RF AGC VFi.
. 13 The output of RF AGC. When the RF AGC voltage is below 9 V,
R102 and R103 divide the Resistance and C104 is necessary to stop the oscillator.
15, 16
17 The AFT DC voltage from pin 17 is varied by R126 and R127.
18, 21 AFT circuit is the quadrature detection circuit and is connected between the pin 18 and pin 21.
19. 20 The carrier element is taken out from the LC tank circuit through pins 19 and 20.
h
22 The video ouptut terminal.
23, 24 These are the supply voltage input terminals.
Pin 23 = VIF block
Pin 24 = SlF block
25 The SIP primary detection output terminal.
26. 27, 28 Pins 28 and 28 are by-pass ground terminals,
Pin 27 is the unbalanced input terminal.
9
29

l

The mute & sound volume control terminal.