THOMSON V12 S1G User manual

THOMSON
Brandt
FERGUSON
SABA
TELEFUNKEN
THOMSON
VIDEO Ae | Oo =s2
SERVICE MANUAL
DOCUMENTATION TECHNIQUE
TECHNISCHE DOKUMENTATION Vi2
DOCUMENTAZIONE TECNICA
DOCUMENTACION TECNICA
Vi2 S1G VSH2050G
Vi2 S2G VSH2080G
THOMSON
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Ode : 351 028 80 - 1199 /4,8M - V12 S1/2G Print. wcooeranioun- ame
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GENERALS
POWER
POWER CONSUMPTION
DIMENSIONS
WEIGHT
FORMAT
MAX. RECORDING TIME
ACCESSORIES
VIDEO/AUDIO
SIGNAL SYSTEM
RECORDING SYSTEM
SIGNAL-TO-NOISE RATIO
HORIZONTAL RESOLUTION
FREQUENCY RANGE
INPUT/OUTPUT
TUNER/TIMER
TV CHANNEL STORAGE CAPACITY
TUNING SYSTEM
CHANNEL COVERAGE
AERIAL OUTPUT
MEMORY BACKUP TIME
SPECIFICATIONS
: AC 220 - 240 V~, 50/60 Hz
: Power ON : 24 W
Power OFF : 5,5 W
+ 400 (W) x 94 (H) x 347 (D) mm
: 4Kg
: S-VHS/VHS PAL Standard
: SP: 240 mn with E-240 video cassette
LP: 480 mn with E-240 video cassette
: RF cable, infrared remote control unit, “R6” battery x 2.
: PAL-type colour signal and CCIR monochrome signal, 625 lines 50 fields
: DA4 (Double Azimuth) head helical scan system
: 45dB
: 250 lines (VHS)
400 lines (S-VHS)
: 70 Hz to 10,000 Hz (Normal audio)
20 Hz to 20,000 Hz (Hi-Fi audio)
: 21-pin SCART connectors: IN/OUT x 1, IN/DECODER x 1
RCA connectors: VSH 2080 AUDIO IN/OUT x 1, VIDEO IN x 1
VSH 2050 AUDIO IN/OUT x 1
S-Video connectors: IN/OUT x 1
: 99 positions (+ AUX position)
: Frequency synthesized tuner
: VHF 47 - 89/104 - 300/302 - 470 MHz
UHF 470 - 862 MHz
: UHF channels 22 - 69 (Adjustable)
: VSH 2080 Approx. 60 mn.
VSH 2050 Approx. 10 mn.

34
3.1.1
3.1.2
3.1.3
3.2
3.24
3.2.2
3.3
3.3.1
3.3.2
3.3.3
3.3.4
3.3.5
3.3.6
3.3.7
3.4
3.4.1
3.5
3.5.1
3.6
3.6.1
44
4.2
43
44
45
46
47
Pages
ELECTRICAL ADJUSTMENT
PRECAUTION ...
Required test equipment
Required adjustment tools
Colour bar signal, colour bar pattern .
SERVO CIRCUIT
PB switching point
Slow tracking preset
VIDEO CIRCUIT...
EE Y level...
SP/LP REC colour level
PB Y level (S-VHS/VHS)
S-VHS VIDEO EQ
D/A level
Pilot burst level ....
Auto picture .....
AUDIO CIRCUIT.
REC FM level
SYSCON CIRCUIT...
Timer clock ......
ON SCREEN CIRCUIT.
Character position
CHARTS AND DIAGRAMS
NOTES OF SCHEMATIC DIAGRAM...
CIRCUIT BOARD NOTES...
BOARD INTERCONNECTIONS ...
VIDEO/N.AUDIO SCHEMATIC DIAGRAM .
ON SCREEN SCHEMATIC DIAGRAM .....
FMA SCHEMATIC DIAGRAM...
SYSTEM CONTROL.
SCHEMATIC DIAGRAM.
SWITCHING REGULATORs
SCHEMATIC DIAGRAM..
TUNER SCHEMATIC DIAGRAM
48
49
4.10
4.13
4.14
4.15
4.16
417
4.18
4.19
4.20
4.21
4.22
4.23
4.24
4.25
4.26
4.27
4.28
4.29
4.30
4.31
C.BOX CTL SCHEMATIC DIAGRAM......
TERMINAL (MAIN)
SCHEMATIC DIAGRAM
MAIN, A/C HEAD AND LOADING
MOTOR CIRCUIT BOARDS.....
3D SVHS(VIDEO)
SCHEMATIC DIAGRAM (VSH 2080) ....sascesse 33
2D SVHS(VIDEO)
SCHEMATIC DIAGRAM (VSH 2050)
2D SVHS(2D Y/C)
SCHEMATIC DIAGRAM (VSH 2050)
3D SVHS(3D/TBC)
SCHEMATIC DIAGRAM (VSH 2080)
2D SVHS CIRCUIT BOARD (VSH 2050)
3D SVHS CIRCUIT BOARD (VSH 2080)
TERMINAL SCHEMATIC DIAGRAM
TERMINAL CIRCUIT BOARD...
DEMODULATOR SCHEMATIC DIAGRAM..........53
DEMODULATOR CIRCUIT BOARD...
SWITCH/DISPLAY, REC SAFETY, JACK
AND JOG SCHEMATIC DIAGRAMS
SWITCH/DISPLAY, REC SAFETY, JACK
AND JOG CIRCUIT BOARDS...
FDP GRID ASSIGNMENT AND
ANODE CONNECTION (VSH 2080)
FDP GRID ASSIGNMENT AND
ANODE CONNECTION (VSH 2050)
VOLTAGE CHARTS (VSH 2080) .
VOLTAGE CHARTS (VSH 2050) .
SYSTEM CONTROL BLOCK DIAGRAM
VIDEO BLOCK DIAGRAM (VSH 2080)
VIDEO BLOCK DIAGRAM (VSH 2050)
AUDIO BLOCK DIAGRAM (VSH 2080)
AUDIO BLOCK DIAGRAM (VSH 2050)

~-SECTION 3 be
ELECTRICAL ADJUSTMENT - z
3.1 PRECAUTION
Electrical adjustment are required after replacing circuit com-
ponents and certain mechanical parts. It is important to per-
form these adjustments only after all repairs and replacements
have been completed. Aiso do not attempt these adjustments
unless the proper equipments is available. -
3.1.1 Required test equipment
@ Colour television or monitor
@ Oscilloscope: wide-band, dual-trace, triggered delayed
, Sweep
@ Frequency counter
@ Signal generator: RF/IF sweep/marker
© Signal generator: PAL colour bar, stairstep
© Recording tape (VHS tape/S-VHS tape)
@ Digit-key remote controller(provided)
3.1.2 Required adjustment tools
Alignment tape(SP) MHPE,
10405000
Presetting unit
76000899
Alignment tape
{S-VHS, SP/LP, colour bar)
MH-2H 76000840
‘See schematic diagram
Fig. 3-3-4 page 5
3.1.3 Colour bar signal,colour bar pattern
@ PAL colour bar signal
White(100%)
ecS
White(75%) 3 gi 8 5
58
| \ PAE s
o7V & Burst
w | /
} Ht 03V
03V i
v U
Horizontal vR-Y)
syne
U(B-Y)
Fig.3-1-1 PAL colour bar signal waveform
@ PAL colour bar pattern
@| =z «| #
=), S/s]-8]} 5/3) 8
—€/3;s)/8|
8/2]
2
> oO s
(75%) —t=
viu wis. Black
Fig.3-1-2 PAL colour bar pattern
3.2 SERVO CIRCUIT
Notes: + Uniess otherwise specified,all measurement
points and adjustment parts are located on the
MAIN BOARD.
+ Set the VCR to the mode A by the remote con-
troller.
Note:
The system control circuit of this model has
an automatic recognition about the ON-OFF
control of the DOCTOR SYSTEM.

3.2.1 PB switching point
Signal * Alignment tape [MHPE], Stairstep
V. syne
Measurement point |) * VIDEO OUT TERMINAL
Trigger slope (-) ©TP111(D.FF)
Adjustment tool *Presetting unit 76000899
8.0 + 0.5H [MHPE]
°7.5 + 0.5H [MHP}
Specification
Note:
+
Use
only
the
“E”
and
“F”
buttons,
depressing
other
buttons
during
adjustment
may
cause
ad-
justment
errors.
VSH
2080
(1)
Playback
the
stairstep
signal
of
the
alignment
tape
{MHPE]
;
(2)
Connect
an
oscilloscope
to
VIDEO
OUT
TERMINAL
and
TP111
(negative
slope),
and
then
observe
VIDEO
OUT
TERMINAL.
(3) Adjust by pressing the “E” or “F” buttons of the preset-
ting unit so that the switching point becomes 8.0 + 0.5H
from V.sync.
(4) Depress the STOP button.
(5)
Playback
the
stairstep
signal
of
the
alignment
tape[MHP].
(6) Adjust by pressing the “E" or “F” buttons of the preset-
ting unit so that the switching point becomes 7.5 + 0.5H
from V.sync.
(7) Depress the STOP button.
Note: + Use only the “O” button, depressing other but-
tons during adjustment may cause adjustment
errors. VSH 2050
(1)
Playback
the
stairstep
signal
of
the
alignment
tape
(2) Connect an oscilloscope to’ VIDEO OUT TERMINAL and
TP111 (negative slope}, and then observe VIDEO OUT
TERMINAL.
(3) Press the “O” button of.the presetting unit.
(4) The adjustment is performed automatically.
Once the adjustment is performed, the VCR will go into
the STOP mode.
(5) Playback the alignment tape again, confirm the switch-
ing point (See Fig. 3-2-2).
VSH 2050
VSH 2080
Fig. 3-2-1 Presetting unit
Switching point
* Alignment tape [MHP], Stairstep 8.0 + 0.5H (MHPE)
7.5 + 0.5H (MHP)
Mode PB
TBC : OFF
Equipment * Oscilloscope
V. rate
Fig. 3-2-2 PB switching point
3.2.2 Slow tracking preset
Signal Tuner or colour bar
Mode eSP/LP: REC + PB(SLOW)
°S-VHS
Equipment ¢TV-Monitor
Adjustment tool *Presetting unit 76000899
Specification Minimum noise
Note: - Use only the “B” and “C” buttons, depressing
other buttons during adjustment may cause ad-
justment errors.
(1) Record a colour bar signal in the SP mode.
(2) Playback the recorded signal on the FWD slow mode.
(3) Set the tracking control to the centre position by simul-
taneously pressing the CH “+” and “—” buttons.
(4) Observe the display on the TV monitor and adjust for op-
timum noise condition (best tracking) by depressing the
"B” or “C” buttons of the presetting unit.
(5) Depress the STOP button.
(6) Confirm that the bar noise is not visible on the TV moni-
tor in the slow mode
(7) Repeat steps (2) to (6) in the REV slow mode.
(8) Repeat steps (1) to {7) in the LP mode.
Fig. 3-2-3 Presetting unit

3.3 VIDEO CIRCUIT
Notes: - Unless otherwise specified,all measurement
points and adjustment parts are located on the
MAIN BOARD.
+ VIDEO circuit adjustments are performed by the
EVR system by use of the presetting unit and
digit-key remote controller.
+ S-INPUT means Y/C separated video signal in
the chart. :
+ Set the VCR to the mode A by the remote con-
troller.
+ Unless otherwise specified, set the VCR to the
following mode.
B OFF
PICTURE CONTROL || NORMAL
TBC ON |
Fig. 3-3-1 Presetting unit
FOP
EVR MODE
Fig. 3-3-2 EVR mode
3.3.1 EEY level
Signal * Colour bar
Mode oEE
Equipment * Oscilloscope
Measurement point |} *Y OUT TERMINAL
(75 ohm TERMINATION)
*Presetting unit 76000899
* Digit-key remote controller
eA:11
Adjustment tool
EVR mode
Specification *1.00 + 0.03 Vp-p (terminated)
(1) Connect an oscilloscope to Y OUT TERMINAL.
(2) Set the EVR mode by pressing the "K” button of the pre-
setting unit.
{3) Set “A: 11” by twice pressing 1 button of the remote
controller.
(4) Adjust the CH “+” or “~" buttons for 1.00 + 0.03 Vp-p.
(See Fig. 3-3-3.)
(5) Set the normal VCR mode by pressing the “K" button
of the presetting unit again so adjustment data is memo-
rized.
Ly
qo
[
20 mV/div H. rate
{
| 1.00 + 0.03 Vp-p
20 usec
Fig. 3-3-3 EE Y level

3.3.2 SP/LP REC colour level
x 150 + 5%(SP)
Measurement point |} ¢PB COLOUR
eTP111 (D.FF)
*Presetting unit 76000899
* Digit-key remote controller
© LPF fixture
Trigger slope (-)
Adjustment tool
EVR mode °A:2
°"B" x 150 + 5% : SP
"BY x 110+ 5% : LP
Specification
Signal Alignment tape [MH-2H]
Colour bar
Mode °PB ut
REC — PB: SP/LP
¢S-VHS
Equipment * Oscilloscope
“Bx 110 + 5%(LP)
5 mVidiv. V. rate 2 msec
Fig. 3-3-5 REC colour level
3.3.3 PB Y levei (S-VHS/VHS)
Signal * Colour bar
Mode REC ~ PB: SP
© S-VHS/VHS,
Equipment * Oscilloscope
1kQ 30pH 180 pH
Vv. PB FM
from TP106 PB COLOUR
[ MAIN board ] (629 kHz)
120 pF 7 180 pF
Fig. 3-3-4 LPF
(1) Connect an oscilloscope to PB COLOUR of a LPF (refer
to Fig. 3-3-4) and TP111 (negative slope) on the MAIN
board.
(2) Playback the SP colour bar signal of the MH-2H alignment
tape.
(3) Adjust by pressing the CH “+” or “-" buttons of the
Front panel for maximum level of the color waveform and
make a note of the higher colour level “B”.
(4) Press the STOP/EJECT button and eject the MH-2H align-
ment tape.
(5) Set the EVR mode by pressing the “K” button of the pre-
setting unit.
(6) Set “A: 2” by pressing 2 button of the remote control-
ler.
(7) Before recording, adjust the CH “+” or “—" buttons of
the remote controller so that the higher level channel! be-
comes 150 + 5% : SP (110 + 5% : LP) of the‘note “B”
level during playback as shown in Fig. 3-3-5.
(8) Record a colour bar signal in the SP (LP) mode, and play-
back the recorded colour bar signal.
(9) Set the normal VCR mode by pressing the “K” button
again so adjustment data is memorized. =
Measurement point |] *Y OUT TERMINAL.
(75 ohm TERMINATION)
¢Presetting unit 76000899
* Digit-key remote controller
eAl
Adjustment tool
EVR mode
Specification 1.00 + 0.03 Vp-p (terminated)
(1) Connect an oscilloscope to Y OUT TERMINAL.
(2) Set the EVR mode by pressing the “K" button of the pre-
setting unit.
(3) Set “A: 11” by twice pressing 1 button of the remote
controller. :
(4) Record a colour bar signal in the S-VHS mode, and play-
back the recorded colour bar signal.
(5) Adjust the CH “+” or “—" buttons for 1.00 + 0.03 Vp-p
as shown in Fig. 3-3-6.
(6) Set the normal VCR mode by pressing the “K” button
of the presetting unit again so adjustment data is memo-
rized.
(7) Repeat steps (1) to (6) in the VHS mode.
| 1.00 + 0.03 Vp-p
20 mVidiv H. rate 20 psec
Fig. 3-3-6 PB Y level

3.3.4 S-VHS VIDEO EQ 3.3.5 D/A level
Signal © S INPUT Signal Colour bar
*Video sweep
Mode eEE
Mode REC — PB : SP/LP *S.VHS
*S-VHS 5 SOc
Picture control REC : Normal _ quipment ecMoscore.
c PB: Edit Measurement point || ¢CN1003-3 pin (Y OUT)
Equipment * Oscilloscope [sB.ob20:SVES poard]
Measurement point |} ¢ Y OUT TERMINAL
(75 ohm TERMINATION)
Trigger slope (-) °TP111 (D.FF)
Adjustment tool Presetting unit 76000899
* Digit-key remote controller
EVR mode 2A:3
Specification °3.6 + 0.4 scale: SP
°3.2 + 0.4 scale: LP
(1) Connect an oscilloscope to YOUT TERMINAL and TP111
(negative slope).
(2) Record a video sweep signal in the S-VHS SP mode, then
play it back.
(3) Set the EVR mode by pressing the “K" button of the pre-
setting unit.
(4) Set “A: 3” by pressing 3 button of the remote control-
ler.
(5) When assuming the 100 KHz sweep signal marker on
the bigger channel is four scales on the oscilloscope, ad-
just the CH “+” or “—" buttons on-the front panel or the
Digit-key remote controller so that the 3 MHz is set at
3.6 + 0.4 scale (-1 + 1.0 dB) while observing Y OUT of
the S output. (See Fig. 3-3-7.)
(6) Set the normal VCR mode by pressing the "K” button
of the presetting unit again so adjustment data is memo-
rized.
(7) Carry out the step (3) and (4) in the S-VHS LP mode.
(8) When assuming the 100 kHz sweep signal marker on the
bigger channel is four scales on the oscilloscope, adjust
the CH “+" or “-" buttons on the front panel or the Digit-
key remote controller so that the 3 MHz is set at 3.2 +
0.4 scale (-2 + 1.0 dB) while observing Y OUT of the S
output. (See Fig. 3-3-7.)
Four scale
100.KHz + MHZ 9 patie
3 MHz
| 5 MHz
Lu
a 1
V. rate
SP :3.6 + 0.4 div.
LP :3.2+0.4 div.
Fig. 3-3-7 S-VHS VIDEO EQ
Adjustment part °VR 1201 (D/A LEVEL) VSH 2050
VR 1401 (D/A LEVEL) VSH 2080
Specification (NOTE)}] 2.05 Vp-p (REFERENCE VALUE}
a
Connect the oscilloscope to the CN1003-3 pin(Y OUT)
3D SVHS or 2D SVHS board.
(2) Confirm the Y level value during external S input.
(3) Switch the input signal to the external input, then adjust
the VR 1401 on the 3D SVHS board or the VR 1201 on
the 2D SVHS board so that the Y level value becomes
the same level value witch was confirmed at the step (2).
Note: ¢ The adjusted value of 2.05 Vp-p is a reference
value which should be obtained during external
S input. The value should be adjusted to the one
which was confirmed at step (2).
|
i 1
|
NM j H
| H 2.05 Vp-p
- (relerence vaiue)
)
50 mV/div H. rate 20 psec
Fig. 3-3-8 D/A LEVEL
3.3.6 Pilot burst level
Signal © Colour bar
Mode °EE
°S-VHS
Equipment * Oscilloscope
Measurement point |} «TP1001 (FSC PHASE)
[3D or 2D SVHS board]
¢VR1002 (P. BURST LEVEL)
{3D or 2D SVHS board]
°"B" x 110 + 10%
Adjustment part
Specification
(1) Connect the oscilloscope to the TP1001 (FSC PHASE)
on the 3D or 2D SVHS board.
(2) Load an S-VHS tape then set the unit to the S-VHS EE
mode.
(3) Adjust the VR 1002 of the 3D or 2D SVHS so that the
pilot burst level becomes "B" x 110 + 10% against the
value of the burst level "B".

“BPX 110:£10% age
|
3.4 AUDIO CIRCUIT
Notes: + Uniess otherwise specified, alli measurement
point and adjustment parts are located on the
MAIN BOARD.
« This adjustment should be done after the video
circuit SP and LP REC colour level are adjusted.
+ GND{Ground) should be taken from the tuner
board shield.
3.4.1. REC FM level
Fig. 3-3-9 PILOT BURST LEVEL
3.3.7 Auto picture
*#AUX
*VIDEO : Colour bar
* AUDIO : No signal
*REC > PB: LP
*S-VHS
Signal
Mode
Signal *Monoscope
Mode * REC > PB: SP/LP
*SVHS:
Adjustment tool ¢Presetting unit 76000899
Specification *STOP mode
°B.E.S.T : OFF
Equipment
* Oscilloscope
Measurement point
©TP2253 (A. PB FM)
Trigger slope ( -)
TP111 (D. FF)
(1) Record a monoscope signal in the SP mode.
(2) Playback the recorded signal.
(3) Press the “L" button of the presetting unit during play-
back.
(4) Confirm that the VCR will go into the STOP mode.
(5) Repeat steps (2) to (4) in the LP mode.
Fig. 3-3-10 Presetting unit
*VR2251 (A. REC. FM)
*600 + 100 mVp-p
Adjustment part
Specification
(1) Connect an oscilloscope to TP2253.
(2) Record-a colour bar signal without an audio signal in the
S-VHS LP mode’ then playback.
(3) Adjust VR2251 for 600 + 100 mVp-p playback level of
higher channel level before recording.
(4) Confirm that the lower channel level is more than 450
mVp-p.
1 i
More than | 600 + 100
450 mVp-p mVp-p
i i
50 mV/div V. rate 20 usec
Fig. 3-4-1 Audio REC FM level

3.5 SYSCON CIRCUIT
Notes: + Unless otherwise specified,all measurement
points and adjustment parts are located on the
MAIN BOARD.
* When perform this adjustment,remove the
MECHANISM assembly.
3.5.1. Timer clock
Signal No signal
Mode eEE
Equipment *® Frequency counter
© 1C3001-PIN61
© C3025 (TIMER CLOCK)
© 1024.008 + 0.001 Hz
{976.5549 + 0.0010 psec.]
Measurement point
Adjustment part
Specification
(1) Connect the frequency counter to 1C3001-PIN61.
{2) Connect the short wire between 1C3001-PIN24 and
Vec(5V).
{3) Short the leads of capacitor C3026 once in order. to re-
set (C3001.
(4) Disconnect the short-wire between |C3001-PIN24 and
Vec then connect it again.
(5) Adjust C3025 trimmer capacitor so that the output from
1C3001-PIN61 falis within 1024.008 + 0.001 Hz (976.5549
+ 0.0010 psec.) range. :
3.6 ON SCREEN CIRCUIT @
Note: ¢ Set the VCR to the mode A by the remote con-
troller.
3.6.1 Character position
Signal No signal
Mode i@EE
Equipment *TV-monitor
Adjustment tool *Presetting unit 76000899
* Digit-key remote controller
Specification «Character centre
Note: ¢ Use only the “H” button, depressing other but-
tons during adjustment may cause adjustment
errors.
(1) Press the MENU button and display the on screen char- 6
acter.
(2) Observe the TV-monitor and centre position of charac-
ter by pressing the “H” button of the presetting unit
Fig. 3-6-1 Presetting unit
ee