Sanyo C20VTI I-M User manual

SERVICE MANUAL Colour Television with
=1’1’yo
FILE NO
Model NO. C20VTI I-M@
Videocassette Recorder (New Zealand /Oceania)
Service Ref. No. C20VT11 -M@-00
w
t,
;
Contents
Safety Precautions, X-Radiation Precautions ................. ~
Specifications .....................................................................
1. Mechanical Disassembles
1-1. Cabinet back removal ............................................ 4
1-2. Chassis removal .................................................... 4
1-3. Video mechanism removal .................................... 5
1-4. Service procedure ................................................. 7
1-5. Replacement of the reel drive belt ........................ 8
1-6. Video mechanism disassemblies .......................... 8
1-7. Cassette mechanism assembly .............................11
2, Service Mode ................................................................l2
3. Power Circuit Protection and
Self Diagnosis Display
3-1. Power circuit protection ........................................ 13
3-2. Power circuit problem self diagnosis .................... 13
3-3. VCR self diagnosis ................................................l4
4. ICS Pin Description
4-1. IC800 (CPU) pin description .................................15
4-2. IC1930 (DAC) pin description., .............................l5
5. Service Adjustments (TV Section)
+15V/+1 15V, Vertical size/center, Focus adjustment..l 6
Grey scale, AGC, Horizontal center adjustment .........l7
Horizontal width adjustment, High voltage check ........18
Clock frequency confirmation .......................................l8
6. WF Adjustment ............................................................. 19
7. A7TAdjustment ............................................................2O
8. Purity and Convergence Adjustment ...........................21
Product Code: 111321218
Original Version
Chassis Series: TC2-A
WE
9. VCR Main Mechanism Parts Location
9-1. Mechanism ass’y (Top view) .................................... 22
9-2. Mechanism ass’y (Bottom view) ............................... 23
9-3. Front loading mechanism .......................................... 23
10. Mechanism Dismantling and Reassembling
10-1. Cassette drive gear (Right) ................................... 24
10-2. Cassette drive gear (Left) ..................................... 25
10-3. COMPL motor bracket (Loading motor block) ..... 26
10-4. Tape loading mechanism ...................................... 29
10-5. Capstan motor ....................................................... 32
11. VCR Service Adjustments
11-1. Test points for tape path adjustment .................... 33
11-2. Location of adjustment point ................................. 33
11-3. Sewicejigs ............................................................ 34
11-4. Mode selector (VHJ-0050) handling instruction ... 35
11-5. Tape path adjustment ........................................... 37
11-6. Servo circuit adjustment ...................................... 39
11-7. Audio circuit adjustment ...................................... 39
11-8. Video still V-lock adjustment ................................ 40
12. Mechanism Maintenance and Checking
12-1. Periodic checking and maintenance items .......... 41
12-2. l_#mwo~e~roceedwhen the cassette cannot be
................................................................ 42
13. Cabinet Parts tist ........................................................... 43
14. Video Section Parts List ................................................ 44
15. TV Section Chassis Electrical Parts List ........................ 49
REFERENCE NO. SM 520130
(E7WY)

Safety Precautions
An isolation transformer should be connected in the power
line between the receiver and the AC line before any
service is performed on the receiver.
X- Radiation Precautions
The primary source of X-RADIATION in television
receiver is the picture tube. The picture tube is specially
constructed to limit X-RADIATION emission. For
continued X-RADIATION protection, the replacement
tube must be the same type as the original including
suffix letter. Excessive high voltage may produce
potentially hazardous X-RADIATION. To avoid such
hazards, the high voltage must be maintain within
specified limit. Refer to this service manual for specific
high voltage limits. If high voltage exceeds specified limits,
take necessary corrective action. Carefully follow the
instructions for +B1 volt power supply adjustment, and
high voltage check to maintain the high voltage within the
specified limits.
–2–

Specifications
TV section
Power source AC 110-240 Volts, 50/60 Hz.
Receiving system PAL(B/G, D/K, 1,M/M), SECAM(B/G, D/K,1,M/M), NTSC(B/G, D/K, 1,M/M)
Channel coverage VHF: E2– E12, J1 –J12, A2-A13, C1 –C12, R1 –R12
CATV: S1 –S20, X, Y, Z
UHF:E21 –E69, J13 –J62, A14 –A69, C13 –C57
Aerial input impedance 75 Q
Audio output (Music )2.0 w
Ext. terminals AV inputs:
Video input (Phono jack) X1(1.OVp- p, impedance 75 S2)
Audio input (Phono jack) X1(142mVrms, impedance more than 47k S2)
AV output:
Video output (Phono jack) X1(1.OVP- p, impedance 75 S2)
Audio output (Phono jack) x1(142mVrms, impedance less than 1kQ)
Set dimensions
Set weight
VCR section
Format
Video signal
Video heads
Tape speed
Headphone jack: Mini. jack X1
494(W) x500(H) x473(D)mm
approx. 23.0 Kg
VHS
PAL/MESECAM/NTSC
2heads
PAUMESECAM:
SP: 23.39 mm/see.
LP: 11.70 mm/see.
NTSC:
SP: 33.35 mm/see.
LP: 16.67 mm/sec.(PIayback only)
EP: 11.12 mm/see.
Timer indication 24-hour indication
Power failure backup Approx. one hour
Specifications subject to change without notice.
–3–

1. Mechanism Disassembles
1-1. Cabinet Back Removal
1)Remove 9screws.
2) Pull the cabinet back off and remove the cabinet back.
1
II 1IIII
IEL
--
1-2. Chassis Removal
1)Remove the cabinet back.
2) Remove 2screws fixing the video mechanism.
3) Disconnect “KOS’’(Speaker lead) and “K6B’’(Degaussing Coil lead) on the Power/Deflection Unit.
4) Remove the chassis (Main Unit and Power/Deflection Unit) completely by sliding straight back.
Screw
K(
K6B”
Power/Def in Unit
-/
Video Mechanism
/
/Screw
–4–

L1-3. Video Mechanism Removal
1) Remove the chassis (Main Unit and Power/Deflection Unit) completely.
2) Remove the VIDEO UNIT by removing 2screws.
3) Disconnect “K2A, “K213”, “K2D on the Main unit.
4) Take off lead wires and AC cord from clamps on the shield cover.
5) Separate the Main unit from the Power/ Deflection Unit.
.6) Disconnect “KY” lead from the Main Unit.
Power/Deflection
Unit
L
7) Remove the shield
11 \-’l
I:rewwi
I
I#l
II
AC Cord “Main Unit
Video Mechanism
cover by removing 3screws.
Video Unit
/
,KY
Shield Cover
(Video Mechanism)
Screw
–5–

8) Remove the shield cover by removing 2screws (screw-A).
9) Remove the screw-B.
IF
Sc
Shield
:rew-A
Cover
Main U
10) Remove 3screws on the back of the Main unit.
11) Remove the Video Mechanism from the Main unit.
BACK SIDE
—Screw-B
—---=4
Clamp
Screw
—
Pre-amp. Unit
Slide the Video Mechanism
to take off the clamps.
Video Mechanism
Main Unit
–6–

1-4. Service Procedure
1)Turn the Video mechanism 180 degrees, and set as illustrated bellow.
2) Reconnect “k2A, “K2B” and “K2D.
J
/
w
i:
N
Z~Ou_~ jla,
Power/Deflection Unit
Video Mechanism II P
\Turn 180 degrees
=Power/Deflection Unit
Main Unit
–7–

1-5. Replacement of the reel drive beltBELT
1) Remove the Video Mechanism from the Main Unit.
2) Replace the reel drive belt,
\JReel Drive Belt
..
1-6. Video mechanism disassembles
1)Disconnect the flat cables from “CN9301” and “CN81 1”.
2) Remove the Pre-amp. unit by removing the screw.
3) Separate the Video Mechanism from the Main unit.
/
Main Unit \\\\ f
\\&n3-a ~deounit
~
CN811
–8–

4) Remove the screw-A (2 screws), screw-B and the screw-C.
.
5) Remove the screw-D (2 screws).
(Unlock by pressing the clamp-A~ Slide the cassette base in the direction of the arrow
4Remove the screw-D)
6) Remove the Video Mechanism from the mechanism holder.
Screw-A
Screw-B
Screw-A
Screw-C
99
\
\4
\~deoMec~ismHo,der
Cassette Base
>
Screw-D
I
/
/
/
–9–

7) Remove the Cassette Door as follows.
Washer Spring
\
~-
d
Cassette Door
*\Cassette Door
8) Remove the cassette mechanism as follows.
@Remove two screws.
@Disconnect three connectors.
@Cut the wire band.
@Remove the cassette mechanism by sliding and unlocking the two hooks.
Video Mechanism
Wire Band
Connector
FTE Head
Screw
_—.
-Y&!!!%7
Hook
Cassette
Mechanism
~Cassette Door
Screw-
–lo–

1-7. Cassette mechanism assembly
1)Align the EJECT mode positioning alignment mark to the Apositioning alignment mark.
L
/“<e;;%
Dress the wires with the wire
band
0
/
/
I\\
.
\
f
I1[ \
Loading
II 1
I
/
F
i
m
8
8
8
\
\
\1
1
/
/
0
–11–

2. Service Mode
Memory IC (IC81 O) replacement
Since part of adjustment data for the circuit is stored in the memory IC (IC81O) that comes with the CPU
(IC800), the adjustment data of the service mode must be checked and re-input (1. PF+OO, 2.VF K+00)
when the memory IC is replaced.
To enter the service mode
(1) Switch on the TV set.
(2) Press and hold the 9STOP button of the remote control transmitter or the TV set for more than 10 seconds.
STOP
*To exit from the service mode, switch off the
Service mode display
or
TV’s power
●*CC
STOP ‘
by pressing Power ON/OFF button.
ITo select an adjustment item, press the Programme UP/DOWN (PA, PV‘
DATA
1.PF 01
/
Uuuu
MENU
RR--l
o‘A
OK A+
80
mmcTn D
Adjustment item Adjustment data
To change an adjustment data, press the VOLUME ( - +, a – )button.
Uuuu
MENU
Ho‘A
Table of the adjustment data
button.
-,
d
Screen display Adjustment item Data Range of data Remarks
1.PF Power trouble diagnosis 00 o–3 See page 12
2.VF VCR self diagnosis 00 o–99 See page 13
–12–

3. Power Circuit Protection and 3-2.Power circuit problem self diagnosis
Self Diagnosis Display 1)Enter to the service mode by pressing and holding the
-■STOP button for more than 10 seconds.
This unit display the results of the self diagnosis it carries
out in two digits on the screen when problems occur.
Although these digits will only roughly tell you what kind
of problems have occurred, use them when servicing the
unit.
3-1. Power circuit protection
■Detection of the TV section power failure
If the pin-22 of IC800(CPU) voltage is less than 1.5V
for more than 1.0 second.
1RL621 is opened
TV power is turned OFF {TV set goes to the standby
mode. However, VCR power is ON).
G
■Detection of the VCR section power failure
If the pin-23 of IC800(CPU) voltage is less than 1.5V
for more than 1.0 second.
*
VCR and TV powers are turned OFF.
2) Select” 1. PF” using the Programme UP/DOWN
(PA/P V) button.
Service mode display
DATA
1.PF 01
Self diagnosis results are as follows;
DATA
00
Problem
No problem
01 ITVsection power failure
02 IVCR section power failure
03 IBoth of TV and VCR section power failure
Be sure to set the data of power failure to “00 “after
■To exit from the power circuit protecting mode, servicing.
Press the Power ON/OFF button of the TV set or
the remote control transmitter.
When the power is not turned on by pressing the
Power ON/OFF button, repair the power circuit.
–13–

3-3. VCR self diagnosis
1) Enter to the service mode by pressing and holding the
■STOP button for more than 10 seconds.
2) Select” 2. VF” using the Programme UP/DOWN
(PA/P T) button.
Be sure to set the data “00 “after servicing
using the VOLUME( A+, ~– )button.
VCR self diagnosis results
Service mode display
DATA
2.VF 02
No. Problem Main Possible Cause Mechanism Operations and State
After Occurrence
00 No problem
The cylinder does not rotate. ●The cylinder motor is faulty. Shifts to the STOP mode.
01 ●The control of the cylinder motor is
faulty.
●The tape winds around the cylinder.
The take-up reel does not rotate. ●The take-up reel is caught. Shifts to the STOP mode.
02 ●The belt is faulty.
●The take-up torque has decreased.
The capstan motor does not ●The capstan motor is faulty.
03 Shifts to the STOP mode.
rotate. ●The control of the capstan motor is
faulty.
The tape cannot be loaded with the ●Error in the operations of the tape Unloads, shifts to the INITIAL mode, and
cassette inserted. loading mechanism.
04 (But unloading can be performed.) the power goes off.
●Foreign particles in the tape load- ing
mechanism.
●The tape end sensor is faulty.
●The reel brake of the tape cassette
has not been released.
The loading and unloading ●The tape guide is caught. The power is forcibly turned off with the
05 cannot be performed with the ●The loading motor is faulty.
cassette inserted. mechanism at its current position.
●The control of the loading motor is
faulty.
Front unloading cannot be ●The cassette holder mechanism is Front loads and shifts to the STOP or
06 performed when ejecting the faulty. INITIAL mode.
cassette. (Front loading can be ●The front door is caught. When the power switch is turned on
performed.) before eject operations: Shifts to the
STOP mode.
When the power switch is turned off
before eject operations: Shifts to the
INITIAL mode and the power goes off.
Front loading and front unloading ●The tape cassette is caught in the The power is forcibly turned off with the
07 cannot be performed when cassette holder mechanism.
●The gears of the front loading drive mechanism at its current position.
ejecting the cassette. mechanism have not engaged
properly.
The mechanism becomes 1(BRAKE) ●The mechanism mode switch contact The power is forcibly turned off with the
08 while moving from 2(STOP, FF/REW), is faulty. mechanism at its current position.
3(STILL), 4(PIAY) and to 5(IDLER).
The mechanism becomes 7(INITIAL) ●The mechanism mode switch contact Carries out tape takt+up operations,
while moving from 1(BRAKE), 2is faulty. shifts to the INITIAL mode, and the
09 (STOP, FF/REW), 3(STILL), 4(PLAY) power goes off.
and to 5(IDLER).
–14–

4. ICS Pin Descriptions
4-1. CPU pin descriptions (IC 800)
Pin No. Function IDescription
1Vcc WPin No. IFunction IDescription
44 lTV/ExternalNCR switch-2 I“L’’=TV&PIAY,’’H’’=Ext.
45 lTV/ExternalNCR switch-l l“L’’=Ext.& PlAY,’’=TV=TV I
I21GND III1
46 Recording LED output “H’’=Recording I
1,
I3IPower failure detection IPower failure=’1” I47 ISIF system switch output-1 ]“H’’=4.5MHz I
I4!AFT voltage input 10-5V I
r-I
5PAL=L(out),SECAM=M( input),
PAIJSECAM/NTSC output NTSC.H(~ut) Timer recording LED
48 ‘)H’’=Timer recording
output I
49 SIF system switch output-2 q-fn=5.5MHz
50 SIF system switch output-3 “H’’=6.OMHZ
I6!EEPROM serial clock I
1,
I7IEEPROM serial data
8BAND switch output-1 “l-’’=VHF-L, “H’’=VHF-H,UHF
9BAND switch out~ut-2 “L’’=VHF-L &H, “H’’=UHF
51 Power ON/OFF output “L’’=OFF,’’H’’=Standby,ON
52 SIF system switch output-4 “H’’=6.5MHz
53 ISnow mute output I“H’’=Mute ON I
10 Tuning voltage output
11 Chroma-lD signal input Monochrom=”H”
12 Svstem control communication clock im.wt and output Colour system switch
54 output-3
55 SIF system switch output-4 “L’’=3.58MHz
56 Power ON/OFF output “L’’=OFF,Standby,’’H’’=ON
57 Repeat LED output “H’’=Repeat ON
!13 ISYsterncontrolcommunicationdata Output
14 System control communication data input
15 On screen display chip select
16 On screen display serial clock 58 NTSC –H“H’’=NTSC
59 Audio mute output “H’’=Mute ON
17 On screen display serial input
18 Power switch ON/OFF “L’’=OFF, “H”=Standby, ON
19 Ident signal input-1 /“L’’=3.58MHz
32Hz output
60 Colour system switch
output-2 “L’’=4.43MHZ I
61 Colour system switch
output-1 “H’’=SECAM
62 DAC (Digital analogue convert) DI output
20 Ident signal input-2 “L’’=Tu sync.
21 Sync. –ID signal input-2 “L’’=AV sync.
63 DAC (Digital analogue convert) clock output
64 DAC (Digital analogue convert) LD output
22 Power failure detect output ~’L’’=Problem
(TV section)
23 Power failure detect output ,,p=problem
(VCR section) 4-2. IC1930 (DAC) pin descriptions
,
24 Remote control input “L”=Active
25 Vertical sync. (50/60Hz judgment) Pin No. Function Description
1Load input “L”= Active
2Clock input
IFront loading start switch
26 input “H’’=Cassette in II3IData input
4ITINT output I“H’’=Except NTSC I
I27 IReset input I“l_’’=Reset I
J
28 32.768 KHz oscillator input For clock
29 32.768 KHz oscillator output For clock [5Sharpness output I
6i50160 Hz outout I “L”=50H12 I
30 4MH2 oscillator input For CPU clock
31 4MHz oscillator output For CPU clock I7]AFT ON/OFF output I“L”= AFT ON I
8GND
9Vref L
10 Vref H
11 Vcc (Analogue)
12 Contrast output
13 Brightness output
14 Colour output
15 Volume output
16 Data outDut Not used
32 GND
33 Key return O“H’’=Active
34 Key return 1“H”=Active
35 Key return 2“H’’=Active
36 Option switch return “H’’=Active
37 Key strobe O“H’’=Active
38 Key strobe 1“H”=Active
I39 Key strobe 2“H’’=Active I
I40 IKey strobe 3I“H”=Active I17 Vcc (Digital)
18 Mute input Not used
41 Key strobe 4“H’’=Active
42 50/60 Hz output “L”=50Hz, “H’’=6oHz
43 TV/External/VCR switch-3 “L”=TV &PLAY, “H’’=Ext.
–15–

5. TV Section Service Adjustments
—
t%I I
R((
KoS
POWER /DEF. UNIT 1nKO1O
Edtii!!?i!’”
r‘-l
.L600 SW601
K6D
‘~H
●
●
Q601
T651
CONVERTER
TRANS.
&
o
C606
—
f
n9
T401
/—
R
●
0TP621
115V
1I\)
=1” 0u
0
7I
UJ
c
0
0VR51 O
V-SIZE
L
o
00
;
SW501
V-CENTER
0!
UP
I
~OvJND D~
fFocus Adjustment
(1) Receive the monochrome circular pattern.
(2) Set the brightness to normal and contrast to
maximum.
(3) Adjust the focus control on the F.B.T for the
best focus on the screen center. –16–
+115V Adjustment
‘(1) Tune the receiver to an active channel.
/(2) Set the Brightness and Contrast to
normal.
(3) Connect Digital voltmeter to TP621 and
the ground.
(4) Adjust VR621 for115V *0,5V,
+15V Adjustment
(1) Tune the receiver to an active channel.
(2) Set the Brightness, Contrast and Colour
to normal.
(3) Connect Digital voltmeter to TP631 and
the ground.
(4) Insert avideo cassette to the VCR, and
set the recording mode by pressing the
REC button.
(5) Turn off the TV set by pressing Power
ON/OFF button.
(6) Adjust VR622 for 15V f0.2V.
Vertical Size Adjustment
/(1)Receive the monochrome circular pattern.
(2) Set the Brightness and Contrast to
maximum,
(3)Adjust vertical size (VR51 O) control for full
scan.
rtical size
Vertical Center Adjustment
(1)Receive the monochrome circular pattern.
(2) Set the Brightness and Contrast to maximum.
(3) Adjust vertical centering using SW501.
rtical center

L
L
.
I%
POWER /DEF. UNIT ouVR51 O
V-SIZE r
q
~ilg
oSW501
V-CENTE
T400
D!l
“p -IL K6E
F.B.T K4B
SCREEN f1
FOCUS Eq,,, ....0 n~
TP452 m
\
Grey Scale Adjustment
(1) Receiver the monochrome circular pattern.
(2) Set the brightness to normal, contrast to maximum.
(3) Set the service switch (SW220) on the main unit at the service side.
(4) Connect aoscilloscope to TP -7C(+) and TP-7F(- )on the CRT unit.
(Probe attenuation *10:1, Sync.V- sensitivity +O.05V
Signal coupling *DC)
Using VR740 on the CRT
unit, adjust “a” to be OV. -“=:v
(5) Set the drive volume (VR702 andVR712) at their mechanical center.
(6) Set the bias volume (VR701, VR721 andVR711 )to minimum. (fully counter
clockwise).
(7) Turn the screen volume on the FBT to obtain just visible one coloured line.
(8) Adjust each bias volume (VR701 -blue, VR721 -green and VR711 -red)
alternately until adim white line produced.
(9) Set the service switch (SW220) at the normal side.
(1O) Adjust the drive volume (VR702 -blue and VR712 -red) alternately to
produce normal black and white picture.
(11)Check for proper grey scale tracking at all brightness levels.
NOTE: If the grey scale adjustment is made after picturetube replacement,
check the high voltage.
,
VR740
\CRT UNIT
MAIN UNIT Service Switch
E:,AS p,*.-
VR721 U’m B
GREEN BIAS
VR701
BLUEBIAS
Q
km K7P
VR712
RED DRIVE bTP-7F
o
VR702
‘t
I
.BLUEDRIVE o ‘-~c‘K7M &o
(+) (-)
Oscilloscope
I1-AGC Adjustment
Al 01
1I
NOTE; Do not attempt this adjustment with weak signal.
(1) Tune the receiver to most clearest (or strongest) VHF
station in your area. Set the brightness and contrast
controls to maximum. Set the colour control to
minimum.
(2) Set AGC (VRl 20) control to mid- range.
(3) Turn AGC control in direction which causes snow to
appear, then in the opposite direction until the snow
just disappears.
\Horizontal Center Adjustment
(1) Receive the monochrome circular pattern.
(2) Set the Brightness and Contrast to normal.
(3) Adjust VR351 for optimum horizontal center position.
ontal center
–17–

Horizontal Width Adjustment \
(1)Receive the monochrome circular pattern.
(2) Set the Brightness and Contrast to
maximum.
(3) If the picture is too wide+ Cut J401.
If the picture is too narrow* Short J401.
Important Note:
If J401 is cut, its gap must be more than
5mm to prevent sparks.
‘40’=0rethan5mm
High Voltage Check
(1)Connect ahigh voltage probe to anode lead
of the picture tube.
(2) Receive the monochrome circular pattern.
(3) Set the Brightness and Contrast to
maximum.
(4) High voltage must be 25KV *1KV.
MAIN UNIT
/
/
a
n
K2X
u
IC81 O
I
MEMORY -.
..
SW
●
F=l”
II
POWER /DEF. UNIT
Clock Frequency Confirmation
/
(1) Receive the most clearest station in your area.
(2) Connect Quartz Counter to IC800 pin-1 9 and the ground.
(3) Connect diode(l S1555) between IC800 pin-36 and IC800 pin-37.
IIC800(CPU)
DIODE (1S1 555)
(4) Disconnect the AC power plug from the mains to reset the CPU(IC800).
(5) Reconnect the AC power plug to the mains, and switch on the TV set.
CPU is in the Clock Adjustment mode.
(6) Confirm the OSC frequency is 32 Hz.
(7) Disconnect diode from the CPU, and disconnect the AC power plug from the
mains to reset the CPU.
Clock Adjustment mode is reset.
.
–18–

6. VIF Adjustment
Detector Adjustment Overall Waveform
Adjustment (PAL)
K2B pin-4
(or IC671 pin-1)
IC101 pin-48
No Band(with Jig-B)
Tuner-TP
TP-F
QI 97-Base
Sound Trap Adjustment
(NTSC) Overall Waveform
Confirmation (NTSC)
Item
—
c
o
.-
%
al
c
c
6
—
c
0
.-
.%
-0
c
8
—
K2B pin-4
(or IC671 pin-1)
IC101 pin-48
No Band(with Jig-B)
Tuner-TP
TP-F
Q197-Base
DC 15.OV
IF AGC(3.5-4.5V)
Setting Band
Output Probe
Input Probe
DC 12V(with Jig-A)
Sweep ATT
Output Probe
Dumping Resistor
Oscilloscope Sens.
System
K2B pin-4
(or IC671 pin-1)
ICI 01 pin-48
No Band(with Jig-B)
Tuner-TP
TP-F
Q197-Base
K2B pin-4
(or IC671 pin-1)
IC101 pin-48
No Band(with Jig-B)
Tuner-TP
TP-F
Q1 97-Base
40 dB
side b
not used
10OmV/div
PAL (with Jig-A side b)
40 dB
side b
K2E pinl –pin3
10OmV/div
PAL (with Jig-A side b)
20 dB
side b
K2E pinl –pin3
10OmV/div
PAL (with Jig-A side a)
40 dB
side b
K2E pinl –pin3
10OmV/div
NTSC (with Jig-A side b
Adjust PiS 50% *10VO
Adjust P(38.9MHz) to and Cis 5070 t10’%.by
be maximum by using using Tuner Converter Adjust S(4,5MHZ) to be
T131 .coil and T1 01. minimum by using T1 03.
Confirm Pis 4570 f
10VOand Cis 65V0 k
10?40.
Adjustment a
cP
s
Waveform
Output Probe JIG- A(System) Input Probe
‘“’a’rkerTT=h’Jm
m
10KQ Oscilloscope
“G”
I!\. -’-. I
MAIN UNIT
~
m
n
2
mConverter Coil
2
u
6= s
[C671 IC673
aCN703
!2 m-
Sound Trap Adj. (NTSC) Overall Waveform Adj.(PAL)
“–.
[Y
.,.,.,.
:;::.:.:.:.
,:;.,.,.,.,.,.:.
l131pJ y
—- ~:;::~:; :::;::
~:
> “- ‘Iyo:wg’ ,=,
“ -:- .
Wplrl IC672 Resist=
–19–

7.AFT Adjustment
Item
DC 15.oV
IF AGC(3.5- 4.5V)
Setting Band
Output Probe
Input Probe
DC 12V(with Jig-A)
Resonance Frequency
Adjustment (Rouah) Resonance Frequency Adjustment (Fine)
AGC Voltsge Alignment
—
c
o
.-
Z
al
c
c
8
c
0
.—
.%
-u
c
s
K2B pin-4
(or IC671 pin-1)
IC101 pin-48
No Band(with Jig-B)
Tuner-TP
TP-F
Tuner-TU
K2B pin-4
(or IC671 pin-1)
IC101 pin-48
No Band(with Jig-B)
Tuner-TP
IC101 pin-44
Tuner-TU
K2B pin-4
(or IC671 pin-1)
IC101 pin-48
No Band(with Jig-B)
Tuner-TP
ICI 01 pin-44
Tuner-TU
Sweep ATT
Output Probe
Dumping Resistor
Oscilloscope Sens.
System
SG Output
25 dB
side b
R124
100mV/div
PAL (with Jig-A side b)
None
25 dB
side b
Not used
1Vldiv
PAL (with Jig-A side b)
35dB
25 dB
side b
Not used
1Vldiv
PAL (with Jig-A side b)
35 dB
Keep AGC voltage.
Set the VIF Adjustor Sweep
off and pix. SG to CW output.
Using T1 31, adjust DC
voltage to be 3.6V *0.2V.
Fix the AGC voltage when the
overall waveform level is adjusted
at l. OVp-p.
Keep AGC voltage, and Confirm
the maker position Pis near by
the reference line,
Adjustment
38.9MHz marker
f ./ referenceline
Waveform
Output Probe JIG- A(System)
33K Q a
~:.;.:.:.;.;.:.:.;.::\
100 S2~Darnp!ng ,fieslstor
:::::.. ::.::;’
... .
\QYa
.Oscilloscope
Tuner TP w
u
CN702
\oD vRI 24(Solder
-Base side) JIG-B
(No Band)
MAIN UNIT 2.2K O
P
i
OFF 5V
2.2KQ12V
ON 5V
I
pin
d
181 4
@+
T103
E
❑
T101
●uou
A== K2C
4-pin IC672 -Tuner TP
FL
–20–