Safety Instructions 2
Technical Specifications 3
Instructions Manual 4
Block Diagram 9
Pin Voltages of IC’s 11
Oscillograms 13
Electrical and Service Adjustments 17
Channel Frequency Tables 20
Parts List 22
Circuit Diagrams Attached
SAFETY INSTRUCTIONS
GENERAL GUIDELI NES
1. It is advised to insert an isolation transformer
in the AC supply before servicing a hot
chassis.
2. Potentials as high as 33KV are present when
this receiver is in operation. Operation of the
receiver without the rear cover involves the
danger of a shock hazard from t he receiver
power supply. Servicing should not be
attempted by any one who is not
competent with the precautions necessary
when working on the high voltage
equipment. Always discharge the anode of
the tube.
3. When servicing observe the original lead
dress in the high voltage circuits. If a short
circuit is found, replace all the parts which
have been overheated or damaged by the
short circuit.
4. Always use the manufacturer’s replacement
safety components. The critical safety
components marked with
on the
schematics diagrams should not be
replaced by other substitutes. Other
substitute may create the electrical shock,
fire or other hazards. Take attention to
replace the spacers with the originals.
Furthermore where a short circuit has
occurred, replace those components that
indicate evidence of overheating.
5. After servicing, see that all the protective
devices such as insulation barriers, insulation
papers, shields and isolation R-C
combinations are correctly installed.
6. When the receiver is not being used for a
long time of period of time, unplug the
power cord from the AC outlet.
7. After servicing make the following leakage
current checks to prevent the customer
from being exposed to shock hazard.
LEAKAGE CURRENT COLD CHECK
1. Unplug the AC cord and connect a jumper
between the two prongs of the plug.
2. Turn the receiver’s power switch on.
3. Measure the resistance value with an
ohmmeter, between the jumpered AC plug
and each exposed metallic cabinet part on
the receiver, such as screw heads, aerials,
connectors, control shafts etc. When the
exposed metallic part a return path to the
chassis the reading should be between
4Mohm and the 20Mohm. When the
exposed metal does not have a return path
to the chassis, the reading must be infinite.
LEAKAGE CURRENT HOT CHECK
1. Plug the AC cord directly in to the AC
outlet. Do not use an isolation transformer
for this check.
2. Connect a 2Kohm 10W resistor in series with
an exposed metallic part on the receiver
and an earth, such as a water pipe.
3. Use an AC voltmeter with high impedance
to measure the potential across the resistor.
4. Check each exposed metallic part and
check the voltage at the each point.
5. Reverse th e AC plug at the outlet and
repeat each of the above measurements.
6. The potential at the any point should not
exceed 1.4 Vrms. In case a measurement is
outside the limits specified, there is the
possibility of a shock hazard, and the
receiver should be repaired and rechecked
before it is returned to the customer.
HOT CHECK CIRCUIT
TO INSTRUMENTS
EXPOSED
METALLIC PARTS
AC-Voltmeter
Water pipe
(earth)
2 K Ohm
Figure 1
X-RAY RADIATION WARNING
The primary source of X-ray radiation in this receiver
is the picture tube. The chassis is specially
constructed to limit X-ray radiation. For continued
X-ray radiation protection, replace the tube with
the same type of the original one.
CAUTION
AFTER REMOVAL OF THE ANODE CAP, DISCHARGE
THE ANODE OF THE PICTURE TUBE AND THE ANODE
CAP TO THE METAL CHASSIS, CRT SHIELD, OR THE
CARBON PAINTED ON THE CRT WITH A HIGH
VOLTAGE PROBE AND MULTIMETER (SELECT VDC)
AND THEN SHORT CIRCUIT DIRECTLY TO DISCHARGE
COMPLETELY.
TECHNICAL SPECIFICATIONS
Power source:
Power consumption (max.)
85 W 20”, 21”
Standby power consumption
Aerial impedance
Receiving system
PAL SECAM BG
PAL SECAM BG DK
PAL I
Receiving channels
VHF BAND III CH5-12
CABLE TV S1-41
UHF BAND CH21-69
Connect a digital voltmeter to the cathode of diode D607 at the AV mode of the TV and set the screen
voltage to the minimum with the screen potentiometer. Adjust the main supply voltage (B+) with P607
potentiometer to the following value (after supply adjustment, readjust Screen and focus voltage).
To enter the Service Mode, ‘Service In/Out” button on the Service Remote Control or activate the
“Picture Menu” with the user remote control and press “9301” (Press “0” button to exit the Service
Mode).
“Red” , “Green”, “Yellow” and “Blue” Teletext buttons are for Feature Setup, Geometry, White Balance
and IF menus respectively.
2.1 IF Adjustments
2.1.1 PAL SECAM BG/DK/I
• Disconnect IF1 and IF2 terminals on the main chassis.
• Apply a 38.9 MHz PAL colour bar RF signal to the pin 1 of F101 with a pattern generator.
• Switch on the Service Menu with the Service RC and press “Blue” teletext button.
• Check that value of “PVC38” is “07”. Adjust the coil LC101 until the the “OK” is seen.
• Press “OK” button on the Service RC.
• Exit from the service menu with the Service RC.
• Reconnect IF1 and IF2 terminals on the main chassis.
Note: “PVF38” is for fine tuning. However, it is automatically applied when “OK” button is pressed at
“PVC38” item. Thus any manual adjustment is not required.
2.1.2 SECAM L/L’
• They would not to be adjusted . “PVC33” and “PVF33” were reserved for Secam LL’.
2.2 AGC Adjustment
• Apply a signal with amplitude 65±1 dBuV to the antenna input of TV with a pattern generator
(switch sound carrier to Off and switch “Video Ext” to On).
• Switch on the Service Menu with the Service RC and press “Red” teletext button.
• Find the “AGC” with P+ / P- buttons.
• Measure the amplitude of 38.9 MHz sinusoidal signal on pin 11 (IF2) of Tuner with an oscilloscope.
• Change “AGC” to get 640 ± 20 mVpp.
• Add 5 to “AGC” value and change “2.AGC” to this value.
• Exit from the service menu with the Service RC.
2.3 Screen Adjustment
• Switch on the Service Menu with the Service RC and press “Yellow” teletext button.
• Find item “SCRN” in the menu. Apply color bar pattern
• For 14” sets:
Adjust the Screen potentiometre until the voltage across the pin of R727 (that is
connected CRT cathode) and ground is 139±3 VDC.
• For 20”-21” sets: Adjust the Screen potentiometre until the voltage across the pin of R727 (that is
connected CRT cathode) and ground is 164±3 VDC (For 20”Ekranas CPT, adjustment value
is154±3 VDC )
• Exit from the service menu with the Service RC.
2.4 White Balance Adjustment
• Apply a white pattern with a pattern generator to the antenna input.
• Enter the Service Menu with the Service RC and and press “Yellow” teletext button.
• Select “B.DRV” option with P+ / P- buttons and change its value to “32” with V+ / V- button.
• Adjust “R.DRV” and “G.DRV” for white balance.
• Adjust “R.CUT” and “G. CUT” for red and green cut off (There is no blue cut off adjustment).
• If white balance can not be adjusted properly change “B.DRV” value.
• Exit from Service menu.
2.5 Geometry Adjustments
• Apply the cross hatch pattern with a pattern generator to the antenna input.
• Enter Service Menu with Service RC and press “Green” teletext button.
• Adjust Vertical Amplitude with “V.4:3” option.
• Add 18 to ““V.4:3” value and change “V.16:9” to this value.
• Adjust vertical position with “V.POS”, vertical linearity with “LNRTY”, horizontal position with
“H.POS”.
• Substract 14 from “V.4:3” value and change “V1. 60” to this value.
• Add 4 to “V.4:3” value and change “V2. 60” to this value.
• Set “VP.60” to the same value of “V.POS”.
• Set “LN.60” to the same value of“LNRTY” .
• OSD window position can be centered on the screen with “OSD.H” and “OSD.V”.
• Exit from the Service Menu.
Note that: There is no horizontal width adjustment in this chassis. It can be adjusted by changing power
supply voltage in the interval of -1 and +1 V.
2.6 Feature Setup
Enter the Service Menu with the Service RC and and press “Red” and “Blue” teletext button. Check that
below features match with the set.
TUNER : Phillips, Sharp&Alps, Panasonic, Temic
ST.BY : YES (Default, Automatic switch off is active), NO (can be used during repair)
AV2 : YES (Front AV is available), NO
CLR.S : PAL, PAL/NTSC3.5 (+NTSC Playback), PAL/SECAM, PAL/SECAM/NTSC3.5 (NTSC Pback)
SND.S : BG, I, BG+DK, BG+LL’
QSS/I : INTERCARRIER, QSS
TEXT : NON TEXT, DEFAULT (Teletext), FASTTEXT
LANG : A (West Europe), B (East Europe)
HOTEL : NORMAL TV, HOTEL TV
RGBIN : YES (When Scart RGB exists, aerial isn’t showed–for only for some Hotel TVs), NO (Default)
APR : ON (Auto RGB level control is available) , OFF
B.STR : ON (Black level control is available), OFF
ATS : YES (Automatic tuning system is on), NO
AVL : YES (Automatic Volume Limiter is on), NO
ZPG : YES (Timer Programmed channel switching function is on), NO
ZAPP : YES (One button channel switching function is on), NO
2.7 Hotel Mode
If “Hotel” option in the Service Menu is selected as “HOTEL TV”, the setup menu is get by entering “4658”
in the “Features Menu”. The setup menu includes the following items:
1. HOTEL MODE : On/off selection and end of TV channels (start is “00”)
2. RADIO MODE : On/off selection and start of Radio channels (end is “99”).
3. MAX VOLUME : Maximum allowed volume level
4. RESET ADJ. : Sound and picture preset values that will be applied after reset operation
5. MESSAGE : Welcome Message can be edited (max. 148 character long)
6. INFO SCREEN : Information Message can be edited (3 pages, each 500 character long)
Customer gets these pages by pressing “INFO” button of Remote Control
7. LOAD DATA : Not operational
8. SAVE DATA : Not operational
2.8 Factory Settings for Service Mode
Values given in Table 1 are typical values and can vary according to the CRT type.
14" 20" 21"
AGC Automatic Gain Control 1 323232
2.AGC Automatic Gain Control 2 AGC + 5AGC + 5AGC + 5
ST.BY Standby YESYESYES
PVC38 VOC Coarse (BG/I/DK) 070707
PVF38 VCO Fine (BG/I/DK) 686262
PVC33 VOC Coarse (LL') 071313
PVF33 VCO Fine (LL') 646464
APR Auto RGB level control ONONON
B.STR Black level control OFFOFFOFF
QSS/I QSS/Intercarrier INTERCARRIERINTERCARRIER INTERCARRIER
G.DRV Green level 323232
R.DRV Red level 404032
B.DRV Blue level 373732
R.CUT Black level offset red 363632
G.CUT Black level offset green 323232
SCRN Screen (used for screen adj.) 000
HPOS Horizontal shift 303232
VPOS Vertical shift 121107
V.4:3 Vertical amplitude 4/3 PAL/SEC 233236
V.16:9 Vertical amplitude 16/9 PAL/SECV.4:3 + 18V.4:3 + 18V.4:3 + 18
LNRTY Vertical linearity 511349
VP.60 Vertical amplitude NTSC 121107
V1.60 Vertical amplitude 4/3 NTSC V.4:3 - 14V.4:3 – 14V.4:3 – 14
V2.60 Vertical amplitude 16/9 NTSC V.4:3 + 4V.4:3 + 4V.4:3 + 4
LN.60 Linearity NTSC 511349
OSD.H OSD Horizontal Shift 313129
OSD.V OSD Vertical Shift 393938
Table 1
2.8 Exit from Service Menu
During exit from service menu, the software version and feature options (hexadecimal number) are
shown on the screen.
For example: SC1.120-01 66F3 T03030702