Sanyo avm3651g schematic

AS
FILE NO.
SERVICE MANUAL Remote Control Color
Television
AVM-3651G (U.S.A.)
ORIGINAL VERSION
Chassis No. G7R-3651G0
NOTE: Match the Chassis No. on
If the Original Version Service Manual Chassis No. does not match the unit’s, additional Service
Literature is required. You must refer to “Notices” to the Original Service Manual prior to servicing the unit.
Contents
Safety Instructions . . . . . . . . . . . . . . . . . . 2
Service Adjustments. . . . . . . . . . . . . . 3 - 9
Service Hints. . . . . . . . . . . . . . . . . . . . . . 10
Mechanical Disassemblies. . . . . . . . . . . 11
Chassis Electrical Parts List . . . . . . 12 - 22
Cabinet Parts List . . . . . . . . . . . . . . . . . . 23
Component and Test Point
Locations . . . . . . . . . . . . . . . . . . . 24 - 27
Schematic Insert . . . . . . . . . . . . . . . 29 - 36
Schematic Notes . . . . . . . . . . . . . . . . . 29
Pin Layouts . . . . . . . . . . . . . . . . . . . . . 25
Capacitor and Resistor Codes . . . . . . 29
Block Diagram. . . . . . . . . . . . . . . 30 - 31
Voltage Charts . . . . . . . . . . . . . . . 30 - 32
Waveforms. . . . . . . . . . . . . . . . . . . . . . 32
Schematic Diagrams . . . . . . . . . . 33 - 36
Specifications
Power Rating . . . . . . . . . . . . . . . . . . . . . 120V, 60Hz
107W (Avg), 2.5A (Max)
Antenna Input Impedance . . . . . . . . . . . . . . . . 75W
UHF/VHF/CATV
Receiving Channel . . . . . . . . . . . . . . . . 2 - 13 (VHF),
14 - 69 (UHF),
01, 14-94, 95-125 (CATV)
Remote Ready . . . . . . . . . . 33 Key Remote Control
Sound Output . . . . . . . . . . . . . . . . . . . . . . 3.0 W/CH
Intermediate Frequency
Picture IF Carrier. . . . . . . . . . . . . . . . . . 45.75MHz
Sound IF Carrier . . . . . . . . . . . . . . . . . . 41.25MHz
Color Sub Carrier . . . . . . . . . . . . . . . . . 42.17MHz
Picture Tube . . . . . . . . . . . . . . . . . . . A90AEJ15X02
Semiconductors
Integrated Circuits. . . . . . . . . . . . . . . . . . . . . . . 12
Transistors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Except within Tuner and RC Pre-Amp.
Cabinet Dimensions
Width. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 848mm
Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . 751mm
Depth. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 618mm
REFERENCE No. SM780073
AVM-3651G, G7RBM, PRODUCT CODE 111355681
AS
— 2 —
SAFETY PRECAUTIONS
WARNING: The chassis of this receiver has a floating ground with the potential of one half the AC line voltage in respect to earth ground. Service should not be attempted by anyone not familiar with the precautions necessary when working on this type of equipment.
The following precautions must be observed:
1. An isolation transformer must be connected in the power line between the receiver and the AC line before any ser­vice is performed on the receiver.
2. Comply with all caution and safety-related notes provided on the side of the cabinet, inside the cabinet, on the chas­sis, and the picture tube.
3. When replacing a chassis in the cabinet, always be certain that all the protective devices are installed properly, such as control knobs, adjustment covers, shields and barriers.
DO NOT OPERATE THIS TELEVISION RECEIVER WITHOUT THE PROTECTIVE SHIELD IN POSITION AND PROPERLY SECURED.
4. Before replacing the back cover of the set, thoroughly inspect the inside of the cabinet to see that no stray parts or tools have been left inside. Before returning any television to the customer, the service technician must perform the following safety checks to be sure that the unit is completely safe to operate without danger of electrical shock.
ANTENNA COLD CHECK
Remove AC plug from the 120 VAC outlet and place a jumper across the two blades. Connect one lead of an ohm­meter to the jumpered AC plug, and touch the other lead to each exposed antenna terminal (UHF and VHF antenna ter­minals). The resistance must measure between 1M ohm and
5.2M ohm. Any resistance value below or above this range
indicates an abnormality which requires corrective action.
LEAKAGE CURRENT CHECK
Plug the AC line cord directly into a 120 VAC outlet. (Do not use an isolation transformer for this check.) Use an AC volt­meter, that has 5000 ohms per volt or more sensitivity. Connect a 1500 ohm 10 watt resistor, paralleled by a 0.15 µF 150 VAC capacitor, between a known good earth ground (water pipe, conduit, etc.) and all exposed metal parts of the cabinet (antennas, handle bracket, metal cabinet, screw heads, metal overlays, control shafts, etc.). Measure the AC voltage across the 1500 ohm resistor. The AC voltage should not exceed 750 mV. A reading exceeding 750 mV indicates that a dangerous potential exists. The fault must be located and corrected. Repeat the above test with the receiver power plug reversed.
NEVER RETURN A RECEIVER TO THE CUSTOMER WITHOUT TAKING THE NECESSARY CORRECTIVE ACTION.
X-RADIATION PRECAUTION
The primary source of X-RADIATION in solid-state receivers is the picture tube. The picture tube is specially constructed to limit X-Ray emission. For continued X-RADIATION protection, the replacement tube must be the same type as the original (including the suffix letter in the part numbers). Excessive high voltage may produce potentially hazardous X-RADIATION. To avoid such hazards, the high voltage must be maintained within specific limits. Refer to the X-RADIATION WARNING NOTE on the CHASSIS SCHEMATIC in this service manual for specific high voltage limits. If the high voltage exceeds specified limits, check the components specified on the chassis schematic diagram and take the necessary corrective action. Carefully follow the instructions for the +B Voltage Check and the High Voltage Check to maintain the high voltage within the specified limits.
HIGH VOL T AGE HOLD-DOWN TEST
To prevent X-RADIATION from the picture tube due to excessive high voltage, a HOLD-DOWN circuit is provided in the high voltage circuit. Every time the receiver is serviced, the high voltage HOLD-DOWN circuit must be tested for proper operation. Refer to the HIGH VOLTAGE HOLD­DOWN TEST in service adjustments.
PRODUCT SAFETY NOTICE
When replacing components in a receiver, always keep in mind the necessary product safety precautions. Pay special attention to the replacement of components marked with a star () in the parts list and in the schematic diagrams. To ensure safe product operation, it is necessary to replace those components with the exact same PARTS.
SAFETY INSTRUCTIONS
READING SHOULD NOT EXCEED 750 mV.
AC VOLTMETER
(5000 ohms per volt or more sensitivity)
TELEVISION
RECEIVER
Good earth ground such as a water pipe, conduit, etc.
AC OUTLET
1500 ohm
10 watt
0.15 µF 150V AC
To be touched to all of exposed metal parts. Voltmeter Hook-up for Leakage Current Check.
GENERAL
This set has an On-screen Service Menu system included in the CPU that allows remote operation for most of the service adjustments.
ON-SCREEN SERVICE MENU SYSTEM
1. Enter the Service Menu:
While pressing the MENU key, reconnect the AC power cord. The Service Menu Display will now appear. (See Figure 1.)
2. Service Adjustments:
Press the or key to select the desired service menu you want to adjust. (See page 4 for On-screen Service Menu.)
Use the + or – key to adjust the data.
3. Exit from the Service Menu:
Press the MENU key to turn off the Service Menu display.
SERVICE AD JUSTMENTS
— 3 —
IC802 (EEPROM) REPLACEMENT
When IC802 (EEPROM) is replaced, IC801 (CPU) will automatically write the initial reference data into IC802 for basic TV operation. However, the bus data should be checked and some bus data should be set up before attempting the service adjustments. (See pages 4 – 6 for detailed information.)
INITIAL BUS DATA SETUP
Note: When IC802 (EEPROM) is replaced, the Service Menu NO. 03 HP (H Phase), NO. 10 VSC (V S Correction), NO. 14
VC (V Comp), NO. 23 POS (Pre/Over/SW), NO. 28 PRE (Preshoot Adj), NO. 29 WP (White Peak Limiter), NO. 32 BSG (Black Str Gain), NO. 34 DCR (DC Reset), NO. 37 AF (Auto Flesh), NO. 41 RYA (R-Y/B-Y Angle), NO. 48 EWA (EW Amp), NO. 49 EWT (EW Tilt), NO. 50 EWP (EW Corner Top), NO. 51 EWB (EW Corner Bottom), NO. 55 STI ( Sub Tint), NO. 57 OPT (SA Option ), No. 58 OP2 (SA Option 2), and NO. 63 SBO (Sub Bright Offset) should be set up for proper TV operation before attempting the service adjustments.
1. Disconnect the AC power cord (AC 120V line).
2. While pressing the MENU key, reconnect the AC power cord. The Service Menu display will now appear.
3. Select NO. 03 HP (H Phase) with or key. Adjust the data with + or – key for 12.
4. Select NO. 10 VSC (V S Correction) with or key. Adjust the data with + or – key for 11.
5. Select NO. 14 VC (V Compression) with or key. Adjust the data with + or – key for 4.
6. Select NO. 23 POS (Pre/Over/SW) with or key. Adjust the data with + or – key for 1.
7. Select NO. 28 PRE (Preshoot Adjust) with or key. Adjust the data with + or – key for 3.
8. Select NO. 29 WP (White Peak Limiter) with or key. Adjust the data with + or – key for 1.
9. Select NO. 32 BSG (Black Str Gain) with or key. Adjust the data with + or – key for 2.
10. Select NO. 34 DCR (DC Reset) with or key. Adjust the data with + or – key for 1.
11. Select NO. 37 AF (Auto Flesh) with or key. Adjust the data with + or – key for 1.
12. Select NO. 41 RYA (R-Y/B-Y Angle) with or key. Adjust the data with + or – key for 2.
13. Select NO. 48 EWA (EW Amp) with or key. Adjust the data with + or – key for 20.
14. Select NO. 49 EWT (EW Tilt) with or key. Adjust the data with + or – key for 37.
15. Select NO. 50 EWP (EW Corner Top) with or key. Adjust the data with + or – key for 5.
16. Select NO. 51 EWB (EW Corner Bottom) with or key. Adjust the data with + or – key for 9.
17. Select NO. 55 STI (Sub Tint) with or key. Adjust the data with + or – key for 19.
18. Select NO. 57 OPT (SA Option ) with or key. Adjust the data with + or – key for 24.
19. Select NO. 58 OP2 (SA Option 2) with or key. Adjust the data with + or – key for 46.
20. Select NO. 63 SBO (Sub Bright Offset) with or key. Adjust the data with + or – key for 2.
21. Press the MENU key to turn off the Service Menu display.
NO. DATA XX OPT XXX XXXXXXXX
Figure 1. Service Menu Display
ITEM NO.
TITLE
BINARY DATA (8 bit)
DECIMAL DATA
— 4 —
Table 1. ON-SCREEN SERVICE MENU
When IC802 (EEPROM) is replaced, check the bus data to confirm they are the same as below. The shaded menu should be checked and be set up or readjusted according to the procedures described in the following pages. Initial Setup Data marked with an * should be changed from Initial Reference Data. (See page 3 for Initial Bus Data Setup.)
NO. TITLE
INITIAL REFERENCE INITIAL SETUP
RANGE OF DATA FUNCTION
DATA DATA 01 HFR 29 29 0~63 Horizontal Frequency 02 AFC 0 0 0, 1 AFC Gain & Gate 03 HP 11 12* 0~31 Horizontal Phase (Horizontal Centering) 04 VS 64 64 0~127 Vertical Size 05 VPO 32 32 0~63 Vertical Position 06 VSP 0 0 0, 1 Vertical Set Up (Sync Sensitivity) 07 VLN 17 17 0~31 Vertical Linearity 08 CRS 0 0 0~3 Cross B/W 09 GRY 1 1 0, 1 Gray Mode 10 VSC 10 11* 0~31 Vertical S Correction 11 HBR 3 3 0~7 H BLK R 12 HBL 4 4 0~7 H BLK L 13 CDM 0 0 0, 1 C D Mode 14 VC 5 4* 0~7 Vertical Compression 15 RB 0 0 0~255 Red Bias 16 GB 0 0 0~255 Green Bias 17 BB 0 0 0~255 Blue Bias 18 RD 64 64 0~127 Red Drive 19 GD 8 8 0~15 Green Drive 20 BD 64 64 0~127 Blue Drive 21 SBI 64 64 0~127 Sub Bias 22 OSD 2 2 0~3 OSD Contrast 23 POS 0 1* 0, 1 Pre/Over/SW 24 FLS 2 2 0~7 Filter System 25 CKO 3 3 0~7 Color Killer Operation 26 GYA 0 0 0, 1 G-Y Angle 27 CRG 2 2 0~3 Coring Gain 28 PRE 1 3* 0~3 Pre Shoot Adjust 29 WP 0 1* 0, 1 White Peak Limiter 30 FSW 0 0 0, 1 FBP Blanking Switch 31 VBL 0 0 0, 1 Vertical Blanking Switch 32 BSG 1 2* 0~3 Black Str Gain 33 BSS 1 1 0~3 Black Str Start 34 DCR 0 1* 0~3 DC Reset 35 YGM 1 1 0~3 Y Gamma 36 CBP 0 0 0, 1 C Bypass 37 AF 0 1* 0, 1 Auto Flesh 38 BAT 4 4 0~7 Bright ABL Threshold 39 MSD 0 0 0, 1 Mid Stop Def 40 ABL 0 0 0, 1 Auto Bright Limit 41 RYA 4 2* 0~15 R-Y/B-Y Angle 42 RAD 20 20 0~63 RF AGC Delay 43 IAS 0 0 0, 1 IF AGC 44 FMM 0 0 0, 1 FM Mute 45 FL 15 15 0~31 FM Level
— 5 —
Table 1. ON-SCREEN SERVICE MENU (Continued)
When IC802 (EEPROM) is replaced, check the bus data to confirm they are the same as below. The shaded menu should be checked and be set up or readjusted according to the procedures described in the following pages. Initial Setup Data marked with an * should be changed from Initial Reference Data. (See page 3 for Initial Bus Data Setup.)
NO. TITLE
INITIAL REFERENCE INITIAL SETUP
RANGE OF DATA FUNCTION
DATA DATA 46 VL 4 4 0~7 Video Level 47 EWD 39 39 0~63 EW DC 48 EWA 30 20* 0~63 EW Amp 49 EWT 34 37* 0~63 EW Tilt 50 EWP 7 5* 0~7 EW Corner Top 51 EWB 8 9* EW Corner Bottom 52 HSC 4 4 Horz Size Comp 53 SB 32 32 0~63 Sub Bright 54 SCO 7 7 0~31 Sub Color 55 STI 20 19* 0~31 Sub Tint 56 SSH 12 12 0~31 Sub Sharpness 57 OPT 0 24* 0~255 Option (See Note 1 page 6.) 58 OP2 0 46* 0~255 Option 2 (See Note 2 page 6.) 59 HR 24 24 0~63 OSD Horizontal Position 60 ATT 10 10 0~63 Input Level 61 WDB 32 32 0~63 Wideband 62 SPC 32 32 0~63 Spectral 63 SBO 5 2* 0~255 Sub Bright Offset 64 PCO 40 40 0~63 PIP Color 65 PTI 40 40 0~63 PIP Tint 66 PUV 24 24 0~63 PIP Top Position 67 PDV 147 147 0~255 PIP Bottom Position 68 PLH 10 10 0~63 PIP Left Position 69 PRH 101 101 0~255 PIP Right Position 70 PCN 42 42 0~63 PIP Y Level 71 PBS 15 15 0~63 PIP BGP Phase
72 DRV
64 64 0~127 Red Drive Adjustment (See Note 3 page 6.) 64 64 0~127 Blue Drive Adjustment (See Note 3 page 6.)
0 0 0~255 Red Bias Adjustment (See Note 4 page 6.)
73 0 0 0~255 Green Bias Adjustment (See Note 4 page 6.)
0 0 0~255 Blue Bias Adjustment (See Note 4 page 6.)
— 6 —
SERVICE AD JUSTMENTS (Continued)
PROGRAM CODES
The microprossesor used in this model is a multi-purpose type and is used in several different models. To ensure proper operation and the correct features for your particu­lar model, the Program Codes must be correct.
Note 1. Option Data 1 (NO. 57 OPT) should be decimal 24 (00011000 binary). See page 3 INITIAL DATA SETUP, step
18, for set up procedure. If this program code is wrong the TV will not operate properly.
Note 2. Option Data 2 (NO. 58 OP2) should be decimal 46 (00101110 binary). See page 3 INITIAL DATA SETUP, step
19, for set up procedure. If this program code is wrong the TV will not operate properly.
DRIVE / BIAS ADJUSTMENTS
Note 3. Red/Blue Drive Adjustments in Service Menu NO. 72 DRV: Adjust Red and Blue Drive Levels alternately with
1, 3, 7, and 9 keys on the remote control. (See Figure 2.) The Drive Level adjustment data will be written in the Service Menu No. 18 and 20 automatically.
1
2
3
4 5 6
7 98
RB(–)
RB(+)
BB(–)
BB(+)
(N/A)
GB(–)
(N/A)
GB(+)
(N/A)
FOR RED BIAS ADJUSTMENT
FOR BLUE BIAS ADJUSTMENT
FOR GREEN BIAS ADJUSTMENT
Figure 2.
Figure 3.
1
2
3
4 5 6
7 98
RD(–)
RD(+)
BD(–)
BD(+)
(N/A)
(N/A)
(N/A)
(N/A)
(N/A)
FOR RED DRIVE ADJUSTMENT
FOR BLUE DRIVE ADJUSTMENT
BIT FUNCTION
DATA
01
0 ~ 2 NOT USED — 3 CLOCK NONE YES 4 COMB FILTER NONE YES 5 NOT USED
00: NONE
6, 7 SURROUND
01: YES 10: — 11: —
Note 4. Red/Green/Blue Bias Adjustments in Service Menu NO. 73: Adjust each Bias Level with 1, 3, 4, 6, 7, or 9 key on
the remote control. (See Figure 3.) The Bias Level adjust­ment data will be written in the Service Menu No. 15 ~ 17 automatically.
BIT FUNCTION
DATA
01
0
SHIPPING CONDITION
NORMAL COOL
OF COLOR ENHANCER 1 COLOR ENHANCER NONE YES 2 INITIAL CH & XDS NONE YES 3 AUDIO OUT & SP MENU NONE YES 4 PIP NONE YES 5 AV INPUTS 1 SET 2 SETS 6 BASS & TREBLE / TONE BASS & TR TONE 7 NOT USED
——
— 7 —
ANTENNA CONNECTIONS
This receiver is designed for UHF/VHF reception. A 75 ohm terminal is provided for UHF and VHF receptions. When connecting a CATV antenna system, connect the 75 ohm coaxial cable directly to the 75 ohm terminal. For 300 ohm VHF antenna, use an adapter (not included with the TV set).
CIRCUIT PROTECTION
Fuse F601 (4A) is included in the AC line. This fuse must be replaced with the proper fuse (see Parts List).
+B VOL T AGE CHECK
Connect Voltmeter + lead to TJ1 130V and – lead to ground (TE7). Connect receiver to AC 120V line. Tune receiver to an active channel. Reset the picture controls to the FACTORY PRESET levels (press remote control RESET key twice). Voltage must measure between +128.0V and +132.0V. If the voltage is out of this range, the power circuit must be checked. No +B adjustment is provided on this chassis.
HORIZONT AL WIDTH AD JUSTMENT
1. Tune receiver to an active channel.
2. Check the picture for proper width. If width is not correct, perform steps 3 ~ 6.
3. Turn off the receiver and disconnect the AC power cord (120V AC line).
4. While pressing the MENU key, reconnect the AC power cord. The Service Menu display will now appear.
5. Select NO. 47 EWD (EW DC) with or key.
6. Adjust the data with + or – key for proper width.To turn off the Service Menu display, press the MENU key.
HORIZONTAL CENTERING ADJUSTMENT
1. Tune receiver to an active channel.
2. Check that picture is in the horizontal center of TV screen. If picture is not centered horizontally, perform steps 3 ~ 6.
3. Turn off the receiver and disconnect the AC power cord.
4. While pressing the MENU key, reconnect the AC power cord. The Service Menu display will now appear.
5. Select NO. 03 HP (Horizontal Phase) with or key.
6. Adjust the data with + or – key for horizontal center. To turn off the Service Menu display, press the MENU key.
VERTICAL SIZE ADJUSTMENT
1. Tune receiver to an active channel.
2. Check the vertical size of the picture. If the vertical size is too large or small, perform steps 3 ~ 6.
3. Turn off the receiver and disconnect the AC power cord.
4. While pressing the MENU key, reconnect the AC power cord. The Service Menu display will now appear.
5. Select NO. 04 VS (Vertical Size) with or key.
6. Adjust the data with + or – key for full scan. To turn off the Service Menu display, press the MENU key.
VERTICAL CENTERING ADJUSTMENT
1. Tune receiver to an active channel.
2. Check that picture is in the center of TV screen. If picture center is too low, change resistor R513 from 1K ohm 1/2W to 470 ohm 1W. If picture center is too high, remove resistor R513 (1K ohm, 1/2W).
VCO AD JUSTMENT
Note: VCO must be adjusted after IC101 (Signal Processor),
IC802 (EEPROM) or T151 (VCO Coil) is replaced.
1. Tune receiver to an active channel.
2. Set the picture controls to the Sports level.
3. Connect digital voltmeter + lead to pin 58 of IC101 and – lead to ground (TE 7).
4. Confirm a reading of 3.6 ± 0.2 VDC.
5. If voltage is out of specifications adjust T151 for
3.6 ± 0.2 VDC.
RF AGC ADJUS TMENT
1. Tune receiver to strongest VHF station in your area.
2. Set contrast and brightness controls for maximum.
3. Turn off the receiver and disconnect the AC power cord (120V AC line).
4. While pressing the MENU key, reconnect the AC power cord. The Service Menu display will now appear.
5. Select NO. 42 RAD (RF AGC Delay) with or key.
6. Adjust the data with + or – key in the direction which causes snow to appear; then in the opposite direction until the snow just disappears.
7.To turn off the Service Menu display, press the MENU key.
VIDEO LEVEL
1. Connect color bar generator to antenna terminals.
2. Turn off the receiver and disconnect the AC power cord (AC 120V line).
3. Connect oscilloscope to TP16 (Q202 emitter) and ground.
4. While pressing the Menu key, reconnect the AC power cord. The Service Menu will now appear.
5. Select NO. 46 VL (Video Level) with the or key.
6. Adjust the + or – key for an oscilloscope reading of 1.0 ±
0.1 VP-P at TP16. Press the MENU key to turn off the Service Menu display.
CAUTION
FOR CONTINUED PROTECTION AGAINST A RISK OF FIRE, REPLACE ONLY WITH THE SAME TYPE 4A, 125V FUSE.
ATTENTION : POUR MAINTENIR LA PRO­TECTION CONTRE LES RISQUES D’ INCENDIE UTILISER UN FUSIBLE DE RECHANGE DE MEME TYPE 4A, 125V.
1.0 ± 0.1 VP-P
Figure 4.
4A 125V
SERVICE AD JUSTMENTS (Continued)
— 8 —
GRA Y SCALE ADJUS TMENT
1. Set the picture controls to the Sports levels or Reset (use MENU key and or key or RESET key).
2. Turn off the receiver and disconnect the AC power cord (120V AC line).
3. While pressing the MENU key, reconnect the AC power cord. The Service Menu display will now appear.
4. Select NO. 15 RB (Red Bias), NO. 16 GB (Green Bias), and NO. 17 BB (Blue Bias) with ▲ or ▼ key and set each data to 0 with + or – key.
5. Select NO. 18 RD (Red Drive) and NO. 20 BD (Blue Drive) with or key and set each data to 64 with + or – key.
6. Set NO. 19 GD (Green Drive Reduction) data to 8, NO. 53 SB (Sub-Brightness) data to 32, NO. 54 SCO (Sub-Color) data to 7, NO. 55 STI (Sub-Tint) to 19, and NO. 56 SSH (Sub-Sharpness) data to 12 with ▲ or ▼, and + or – keys.
7. Turn Screen Control (T402) to minimum (fully counter­clockwise).
8. Select the Service Menu NO. 73 (Bias Adjustments) with or key.
9. Advance Screen Control (T402) clockwise to obtain just visible one color line. If line does not appear, place this control to maximum (fully clockwise).
10. Raise each Bias Level with 3, 6, and 9 keys to obtain just visible white line. (See Figure 5.)
11. Select the Service Menu NO. 72 DRV (Drive Adjustments) with or key.
12. Adjust Red and Blue Drive Levels alternately with 1, 3, 7, or 9 key to produce normal black and white picture in highlight areas. (See Figure 6.)
13. Check for proper grayscale at all brightness levels. To turn off the Service Menu display, press the MENU key.
Note: If Grayscale Adjustment is made after picture tube
replacement, check Brightness Level Adjustment.
FOCUS ADJUSTMENT
Adjust focus control (T402) for well defined scanning lines.
BRIGHTNESS LEVEL ADJUSTMENT
Note: Grayscale, RF AGC, Video Level, and High Voltage Check
must be adjusted before attempting Brightness Level Adjustment.
1. Connect a color-bar generator to the antenna terminals.
2. Switch the generator to the crosshatch pattern.
3. Reset the picture controls to the Sports levels.
4. Connect voltmeter (high impedance) + lead to terminal
TP51 and – lead to terminal TP50 on main board. Set
voltmeter for 1.5V ~ 3V range.
5. Turn off the receiver and disconnect the AC power cord.
6. While pressing the MENU key, reconnect the AC power cord. The Service Menu display will now appear.
7. Select NO. 53 SB (Sub Brightness) with ▲ or ▼ key.
8. Adjust the data with + or – key for 820mVDC.
9. Press the MENU key to turn off the Service Menu display.
10. Check brightness level on every active channel, readjust (repeat steps 5 ~ 9), if necessary.
Note: Do not set to excessive brightness level, otherwise
the contrast level will be suppressed.
HIGH VOL T AGE HOLD-DOWN TEST
Every time the receiver is serviced, the HIGH VOLTAGE HOLD-DOWN circuit must be tested for proper operation by following these steps:
1. Connect receiver to 120V AC line. Tune receiver to active
channel. Reset the picture controls to the Sports levels.
2. Check that the voltage measured between TP7 and TE7
(ground side) is within 16.5 VDC to 21 VDC. If the voltage is out of this range, the Hold-Down Circuit must be checked.
3. Connect a DC Voltage supply to TP7 and TE7 through a
100 ohm 1/4W resistor. Adjust the DC voltage to 23 VDC. The receiver should shutdown, losing raster and sound. Then the receiver should turn off automatically. This reaction indicates that the Hold-Down circuit is function­ing properly. If the receiver does not shutdown, a malfunction is indicated and its cause must be found and corrected.
4. To obtain picture again, remove the DC Supply and wait
a few minutes. Now turn on the receiver.
HIGH VOL T AGE CHECK
Note: +B (+130V) Voltage Check and Grayscale Adjustment
must be completed before attempting High Voltage Check.
1. Connect high voltage voltmeter – lead to ground, and
connect + lead to anode of picture tube.
2. Tune receiver to an active channel and confirm TV is
operating properly.
3. Eliminate the beam current by adjusting the contrast and
brightness controls to minimum.
4. Confirm high voltage is within 31.0 KV and 33.0 KV. If
reading is not within range, check horizontal circuit.
No high-voltage adjustment is provided on this chassis.
1
2
3
4 5 6
7 98
RB(–)
RB(+)
BB(–)
BB(+)
(N/A)
GB(–)
(N/A)
GB(+)
(N/A)
FOR RED BIAS ADJUSTMENT
FOR BLUE BIAS ADJUSTMENT
FOR GREEN BIAS ADJUSTMENT
Figure 5. Remote Control Number keys’ functions in
Service Menu NO. 73
1
2
3
4 5 6
7 98
RD(–)
RD(+)
BD(–)
BD(+)
(N/A)
(N/A)
(N/A)
(N/A)
(N/A)
Figure 6. Remote Control Number keys’ functions in
Service Menu NO. 72 DRV
FOR RED DRIVE ADJUSTMENT
FOR BLUE DRIVE ADJUSTMENT
— 9 —
SOUND ADJUSTMENT
1. Connect a color-bar generator to the antenna terminals with audio signal of 1KHz at 100% modulation.
2. Set the picture controls to the Sports levels
3. Connect oscilloscope + lead to TP21 (pin 75 of IC101) and – lead to ground.
4. Turn off the receiver and disconnect the AC power cord (AC 120V line).
5. While pressing the Menu key, reconnect the AC power cord. The Service Menu will now appear.
6. Select NO. 45 FL (FM Level) with the or key.
7. Adjust the data with the + or – key for an oscilloscope reading of 0.693 ± 10% VP-P at TP21.
8. Press the MENU key to turn off the Service Menu display and disconnect the oscilloscope from the chassis.
MULTI-SOUND SECTION ADJUSTMENTS
Note: Multi-Sound Section must be adjusted after
IC101 (Signal Processor), IC3401 (MTS Decoder), , or IC802 (EEPROM) is replaced.
INPUT LEVEL ADJUSTMENT
1. Connect a signal to the antenna terminals with audio of 1 KHZ 100% modulation.
2. Turn off the receiver and disconnect the AC power cord (AC 120V line).
3. Connect voltmeter (RMS) to TP317 and ground.
4. While pressing the Menu key, reconnect the AC power cord. The Service Menu will now appear.
5. Select NO. 60 ATT (Attenuation) with the or key.
6. Adjust the + or – key for a voltmeter reading of 400 ± 20 mVrms at TP317.
SEP ARA TION AD JUSTMENT
7. Turn off the receiver and disconnect the AC power cord (AC 120V line).
8. Connect oscilloscope CH1 to TP317 and CH2 to TP318 and ground.
9. Connect an MTS TV/Stereo generator to antenna terminal.
10. While pressing the Menu key, reconnect the AC power cord. The Service Menu will now appear.
11. Select pilot, 300Hz audio frequency and Left modulating signal.
12. Select NO. 61 WDB (Wideband) with the ▲ or ▼ key.
13. Adjust the + or – key for minimum low frequencies at TP317. (See Figure 8.)
14. Select 4 KHz audio frequency and Right modulating signal.
15. Select NO. 62 SPC (Spectral) with the or key.
16. Adjust the + or – key for minimum high frequencies at TP318. (See Figure 8.)
Repeat adjustments (steps 11–16) until no further decreases in amplitude can be obtained. Press the MENU key to turn off the Service Menu display.
PURITY AND CONVERGENCE ADJUSTMENTS
Purity and Convergence have been aligned at the factory. No re-alignment is necessary.
Figure 8. Separation Adjustments
0.693 ± 10% VP-P
Figure 7.
Minimize L leakage
TP317 (R)
300Hz
Minimize R leakage
TP318 (L)
4KHz
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