Sharp 21GT-22 User manual

1
21GT-22
WARNING
The chassis in this receiver is partially hot. Use an isolation transformer between the line cord plug and power
receptacle, when servicing this chassis. To prevent electric shock, do not remove cover. No user – serviceable
parts inside. Refer servicing to qualified service personnel.
SERVICE MANUAL
In the interests of user-safety (Required by safety regulations in some countries) the set should be restored
to its original condition and only parts identical to those specified should be used.
MODEL 21GT-22
SHARP CORPORATION
COLOUR TELEVISION
Chassis No. GA-1
Page
CONTENTS
»SPECIFICATIONS .............................................2
»IMPORTANT SERVICE NOTES ........................2
»ADJUSTMENT PRECAUTIONS........................3
»MEMORY MAP ................................................11
»GA1 HOTEL MODE APPLICATION ................15
»TROUBLE SHOOTING TABLE........................15
»SOLID STATE DEVICE BASE DIAGRAM .......18
»WAVEFORMS..................................................19
»CHASSIS LAYOUT..........................................20
»BLOCK DIAGRAM...........................................21
»DESCRIPTION OF SCHEMATIC DIAGRAM ..25
»SCHEMATIC DIAGRAM
ËMAIN UNIT ................................................... 26
ËCRT UNIT.....................................................28
Page
ËHEADPHONE UNIT .....................................28
ËMONO BILINGUAL UNIT.............................29
»PRINTED WIRING BOARD ASSEMBLIES .....30
»REPLACEMENT PARTS LIST
ËELECTRICAL PARTS
MAIN UNIT ...................................................36
CRT UNIT.....................................................39
HEADPHONE UNIT .....................................39
MONO BILINGUAL UNIT.............................39
ËSUPPLIED ACCESSORIES.........................40
ËPACKING PARTS.........................................40
ËCABINET PARTS .........................................41
»PACKING OF THE SET...................................42
FEATURES
ËPAL B/G
ËNTSC(AV Thru)
ËFull Auto Channel Preset and Auto Channel Skip
Ë100 CH Program Memory
ËCATV (Hyper Band) Ready
ËAVL (Sound Keeper) Function
ËHigh Contrast Picture (Black Stretch Circuit)
ËON Timer/Sleep Timer/Reminder Timer
ËFavourite Channel
ËBlue Back Noise Mute
ËFront AV In (Front AV Priority)
ËRear AV In/Out Terminals
ËColour-Comb Filter (NTSC AV In)
ËHotel Mode
ËFront Headphone Jack
ËEnglish/Thai Language OSD
ËMono Bilingual
SX2U121GT-22/

2-1 2-2
2
21GT-22
SPECIFICATIONS
Convergence .................................................................................Self Converging System Focus .........................................................................Electrostatic Focus High Bi-Potential Sweep Deflection................................................................................................... Magnetic Intermediate Frequencies
Picture IF Carrier ............................................................................................... 38.9 MHz Sound IF Carrier Frequency
5.74 MHz ...................................................................................................... 33.16 MHz 5.5 MHz .......................................................................................................... 33.4 MHz
Colour Sub-Carrier Frequency ....................................................................... 34.47 MHz
Power Input.................................................................................... AC110 - 240V, 50/60 Hz Power Consumption .....................................................................................................84 W Audio Power Output Rating......................................................................... 5.0 W (at Max.) Speaker
Size ..............................................................................................5 ×9 cm Elliptic (2 pcs) Voice Coil Impedance......................................................................... 16 ohms at 400 Hz
Aerial Input Impedance
VHF/UHF....................................................................................... 75 ohm Unbalanced
Receiving Channels (PAL-B/G)
»VHF..................................................................................................... E2 thru E12 »UHF .................................................................................................. E21 thru E69
Receiving Frequency
»VHF-Channels.................................................................... 48.25 thru 463.25 MHz »UHF-Channels ................................................................. 471.25 thru 863.25 MHz
Dimensions ..............................................................................................Width: 506.5 mm
Height: 476.0 mm
Depth: 477.5 mm
Weight (Approx.): 20.5 kg
Cabinet Material ................................................................................................. All Plastics
Specifications are subject to change without prior notice.
IMPORTANT SERVICE NOTES
Maintenance and repair of this receiver should be done by
qualified service personnel only.
SERVICING OF HIGH VOLTAGE SYSTEM AND PICTURE TUBE When servicing the high voltage system, remove static charge from it by connecting a 10k ohm Resistor in series with an insulated wire (such as a test probe) between picture tube dag and 2nd anode lead. (AC line cord should be disconnected from AC outlet.) 1. Picture tube in this receiver employs integral implosion protection. 2. Replace with tube of the same type number for continued safety. 3. Do not lift picture tube by the neck. 4. Handle the picture tube only when wearing shatterproof goggles and after
discharging the high voltage completely
X-RAY This receiver is designed so that any X-Ray radiation is kept to an absolute minimum. Since certain malfunctions or servicing may produce potentially hazardous radiation with prolonged exposure at close range, the following precautions should be observed: 1. When repairing the circuit, be sure not to increase the high voltage to more
than 28.0 kV (at beam 0

3
3-1 3-2
21GT-22
ADJUSTMENT PRECAUTIONS
This model’s setting are adjusted in two different ways: though the I2C bus control and in the conventional analog manner. The adjustments via the I2C bus control include preset-only items and variable data. CAUTION : Make sure TV Set is in "Normal Condition" before switch to Service Mode for
adjustment.
1. Setting the service mode by the microprocessor.
1Make a short-circuit 137 and 138 for a second and release to switch to the service mode
position and the microprocessor is in input mode. (Adjustment through the I2C bus con- trol). (Use JWS Key to set as well).
2Press the CH DOWN / UP key on the remote controller to get ready to select the mode
one by one.
3Press the CH DOWN / UP key on the remote controller to select the modes reversibly
one by one.
4Using the VOLUME UP/ DOWN key on the remote controller, the data can be modified. 5Make a short-circuit 137 and 138 for a second and release to switch to the normal mode
(OFF) position and the microprocessor is in out of the service mode.
2. Factory Presetting.
1Make a short-circuit JA137 and JA138, then turn ON the main power and release to
switch to Service Mode. Initial values are automatically preset, only when a new EEPROM is used (Judge with the first 4 bytes).
2The initial data are preset as listed in pages 4-6. 3Make sure the data need modify or not (Initial data).
Note: Once the chassis has been assembly together and ready to be POWER ON for the
FIRST TIME, make sure to make a short-circuit 137 and 138 switch to the service mode position first and then turn on the main power switch. (See 2-1 above). Precaution: If haven’t done this initiation, it may possibly generate excessive Beam current.
3. For reference please check with memory map
(GA1 Series type RH-iX3368CE)
ËSERVICE MODE (1)In the Service Mode, Key is used to select the mode in the following order.
AGC &
GEOMETRIC
MODE
↓
AGCTAKE OVER POINT (AGC)
↓
VERTICAL SLOPE (V-LIN)
↓
VERTICAL AMP (V-AMP)
↓
VERTICAL SHIFT (V-CENT)
↓
HORIZONTAL SHIFT (H-CENT)
↓
EAST-WEST WIDTH (H-SIZE)
↓
HORIZONTAL PARALLELOGRAM (EW//)
↓
EAST-WEST PARABOLA/WIDTH (PARA)
↓
EAST-WEST UPPER COR.PB (COR(U))
↓
EAST-WEST LOWER COR. PB (COR(L))
↓
EAST WEST TRAPEZIUM (TRAPE)
↓
HORIZONTAL BOW (HB)
↓
S-CORRECTION (S-COR)
WHITE POINT
ADJ.
MODE
↓
W.P RED STD.W.T. (DRI-RS)
↓
W.P. GREEN STD.W.T.(DRI-GS)
↓
W.P.BLUE STD.W.T. (DRI-BS)
↓
W.P. RED COOL W.T.(DRI-RC)
↓
W.P. GREEN COOL W.T.(DRI-GC)
↓
W.P. BLUE COOL W.T.(DRI-BC)
↓
W.P. RED WARM W.T.(DRI-RW)
↓
W.P. GREEN WARM W.T.(DRI-GW)
↓
W.P. BLUE WARM W.T. (DRI-BW)
SUB
ADJ.
MODE
↓
MAX VOLUME (SUB-VOL)
↓
SUB CONTRAST (SUB-CON)
↓
SUB COLOUR (SUB-COL)
↓
SUB BRIGHTNESS (SUB-BRI)
↓
SUB TINT (SUB-TINT)
↓
SUB SHARPNESS (SUB-SHP)
↓
MAX HOTEL VOLUME (HTL-VOL)
↓
HOTEL PROGRAM NO(HTL-PRG)
↓
OSD RGB REFERENCE (RGB)
↓
BLACK LEVEL OFFSET R(CUT-R)
↓
BLACK LEVEL OFFSET G(CUT-G)
↓
CATHODE DRIVE LEVEL(CDL)
FORWARD : CH DOWN KEY REVERSE : CH UP KEY * ( ) means OSD display.
FORWARD : CH DOWN KEY REVERSE : CH UP KEY
AGC &
GEOMETRIC
MODE
WHITE POINT
ADJ.
MODE
SUB
ADJ.
MODE
Y-DELAY
ADJ.
MODE
MISC.
OPTION
MODE
IC
OPTION
MODE
OFFSET
ADJ.
MODE

4-1 4-2
4
21GT-22
Y-DELAY
ADJ.
MODE
↓
Y-D TIME FOR PAL (TV) (DL-PT)
↓
Y-D TIME FOR SECAM (TV) (DL-ST)
↓
Y-D TIME FOR N358 (TV) (DL-3T)
↓
Y-D TIME FOR N443 (TV) (DL-4T)
↓
Y-D TIME FOR B/W (TV) (DL-TV)
↓
Y-D TIME FOR PAL (AV) (DL-PA)
↓
Y-D TIME FOR SECAM (AV) (DL-SA)
↓
Y-D TIME FOR N358 (AV) (DL-3A)
↓
Y-D TIME FOR N443(AV) (DL-4A)
↓
Y-D TIME FOR B/W (AV) (DL-AV)
*(Y-D :Y-DELAY)
OFFSET
ADJ.
MODE
↓
COLOUR OFFSET (PAL) (COL-OP)
↓
COLOUR OFFSET (SECAM) (COL-OS)
↓
COLOUR OFFSET (NTSC358) (COL-O3)
↓
COLOUR OFFSET (NTSC443) (COL-O4)
↓
SHARPNESS OFFSET (PAL) (SHP-OP)
↓
SHARPNESS OFFSET (SECAM) (SHP-OS)
↓
SHARPNESS OFFSET (NTSC358) (SHP-O3)
↓
SHARPNESS OFFSET (NTSC443) (SHP-O4)
IC
OPTION
MODE
↓
VERTICAL SCAN DISABLE(VSD)
↓
BLACK STRETCH (BKS)
↓
AUTO VOLUME LEVELING(AVL)
↓
FAST FILTER IF-PLL(FFI)
↓
ENABLE VERTICAL GUARD (EVG)
↓
EHT TRACKING MODE (EHT)
↓
OVERSCAN SWITCH OFF(OSO)
↓
AUTO COLOUR LIMIT(ACL)
↓
FORCED COLOUR LIMIT(FCO)
MISC.
OPTION
MODE
↓
SOUND SYSTEM M (S-M)
↓
SOUND SYSTEM DK (S-DK)
↓
SOUND SYSTEM I (S-I)
↓
SOUND SYSTEM BG (S-BG)
↓
PLAYBACK SECAM (P-SECAM)
↓
FE (RF) NTSC 3.58 (F-N358)
↓
FE (RF) NTSC 4.43 (F-N443)
↓
FE (RF) SECAM (F-SECAM)
↓
VIDEO MUTE AT IDENT LOSS (VMI)
↓
VIDEO MUTE AT PROGRAM
/SOURCE CHANGE (VMC)
↓
HOTEL MODE (HTL)
↓
REDUCED FM DEMODULATION
GAIN FOR BTSC SIGNAL (BTSC)
↓
A
A
↓
NUMBER OF EXT AV SOURCE (AV)
↓
FM WINDOW SELECTION (FMWS)
↓
SOUND MUTE BIT 0 (SM0)
↓
SOUND MUTE BIT 1 (SM1)
↓
THAI LANGUAGE (THA)
↓
ARABIC LANGUAGE (ARA)
↓
MALAY LANGUAGE (MAL)
↓
CHINESE LANGUAGE (CHI)
↓
FRENCH LANGUAGE (FRE)
↓
RUSSIAN LANGUAGE (RUS)
↓
FORCED V-SYNC SLICING LEVEL(FSL)
↓
SYNC OF OSD (HP2)
↓
TUNER SELECTION (CPT)
↓
B
↓
BILINGUAL(BIL)
↓
IF AGC SPEED BIT 0 (AGC0)
↓
IF AGC SPEED BIT 1 (AGC1)
↓
FOATime Constant-RF (FOA-FE)
↓
FOB Time Constant-RF (FOB-FE)
↓
FOATime Constant-AV (FOA-AV)
↓
FOB Time Constant-AV (FOB-AV)
↓
LED BLINK SPEED (LED-F)
↓
VOLUME CONTROL TABLE (MSA)
↓
OUTPUT VERTICAL GUARD (NDF)
B
Direct Key-in for Service Item in Service Mode.
RC COMMAND SERVICE-ITEM
FUNCTION AGC
CONTRAST DOWN V-LIN
COLOUR DOWN V-AMP
BRIGHTNESS DOWN V-CENT
TINT DOWN H-CENT
SHARPNESS DOWN EW / /
SYSTEM HB
BLUEBACK S-COR
TIMER SUB-VOL
CONTRAST UP SUB-CON
COLOUR UP SUB-COL
BRIGHTNESS UP SUB-BRI
TINT UP SUB TINT
SHARPNESS UP SUB-SHP
CHANNEL 1 DRI-GS CHANNEL 4 DRI-BS CHANNEL 7 CUT-R
CHANNEL FLASHBACK CUT-G

5
5-1 5-2
21GT-22
After short JA137 & 138, and turn on the main power switch, read data from E2PROM address 00H ~ 03H, and compare to the list below, if different, initialize the E2PROM.
Address : Data Address : Data
00H : 55H 02H : 43H 01H : 4FH 03H : A1H
EEPROM ITEMS OSD DATA LENGTH
INITIAL DATA FIX/ADJ
REMARK
AGC TAKE OVER POINT AGC 0~63 14 ADJ VERTICAL SLOPE V-LIN 0~63 32 ADJ VERTICAL AMPLITUDE V-AMP 0~63 32 ADJ VERTICAL SHIFT V-CENT 0~63 32 ADJ HORIZONTAL SHIFT H-CENT 0~63 32 ADJ EAST-WEST WIDTH H-SIZE 0~63 32 *FIX HORIZONTAL PARALLELOGRAM EW// 0~63 32 *FIX EAST-WEST PARABOLA/WIDTH PARA 0~63 32 *FIX EAST-WEST UPPER CORNER PARABOLA COR (U) 0~63 32 *FIX EAST-WEST LOWER CORNER PARABOLA COR (L) 0~63 32 *FIX EAST-WEST TRAPEZIUM TRAPE 0~63 32 *FIX HORIZONTAL BOW HB 0~63 32 *FIX S-CORRECTION S-COR 0~63 0 ADJ *3 WHITE POINT RED STD WHITE TEMP DRI-RS 0~63 32 *FIX WHITE POINT GREEN STD WHITE TEMP DRI-GS 0~63 32 ADJ WHITE POINT BLUE STD WHITE TEMP DRI-BS 0~63 32 ADJ WHITE POINT RED COOL WHITE TEMP DRI-RC 0~63 25 *FIX WHITE POINT GREEN COOL WHITE TEMP DRI-GC 0~63 32 ADJ (DRI-GS)- 7 DATA WHITE POINT BLUE COOL WHITE TEMP DRI-BC 0~63 32 ADJ
SAME AS (DRI-BS) DATA
WHITE POINT RED WARM WHITE TEMP DRI-RW 0~63 32 *FIX WHITE POINT GREEN WARM WHITE TEMP DRI-GW 0~63 32 ADJ (DRI-GS)-7 DATA WHITE POINT BLUE WARM WHITE TEMP DRI-BW 0~63 32 ADJ (DRI-BS)-7 DATA MAX VOLUME SUB-VOL 0~63 63 *FIX SUB CONTRAST SUB-CON 0~63 63 *FIX SUB COLOUR SUB-COL 0~63 32 ADJ *4 SUB BRIGHTNESS SUB-BRI 0~63 32 ADJ SUB TINT SUB-TINT 0~63 32 ADJ SUB SHARPNESS SUB-SHP 0~63 32 (20) *FIX MAX HOTEL VOLUME HTL-VOL 0~63 32 *FIX HOTEL PROGRAM NUMBER HTL-PRG
0~99 OR>99FOR NONE
255 *FIX
OSD RGB REFERENCE RGB 0~15 15 *FIX BLACK LEVEL OFF-SET R CUT-R 0~63 32 ADJ BLACK LEVEL OFF-SET G CUT-G 0~63 32 ADJ CATHODE DRIVE LEVEL CDL 0~15 0 ADJ *2 Y-DELAY TIME FOR PAL(TV) [YD] DL-PT 0~15 12 *FIX Y-DELAY TIME FOR SECAM(TV) [YD] DL-ST 0~15 15 *FIX Y-DELAY TIME FOR N358 (TV) [YD] DL-3T 0~15 12 *FIX Y-DELAY TIME FOR N443 (TV) [YD] DL-4T 0~15 12 *FIX Y-DELAY TIME FOR B/W (TV) [YD] DL-TV 0~15 12 *FIX Y-DELAY TIME FOR PAL (AV) [YD] DL-PA 0~15 12 *FIX Y-DELAY TIME FOR SECAM (AV) [YD] DL-SA 0~15 15 *FIX Y-DELAY TIME FOR N358 (AV) [YD] DL-3A 0~15 12 *FIX Y-DELAY TIME FOR N443 (AV) [YD] DL-4A 0~15 12 *FIX Y-DELAY TIME FOR B/W (AV) [YD] DL-AV 0~15 12 *FIX COLOUR OFFSET (PAL) COL-OP 0~15 8 *FIX COLOUR OFFSET (SECAM) COL-OS 0~15 8 *FIX COLOUR OFFSET (NTSC358) COL-03 0~15 4 *FIX COLOUR OFFSET (NTSC443) COL-O4 0~15 4 *FIX SHARPNESS OFFSET (PAL) SHP-OP 0~15 8 *FIX SHARPNESS OFFSET (SECAM) SHP-OS 0~15 4 *FIX
NOTE : 1) *FIX: PLEASE DO NOT CHANGE FIXED DATA WITHOUT SPECIFIC INSTRUCTION.
Please set the EEPROM initial data according to the value in parenthesis ( ) before adjustment.
2) *2: CDLADJUST = 7 3) *3: S-COR ADJUST = 20
4) *4: After SUB-COLOURADJUSTMENT, ADD 6 STEPS INTO THE DATA OF SUB-COL.
NEW SUB-COL=SUB-COL DATAOF 75% WHITE & RED PORTIONS AT SAME LEVEL +6
STEPS.
EEPROM ITEMS OSD DATA LENGTH
INITIAL DATA FIX/ADJ
REMARK
SHARPNESS OFFSET (NTSC358) SHP-O3 0~15 12 *FIX SHARPNESS OFFSET (NTSC443) SHP-O4 0~15 8 *FIX VERTICAL SCAN DISABLE VSD
0(DISABLE)/1(ENABLE)
0*FIX
BLACK STRETCH BKS
0(DISABLE)/1(ENABLE)
1*FIX
AUTOMATIC VOLUME LEVELING AVL
0(DISABLE)/1(ENABLE)
1*FIX
FAST FILTER IF-PLL FFI
0(DISABLE)/1(ENABLE)
0*FIX
ENABLE VERTICAL GUARD (RGB BLANKING) EVG
0(DISABLE)/1(ENABLE)
1*FIX
EHT TRACKING MODE (HCO) EHT
0(DISABLE)/1(ENABLE)
1*FIX
OVERSCAN SWITCH OFF OSO
0(DISABLE)/1(ENABLE)
0*FIX
AUTO COLOUR LIMIT ACL
0(DISABLE)/1(ENABLE)
0*FIX
FORCED COLOUR LIMIT FCO
0(DISABLE)/1(ENABLE)
0*FIX
SOUND SYSTEM M S-M
0(DISABLE)/1(ENABLE)
0*FIX
SOUND SYSTEM DK S-DK
0(DISABLE)/1(ENABLE)
1 (0) *FIX
SOUND SYSTEM I S-I
0(DISABLE)/1(ENABLE)
1 (0) *FIX
SOUND SYSTEM BG S-BG
0(DISABLE)/1(ENABLE)
1*FIX
PLAYBACK SECAM P-SECAM
0(DISABLE)/1(ENABLE)
1 (0) *FIX
FE (RF) NTSC 3.58 F-N358
0(DISABLE)/1(ENABLE)
0*FIX
FE (RF) NTSC 4.43 F-N443
0(DISABLE)/1(ENABLE)
1 (0) *FIX
FE (RF) SECAM F-SECAM
0(DISABLE)/1(ENABLE)
1 (0) *FIX
VIDEO MUTE AT IDENT LOSS VMI
0(DISABLE)/1(ENABLE)
1*FIX
VIDEO MUTE AT PROGRAM/SOURCE CHANGE
VMC
0(DISABLE)/1(ENABLE)
1*FIX
HOTEL MODE HTL
0(DISABLE)/1(ENABLE)
0*FIX
REDUCED FM DEMODULATOR GAIN FOR BTSC SIGNAL
BTSC
0(DISABLE)/1(ENABLE)
0*FIX
NUMBER OF EXTERNALAV SOURCE AV
0 FOR1 AV/1 FOR 2AV
1 (0) *FIX
FM WINDOW SELECTION FMWS
0(DISABLE)/1(ENABLE)
0*FIX
SOUND MUTE BIT 0 SM0
0(DISABLE)/1(ENABLE)
1*FIX
SOUND MUTE BIT 1 SM1
0(DISABLE)/1(ENABLE)
0*FIX
THAI LANGUAGE THA
0(DISABLE)/1(ENABLE)
0 (1) *FIX
ARABIC LANGUAGE ARA
0(DISABLE)/1(ENABLE)
1 (0) *FIX
MALAY LANGUAGE MAL
0(DISABLE)/1(ENABLE)
1 (0) *FIX
CHINESE LANGUAGE CHI
0(DISABLE)/1(ENABLE)
1 (0) *FIX
FRENCH LANGUAGE FRE
0(DISABLE)/1(ENABLE)
1 (0) *FIX
RUSSIAN LANGUAGE RUS
0(DISABLE)/1(ENABLE)
1 (0) *FIX
FORCED V-SYNC SLICING LEVEL FSL
0(DISABLE)/1(ENABLE)
0*FIX
SYNC OF OSD HP2
0(DISABLE)/1(ENABLE)
0*FIX
TUNER SELECTION (0:SHARP/ALPS;1:MURATA) CPT 0(DISABLE)/1(ENABLE) 0 (1)
*FIX
BILINGUAL BIL
0(DISABLE)/1(ENABLE) 0 (1)
*FIX
IF AGC SPEED BIT 0 AGC0
0(DISABLE)/1(ENABLE)
1*FIX
IF AGC SPEED BIT 1 AGC1
0(DISABLE)/1(ENABLE)
0*FIX
PHI-1 TIME CONSTANT (RF) FOA-FE
0(DISABLE)/1(ENABLE)
0*FIX
PHI-1 TIME CONSTANT (RF) FOB-FE
0(DISABLE)/1(ENABLE)
0*FIX
PHI-1 TIME CONSTANT (OFF AIR) FOA-AV
0(DISABLE)/1(ENABLE)
1*FIX
PHI-1 TIME CONSTANT (OFF AIR) FOB-AV
0(DISABLE)/1(ENABLE)
1*FIX
LED BLINK SPEED LED_F
0(DISABLE)/1(ENABLE)
0 (1) *FIX
VOLUME CONTROL PWM TABLE MSA
0(DISABLE)/1(ENABLE)
0 (1) *FIX
OUTPUT VERTICAL GUARD NDF
0(DISABLE)/1(ENABLE)
0 (1) *FIX