Sharp 14GT15 User manual

1
14GT15
14GT20
SHARP CORPORATION
SERVICE MANUAL
14GT15
14GT20
MODELS
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.
FEATURE
ËFavorite Channel
ËFull Auto Channel Preset and Auto Channel Skip
Ë100-CH Program Memory
ËCATV(Hyper Band) Ready <Used Frequency Synthesizer
Tuner>
ËAVL(Sound Keeper) Function
ËBlack Stretch Circuit
ËOn Timer/Sleep Timer/Reminder Timer
ËBlue Back Noise Mute
ËFrontAV-In (14GT-20 Only)
ËRearAV-In/Out Terminals
ËColour Comb Filter (NTSC Only)
ËHigh Contrast Picture
ËHotel Mode
ËFront Headphone JACK (14GT-20 Only)
ËEnglish / Thai OSD
WARNING
Thechassis in thisreceiver ispartially hot. Use anisolation transformerbetween the linecord plugand power
receptacle,whenservicingthischassis. Topreventelectricshock,donotremovecover. Nouser–serviceable
parts inside. Refer servicing to qualified service personnel.
»SPECIFICATIONS ...........................................2
»IMPORTANT SERVICE NOTES ..................... 3
»ADJUSTMENT PRECAUTIONS..................... 4
»TROUBLE SHOOTING TABLE..................... 27
»SOLID STATE DEVICE BASE DIAGRAM .... 31
»CHASSIS LAYOUT ........................................32
»WAVEFORMS................................................34
»DESCRIPTION OF SCHEMATIC DIAGRAM . 35
»SCHEMATIC DIAGRAM
■INFRARED REMOTE CONTROL UNIT .. 36
■TUNER .....................................................37
■14GT15, 14GT20 HOTEL MODE
APPLICATION ..........................................38
■HEAD PHONE Unit and
CRT Socket Unit ...................................... 39
■MAIN Unit .................................................40
»BLOCK DIAGRAM.........................................44
»PRINTED WIRING BOARD ASSEMBLIES .. 49
»REPLACEMENT PARTS LIST
■ELECTRICAL PARTS .............................. 54
■MISCELLANEOUS PARTS...................... 58
■SUPPLIED ACCESSORIES .................... 58
■PACKING PARTS .................................... 58
■CABINET PARTS .................................... 59
Page Page
CONTENTS
COLOUR TELEVISION
Chassis No. UA-1
(14GT15) (14GT20)
S30Y114GT15//

2
14GT15
14GT20
SPECIFICATIONS
Convergence................................................................. Self Convergence System
Focus ............................................................Electrostatic Focus High Bi-Potential
Sweep Deflection ..................................................................................... Magnetic
Intermediate Frequencies
Picture IF Carrier.................................................................................. 38.9MHz
Sound IF Carrier Frequency
5.5MHz...............................................................................................33.4MHz
Colour Sub-Carrier Frequency ........................................................... 34.47MHz
Power Input..................................................................... 100 ~ 240V AC 50/60 Hz
Power Consumption........................................................................................ 65W
Audio Power Output Rating.............................................................. 3.0W(at Max.)
Speaker
Size...................................................................................5 x 9 cm Elliptic (1pc)
Voice Coil Impedance ...........................................................16 ohms at 400 Hz
Aerial Input Impedance
VHF/UHF ..........................................................................75 ohms Unbalanced
Receiving Channel
PAL B/G
VHF-Channels ...................................... E2(48.25MHz) thru E12(224.25MHz)
UHF-Channels .................................. E21(471.25MHz) thru E69(855.25MHz)
Dimensions ...................................................................................Width: 351.0mm
Height: 361.0mm
Depth: 359.0mm
Weight(approx): 9.2 kg
Cabinet material.................................................................................... All Plastics
Specifications are subject to change without prior notice.

3
14GT15
14GT20
IMPORTANT SERVICE NOTES
Maintenance and repair of this receiver should be done by qualified
service personnel only.
SERVICE OF HIGH VOLTAGE SYSTEM AND PIC-
TURE 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 followin
precautions should be observed:
1. When repairing the circuit, be sure not to increase the high voltage to more than 25.8kV
(at beam 0 µA) for the set.
2. To keep the set in a normal opeartion , be sure to make it function on 22.8kV ±1.5kV (at
beam 800 µA) in the case of the set. The set has been factory - Adjusted to the above-
mentioned high voltage.
∴If there is a possibility that the high voltage fluctuates as a result of the repairs,
never forget to check for such high voltage after the work.
3. Do not substitute a picture tube with unauthorizerd types and/or brands which may
cause excess X-ray radiation.
BEFORE RETURNING THE RECEIVER
Before returning the receiver to the user, perform the following safety Checks.
1. Inspect all lead dress to make certain that leads are not pinched or that hardware is not
lodged between the chassis and other metal parts in the receiver.
2. Inspect all protective devices such as non-metallic control knobs, insulating fishpapers,
cabinet backs, adjustment and compartment covers or shields, isolation resistor- ca-
pacity networks, mechanical insulators etc.

4
14GT15
14GT20
ADJUSTMENT PRECAUTIONS
This model's setting are adjusted in two different ways: through the I2C bus control and in the conventional
analog manner. The adjustments via the I2C bus control include preset-only items and variable data.
1. Setting the service mode by the microprocessor.
1. Short JA 122 & JA 124 for 1 second and release to switch to the service mode position, and the
microprocessor is in input mode. (Adjustment through the I2C bus control). (Use JWS Key to set as
well).
2. Press the CH DOWN / UP key on the remote controller to get ready to select the mode one by one.
3. Press the CH DOWN / UP key on the remote controller to select the modes reversibly one by one.
4. Using the VOLUME UP/ DOWN key on the remote controller, the data can be modified.
5. Short JA 122 & JA 124 for 1 second and release to switch to the normal mode (OFF) position, and the
microprocessor is in out of the service mode.
2. Factory Presetting.
1. Short JA 122 & JA 124 for 1 second and release to switch to the service mode position and turn on the
main power switch.Initial values are automatically preset, only when a new EEPROM is used (Judge
with the first 4 bytes ).
2. The initial data are preset as listed in page 7, 8, & 9.
3. Make 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 short JA122 & JA124 to 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
(UA1 Series type RH-iX3368CE Attachment)

5
14GT15
14GT20
SERVICE MODE
(1) In the Service Mode, Key is used to select the mode in the following order.
AGC &
GEOMETRIC
MODE
↓
AGC TAKE OVER POINT (AGC)
↓
VERTICAL SLOPE (V-LIN)
↓
VERTICALAMP (V-AMP)
↓
VERTICAL SHIFT (V-CENT)
↓
HORIZONTAL SHIFT (H-CENT)
↓
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.P. (DRI-BS)
↓
W.P. RED COOL W.P.(DRI-RC)
↓
W.P. GREEN COOL W.P.(DRI-GC)
↓
W.P. BLUE COOL W.P. (DRI-BC)
↓
W.P. RED WARM W.P.(DRI-RW)
↓
W.P. GREEN WARM W.P.(DRI-GW)
↓
W.P. BLUE WARM W.P.(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 GRB 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

6
14GT15
14GT20
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 EXTAV SOURCE (AV)
↓
FM WINDOW SEVECTION (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 CPT (CPT)
↓
B
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)

7
14GT15
14GT20
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 TINT SUB TINT
SHARPNESS UP SUB-SHP
CHANNEL 1 DRI-GS
CHANNEL 4 DRI-BS
CHANNEL 7 CUT-R
CHANNEL FLASH BACK CUT-G
USER DATA IN SERVICE MODE
The flow of Mode lists as following,
* Direct Key-in Step1 Mode

8
14GT15
14GT20
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
S-CORRECTION S-COR 0~63 0 FIX
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 WARM WHITE TEMP DRI-RW 0~63 32 FIX
WHITE POINT GREEN WARM WHITE TEMP DRI-GW 0~63 32 FIX (DRI-GS)-7 DATA
WHITE POINT BLUE WARM WHITE TEMP DRI-BW 0~63 32 FIX (DRI-BS)-7 DATA
WHITE POINT RED COOL WHITE TEMP DRI-RC 0~63 25 FIX
WHITE POINT GREEN COOL WHITE TEMP DRI-GC 0~63 32 FIX (DRI-GS)-7 DATA
WHITE POINT BLUE COOL WHITE TEMP DRI-BC 0~63 32 FIX (DRI-BS)SAME 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
SUB BRIGHTNESS SUB-BRI 0~63 32 ADJ
SUB TINT SUB-TINT 0~63 32 ADJ
SUB SHARPNESS SUB-SHP 0~63 32 ADJ
MAX HOTEL VOLUME HTL-VOL 0~63 32 ADJ
HOTEL PROGRAM NUMBER HTL-PRG 0~99 OR>99FOR NONE 255 FIX
OSD GRB REFERENCE RGB 0~15 15 FIX
BLACK LEVEL OFF-SET R CUT-R 0~15 8 FIX
BLACK LEVEL OFF-SET G CUT-G 0~15 8 FIX
CATHODE DRIVE LEVEL CDL 0~15 0 FIX
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
SHARPNESS OFFSET (NTSC358) SHP-O3 0~15 12 FIX
SHARPNESS OFFSET (NTSC443) SHP-O4 0~15 8 FIX
AFTER SHORT JA 122 & JA 124 ,AND TURN ON THE MAIN POWER SWITCH,READ DATA FROM EEPROM
ADDRESS 00H ~ 03H,AND COMPARE TO THE LIST BELOW, IF DIFFERENT, INITIALIZE THE EEPROM.
Address : Data Address : Data
00H : 55H 02H : 43H
01H : 4FH 03H : A1H

9
14GT15
14GT20
EEPROM ITEMS OSD DATA LENGTH INITIAL DATA FIX/ADJ REMARK
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 ONLY BLK
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 FIX *1
SOUND SYSTEM I S-I 0(DISABLE)/1(ENABLE) 1 FIX *1
SOUND SYSTEM BG S-BG 0(DISABLE)/1(ENABLE) 1 FIX
PLAYBACK SECAM P-SECAM 0(DISABLE)/1(ENABLE) 1 FIX *1
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 FIX *1
FE (RF) SECAM F-SECAM 0(DISABLE)/1(ENABLE) 1 FIX *1
VIDEO MUTE AT IDENT LOSS VMI 0(DISABLE)/1(ENABLE) 1 FIX
VIDEO MUTEAT 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 FIX *2
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 FIX *3
ARABIC LANGUAGE ARA 0(DISABLE)/1(ENABLE) 1 FIX *4
MALAY LANGUAGE MAL 0(DISABLE)/1(ENABLE) 1 FIX *4
CHINESE LANGUAGE CHI 0(DISABLE)/1(ENABLE) 1 FIX *4
FRENCH LANGUAGE FRE 0(DISABLE)/1(ENABLE) 1 FIX *4
RUSSIAN LANGUAGE RUS 0(DISABLE)/1(ENABLE) 1 FIX *4
FORCED V-SYNC SLICING LEVEL FSL 0(DISABLE)/1(ENABLE) 0 FIX
SYNC OF OSD HP2 0(DISABLE)/1(ENABLE) 0 FIX
TUNER CPT CPT 0(BRAZIL)/1(ARGENTINA) 0 FIX
BILINGUAL BIL 0(DISABLE)/1(ENABLE) 0 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
NOTE :
FIXED DATA,PLEASE DO NOT CHANGE WITHOUT SPECIFIC INSTRUCTION.
*1: MANUALLY CHANGE TO 0.
*2: FOR 14GT15, MANUALLY CHANGE TO 0.
*3: MANUALLY CHANGE TO 1.
*4: MANUALLY CHANGE TO 0.

10
14GT15
14GT20
SHIPPING SETTING & CHECKING
(1) The following default data has been factory-set for the E2PROM.
ITEMS DATA SETTING
LAST PROGRAM/CHANNEL 1
FLASHBACK PROGARM/CH 1
DIGIT 1
C-SYSTEM AUTO
S-SYSTEM B/G
SKIP OFF
AFC ON
VOLUME 1
CONTRAST 60 (MAX)
COLOUR 0 (CENTER)
BRIGHTNESS 0 (CENTER)
TINT 0 (CENTER)
SHARPNESS 0 (CENTER)
WHITE TEMP STANDARD
REMINDER TIMER In-active, "--:--"
ON TIMER In-active, "--:--"
OFF TIMER In-active, "--:--"
LAST POWER POWER-ON
LANGUAGE ENGLISH
BLUE BACK MUTE OFF
HOTEL MODE OFF
0 CHANNEL SKIP ON
AFTER PRESSING MODEL SETTING, 0 CHANNEL WILL BE SKIPPED.

11
14GT15
14GT20
PIF ADJUSTMENT
No. Adjusting point Adjusting procedure/conditions Waveform and others
Tuner IFT
( PRESET )
11. Get the tuner ready to receive the CH. E - 9
signal,but with no signal input.
Adjust the PLL data.
2. Connect the sweep generator's output cable to
the tuner antenna. ( RF SWEEP )
3. Adjust the sweep generator's to 80dBuV.
4. Connect the response lead ( use LOW IMPED-
ANCE probe with wave detector ; see Fig.1 ) to
the tuner's IF output terminal. ( This terminal
must have the probe alone connected ).
5. Set the RFAGC to 0 - 6 V with no saturation with
the waveform.
6. Adjust the tuner IF coil to obtain the waveform as
shown in Fig. 2.
Note:Be sure to keep the tuner cover in position
during this adjustment.
RF-AGC
TAKE OVER
POINT AD-
JUSTMENT
(I2C BUS
CONTROL)
1. Receive "PAL COLOUR BAR" signal.
»Signal Strength: 57 ±1 dBµV (75 ohm open)
2. ConnecttheoscilloscopetoTP201(Tuner’sAGC
Terminal) as shown in Fig. 3.
3. Call "AGC" mode in service mode. Adjust the
"AGC" bus data to obtain the Tuner output pin
drop 0.1V below maximum voltage.
4. Change the antenna input signal to 63~67dBµV,
and make sure there is no noise.
5. Turnup the input signal to 90~95 dBµV to be sure
that there is no cross modulation beat.
Note: For the 50 ohm signal
strength gauge, when not
using 50/75 impedance
adapter, signal strength is
52±1dBµV(75 ohm open), in-
stead of 57±1dBµV (75 ohm
open).
Precaution: The loss of using
impedance adapter
2
»Bias box: About 4.5 V
Oscilloscope
0.1V
TV Set
Bias box
TP201+
+
–
–
Fig. 3
E-9 CH
P C
10k
100k
1n60
75ohm
IF OUT
-1.5+/-0.8dB
1000p
Oscilloscope
Fig.1
Fig.2

12
14GT15
14GT20
PURITY ADJUSTMENT
No. Adjusting point Adjusting procedure/conditions Waveform and others
PURITY ADJ. 1. Receive the GREEN-ONLY signal. Adjust the
beam current to about 500 µA.
2. Maintain the purity magnet at the zero magnetic
field and keep the static convergence roughly
adjusted.
3. Observe the points a, b as shown in Fig. 4-1
through the microscope.Adjust the landing to the
A rank requirements.
4. Orient the raster rotation to 0 eastward.
5. Tighten up the deflection coil screws.
»Tightening torque: 108 ±20 N (11 ±2 kgf)
6. Make sure the CRT corners landing meet the A
rank requirements. If not, stick the magnet sheet
to correct it.
Note: This adjustment must be done after
warming up the unit for 30 minutes or
longer with a beam current over 500 µA.
1
ab
A
B
A
B
A = B
A = B
Rank "A"
(on the right of the CRT)
Rank "A"
(on the left of the CRT)
Fig. 4-1
Fig. 4-2
Fig. 4-3

13
14GT15
14GT20
CONVERGENCE ADJUSTMENT
No. Adjusting point Adjusting procedure/conditions Waveform and others
CONVERGENC
ADJ.
( To be done
after the purity
adjustment.
1. Receive the "Crosshatch Pattern" signal.
2. Using the remote controller, call NORMALmode.
STATIC CONVERGENCE
1. Turn the 4-pole magnet to a proper opening an-
gle in order to superpose the blue and red col-
ours.
2. Turn the 6-pole magnet to a proper opening an-
gle in order to superpose the green colour over
the blue and red colours.
DYNAMIC CONVERGENCE
1. Adjust the convergence on the fringes of the
screen in the following steps.
a) Fig.5-1:Drivethe wedgeatpoint"a" andswing
the deflection coil upward.
b) Fig. 5-2: Drive the wedge at points "b" and "c"
and swing the deflection coil downward.
c) Fig.5-3:Drive the "c" wedge deeper and swing
the deflection coil rightward.
d) Fig.5-4:Drivethe"b" wedgedeeper and swing
the deflection coil leftward.
2. Fix all the wedges on the CRT and apply glass
tape over them.
3. Apply lacquer to the deflection yoke lock screw,
magnet unit (purity, 4-pole, 6-pole magnets) and
magnet unit lock screw.
Finally received the Red-only and Blue-only sig-
nalstomakesure there is no other colours on the
screen.
1
RGB
BGR
R
G
B
R
G
B
B
G
R
B
G
R
RGB
BGR
Lacquer
Wedge "a"
Wedge
"b" Wedge
"c"
About
100°
About
100°
4-pole magnet
6-pole magnet
CRT neck
40cm
Lacquer
Purity magnet
Fig. 5-1
Fig. 5-2
Fig. 5-3
Fig. 5-4

14
14GT15
14GT20
CUT-OFF, BACKGROUND AND SUB-CONTRAST ADJUSTMENT
No. Adjusting point Adjusting procedure/conditions Waveform and others
CRT CUTOFF
ADJUSTMENT
(I2C BUS
CONTROL)
1. SwitchTV toVIDEOmode,BLUE BACK OFF, with
NO VIDEO signal.
2. Press R/C to set Picture Normal condition.
3. Connect the oscilloscope to Red OUT from
IC801.(TP851)
Range : 1 V/Div (DC)
Sweep : 5 msec/Div
4. AdjustSCREENVR ,so that thetipofsignal reach
3.0 Vdc + 0.1 Vdc.
1
1 V
3.0Vdc
0
SUB-BRIGHT-
NESS
ADJUSMENT
(I2C BUS
CONTROL)
1. Call"SUB-BRI"in service mode. (ReceiveCross-
hatch pattern with 5 black level windows)
2. Adjust the " SUB BRIGHT " bus data in order that
the line 1, 2 and 3 have the same darkness
whereas line 4 is slightly brighter than line 1, 2
and 3 and finally line 5 will be the brighter than
line 4.
2
1, 2, 3 are in same black level.
1 2 3 4 5
WHITE BAL-
ANCE SERV-
ICE MODE
ADJ. (I2C BUS
CONTROL)
1. Receive the "WHITE" pattern with BURST signal.
2. Press R/C to set Picture NORMAL condition.
3. Connect the DC miliammeter between TP602 (-)
and TP603 (+).
4. Check Beam current should be around 800 µA.
5. Set it to service mode and adjust the " WPG"
(WhitePoint-G), "WPB" (White Point-B) data to
have a colour temperature of 12,300°K ( white ).
* Note .
6. Receive"WHITE"pattern,withBURST signal,and
set Brightness Y by generator, to **10cd/m2
Minolta CA-100) by reducing Luminate Y signal.
7. Adjust"CUT-R"&"CUT-G"to get 12,300°K.Then
go back normal mode. (High Bright)** to check
colour temperature. If out of range, back to 1.
Note: This adjustment must be done after
warming up the unit for 30 minutes or
longer with a beam current over 500µA).
* Adjust DRI-GC/GW, DRI-BC/BW as following
data, after finishing DRI-GS and DRI-BS: DRI-
GC=DRI-GW="DRI-GS"-7:DRI-BW="DRI-BS"-
7:DRI-RC=25:DRI-BC=DRI-BS:DRI-RW=32
** Low=10cd/m2:High=200cd/m2
3* 12300°K X: 0.272
Y: 0.275
(MINOLTA COLOUR ANALYZER
CA-100)
*Note: Above Data can be UP/
DOWN by Volume key.
Maximum
beam check 1. Receive the "Monoscope Pattern" signal. 2. Press R/C to set Picture NORMAL condition.
3. Connect the DC miliammeter between TP603 (+)
and TP602 (–).
(Full Scale: 3 mA Range)
4. Beam current must be within 800 ±100 µA.
4

15
14GT15
14GT20
HORIZONTAL AND VERTICAL DEFLECTION LOOP ADJUSTMENT
No. Adjusting point Adjusting procedure/conditions Waveform and others
V-SLOPE (I2C
BUS CON-
TROL)
V-SHIFT 50
(I2C BUS
CONTROL)
V - AMP 50 (I2C
BUS CON-
TROL)
S-CORREC-
TION (I2C BUS
CONTROL)
H - SHIFT (50)
(H-CENTER)
(I2C BUS
CONTROL)
SUB-SHARP-
NESS
1. Receive Monoscope Pattern Signal.
2. Call the "V-LIN" mode.
3. Increase or decrease "V-LIN" by Volume key till
the horizontal line in the center of monoscope is
just at the position where the blanking starts.
1. Call the "V-CENT" mode.
2. Increase or decrease "V-CENT" by Volume key
till the picture is centered.
1. Call the "V-AMP" mode.
2. Increase or decrease "V - AMP" by Volume key
to set overscan of 9.5% typical.
Adjustment Spec 9.5% range +1% -0%.
FIXED DATA, NO NEED TO ADJUST.
1. Call the "H-CENT" mode.
2. Increase or decrease "H-CENT" by Volume key
to center the picture horizontal.
1. Call the "SUB-SHP" mode.
2. Set "SUB-SHP" to 20 by pressing volume down
button.
1
2
3
4
5
PAL CHROMA ADJUSTMENT
No. Adjusting point Adjusting procedure/conditions Waveform and others
SUB COLOUR
(I2C BUS
CONTROL)
1. Receive the "PAL Colour Bar" signal.
2. Press R/C to set Picture Normal condition.
3. Connecttheoscilloscope to Redcathode(TP854).
»Range : 20 V/div. (AC) (Using 10:1 probe)
»Sweep time : 10 µsec/div.
4. UsingtheR/Ccall "SUB COL"inSERVICE mode.
Adjust SUB COLOUR bus data, so that the 75%
White & Red portions of PALColour Bar be at the
same level shown as Fig. 8.
5. Clear the SERVICE mode.
1
Cy GB
WY 100%W
75% Mg R
Fig. 8
6
Focus 1. Receive the "Monoscope Pattern" signal.
2. Press R/C to set Picture NORMAL condition.
3. Adjust the focus control to get the best focus.
7

16
14GT15
14GT20
No. Adjusting point Adjusting procedure/conditions Waveform and others
SUB-TINT (I2C
BUS CON-
TROL)
1. Receive the "NTSC3.58 Colour Bar" signal
throughAV in.
2. Connect the oscilloscope to TP853 (Pin (5) of
P882) BLUE-OUT.
»Range :100mV/div. (AC)(UseProbe10:1)
»Sweep time : 10 µsec/div.
3. Call the "SUB-TINT" mode in service mode. Ad-
just the "SUB-TINT" bus data to obtain the wave-
form shown as Fig. 9.
4. Clear the SERVICE mode.
1
Fig. 9
NTSC CHROMA ADJUSTMENT
No. Adjusting point Adjusting procedure/conditions Waveform and others
BEAM PRO-
TECTOR 1. Receive "Monoscope Pattern" signal. 2. Set CONTRAST MAX.
3. Set BRIGHT MAX.
4. During the Collector & Emitter of Q883/5/7 short,
makesurethe protectorON andswitchtostandby
mode.
1* Select one of Q883/5/7 to do
each short test.
H, V PROTEC-
TOR 1. Receive "Monoscope Pattern" signal. 2. Connect output of Bias Box to D607 cathode
(R606 side).
3. Set voltage of Bias Box to 18V and make sure
the protector is not work.
4. Set voltage of Bias Box to 27V, and make sure
the protector is work.
2
Other
protectors 1. Once finish rectified Electrolytic Capacitor short testing in +B line, check all possible damaged
components on +B line.
(Use random selected set for inspection)
3
PROTECTOR OPERATION CHECKING
No. Adjusting point Adjusting procedure/conditions Waveform and others
VIDEO AND
AUDIO
OUTPUT
CHECK
1. Receive the "PALColor Bar" signal (100% White
Color Bar, Sound 400 Hz 100% Mod.)
2. Terminate the Video output with a 75 ohm imped-
ance. Make sure the output is as specified (1.0
Vp-p ±3 dB).
3. Terminate the Audio output with a 10k ohm im-
pedance. Make sure the output is as specified
(1.76 Vp-p ±3 dB).
1
VIDEO AND
AUDIO INPUT
CHECK
1. Using the TV/AV key on the remote controller,
make sure that the modes change in order of TV,
AV1,AV2 & TV again and the video & audio out-
put are according to the input terminal for each
mode.
2
A/V INPUT AND OUTPUT CHECKING
WYCy G Mg R B
(SAME LEVEL)

17
14GT15
14GT20
FUNCTION OPERATION CHECKING (VIDEO AND AUDIO)
No. Adjusting point Adjusting procedure/conditions Waveform and others
CONTRAST
key 1. Receive "Monoscope Pattern" signal. 2. Set P-Mode to select CONTRAST.
3. PressVolumeUp/Downkeytocheckwhetherthe
CONTRAST effect is OK or not.
1
1. Receive "Color Bar" signal.
2. Set P-Mode to select COLOUR.
3. Press Volume Up/Down key to check whether
the COLOUR effect is OK or not.
2COLOUR key
BRIGHTNESS
key 1. Receive "Monoscope Pattern" signal. 2. Set P-Mode to select BRIGHTNESS.
3. Press Volume Up/Down key to check whether
the BRIGHTNESS effect is OK or not.
3
TINT key 1. Receive the "NTSC Colour Bar" signal thruAV in.
2. Set P-Mode to select TINT.
3. Press Volume Up/Down key to check TINT, UP
for GREEN direction and DOWN for PURPLE di-
rection whether is OK or not.
4
SHARPNESS
Key 1. Receive "Monoscope Pattern" signal. 2. Set P-mode to select SHARPNESS.
3. Press Volume Up/Down key to check whether
the SHARPNESS effect is OK or not.
5
WHITE TEMP 1. Receive "Monoscope Pattern" signal.
2. Set FUNCTION to select WHITE TEMP.
3. Press Volume Up/Down key to check WHITE
TEMP Option, STANDARD:
NORMAL SETTING, WARM for more REDDISH
direction changing, COOL for more BLUISH di-
rection changing.
8
NORMAL Key71. Once in PICTURE Mode, and the NORMAL key
is pressed, all the settings will be present to nor-
mal setting.
(Normal setting value for every mode).
»CONTRAST : MAX
»COLOUR : CENTER
»BRIGHTNESS : CENTER
»TINT : CENTER
»SHARPNESS : CENTER
Notes:If nothing is display
mean contrast, colour, bright,
tint, sharpness are all in nor-
mal setting.
CH DISPLAY
COLOUR 1. All Ch (1~99) will have an OSD display of the channel number in green colour under AFT ON
condition.
6

18
14GT15
14GT20
FUNCTION OPERATION CHECKING (VIDEO AND AUDIO)
(Continued)
No. Adjusting point Adjusting procedure/conditions Waveform and others
COLOUR
SYSTEM 1. Receive the "PAL COLOUR BAR" signal, press the COLOUR SYSTEM key to select modes ex-
ceptPAL,checkthe COLOURisnot workingprop-
erly. Then, select the "PAL" mode. Check again
its colour so that it is working properly.
2. Receive "NTSC 4.43/3.58 COLOUR BAR" signal
throughAV, press COLOUR SYSTEM key to se-
lect modes except N4.43/3.58, check the COL-
OUR is not working properly. Then, select the
"NTSC 4.43/3.58" mode. Check again its colour
so that it is working properly.
9
SOUND
SYSTEM
10 1. Receive "PAL-B/G" signal, and check the sound
output is working properly or not.
1. Receive "PAL COLOUR BAR" signal.
2. Turn up the volume control to maximum, make
sure the sound is heard from the speakers. Then
put the unit in no signal state.
3. Check the sound mute is effective.
4. Finally turn sound level of CTV to minimum.
NOISE MUTE
CHECKING
11
OSD LAN-
GUAGE
QUANTITY
CHECK
Check OSD LANGUAGE quantity and type as be-
low:
ENGLISH, THAI.
12
HEADPHONE JACK CHECKING (FOR B & C MODELS ONLY)
No. Adjusting point Adjusting procedure/conditions Waveform and others
HEADPHONE
OUTPUT
CHECKING
1. ReceivePALCOLOURPAR with SOUND400Hz,
100% MODULATION (±50kHz Dev).
2. Maximum volume, and check the headphone
output with 400Hz sound and no sound out from
speaker.
1

19
14GT15
14GT20
MEMORY MAP
ADDRESS DATA MICON E
2
PROM E
2
PROM CHASSIS CTV FINAL LAST INITIAL
REMARK
(HEX) D7 D6 D5 D4 D3 D2 D1 D0 DEFAULT RANGE WRITE(CPU) CHECK DATA CHECK TYPE CHECK DATA CHECK TYPE SETTING DATA
MODEL MODEL
LETTER NO. LETTER NO.
00 PASS WORD 55 00-FF
01 PASS WORD 4F 00-FF
02 PASS WORD 43 00-FF
03 PASS WORD A1 00-FF
04
05
06 AGC TAKE-OVER 0E 00-3F
07 V-SLOPE 20 00-3F
08 V-AMPLITUDE 20 00-3F
09 V-CENTER 20 00-3F
0A H-CENTER 20 00-3F
0B H-SIZE 20 00-3F
0C EW-PARALLELOGRAM 20 00-3F
0D EW-PARABOLA/WIDTH 20 00-3F
0E EW-UPPER CORNER 20 00-3F
0F EW-LOWER CORNER 20 00-3F
10 EW-TRAPEZIUM 20 00-3F
11 HORIZONTAL-BOW 20 00-3F
12 S-CORRECTION 00 00-3F
13
14
15
16 DRIVER-R (STANDARD) 20 00-3F
17 DRIVER-G (STANDARD) 20 00-3F
18 DRIVER-B (STANDARD) 20 00-3F
19 DRIVER-R (WARM) 20 00-3F
1A DRIVER-G (WARM) 20 00-3F
1B DRIVER-B (WARM) 20 00-3F
1C DRIVER-R (COOL) 19 00-3F
1D DRIVER-G (COOL) 20 00-3F
1E DRIVER-G (COOL) 20 00-3F
1F
20
21
22 SUB-VOLUME 3F 00-3F
23 SUB-CONTRAST 3F 00-3F
24 SUB-COLOUR 20 00-3F
25 SUB-BRIGHTNESS 20 00-3F
26 SUB-TINT 20 00-3F
27 SUB-SHARPNESS 20 00-3F
28 HTL-VOLUME 20 00-3F
29 HTL-POSITION FF 00-3F
2A
2B
2C
2D OSD-ENCEREFER 20 00-3F
2E CUTOFF LEVEL-OFFSET R 08 00-3F
2F CUTOFF LEVEL-OFFSET B 08 00-3F
30 CATHODE DRIVE LEVEL 00 00-3F
31 Y-DELAY (TV PAL) 0C 00-3F
32 Y-DELAY (TV SECAM) 0F 00-3F
33 Y-DELAY (TV N358) 0C 00-3F
34 Y-DELAY (TV N443) 0C 00-3F
35 Y-DALAY (TV BW) 0C 00-3F
36 Y-DELAY (AV PAL) 0C 00-3F
37 Y-DELAY (AV SECAM) 0F 00-3F
38 Y-DELAY (AV N443) 0C 00-3F
39 Y-DELAY (AV N358) 0F 00-3F
3A Y-DELAY (AV BW) 0C 00-3F
3B COLOUR-OFFSET (PAL) 08 00-3F
3C COLOUR-OFFSET (SECAM) 08 00-3F
3D COLOUR-OFFSET (N443) 04 00-3F
3E COLOUR-OFFSET (N358) 04 00-3F
3F SHARPNESS-OFFSET (PAL) 08 00-3F

20
14GT15
14GT20
ADDRESS DATA MICON E
2
PROM E
2
PROM CHASSIS CTV FINAL LAST INITIAL
REMARK
(HEX) D7 D6 D5 D4 D3 D2 D1 D0 DEFAULT RANGE WRITE(CPU) CHECK DATA CHECK TYPE CHECK DATA CHECK TYPE SETTING DATA
MODEL MODEL
LETTER NO. LETTER NO.
40 SHARPNESS-OFFSET (SECAM) 04 00-0F
41 SHARPNESS-OFFSET (N443) 0C 00-0F
42 SHARPNESS-OFFSET (N358) 08 00-0F
43
44 FCO ACL OSO EHT EVG FFI AVL BKS 00-FF
45 SCM N443 N358 PB-SEC BG I DK M 00-FF
46 SM FMWS AV BTSC HTL VMC VMI 00-FF
47 HP2 FSL RUS FRA CHN MLY ARB THA 00-FF
48 AGC BIL OBA 00-FF
49
4A
4B
4C VOLUME 01 00-3C
4D CONTRAST 3C 00-3C
4E COLOUR 1E 00-3C
4F BRIGHTNESS 1E 00-3C
50 TINT 1E 00-3C
51 SHARPNESS 1E 00-3C
52
53
54
55 POSITION/AV1/AV2 01 00-FF
56 FAV-POS A 0A 00-FF
57 FAV-POS B 14 00-FF
58 FAV-POS C 1E 00-FF
59 FAV-POS D 28 00-FF
5A
5B
5C POWER 00 00-01
5D WHITE-TEMP 00 00-02
5E BLUE BACK 00 00-01
5F LANGUAGE 00 00-07
60 DIGIT 00 00-01
61
62 SKIP 0 SKIP 1 SKIP 2 SKIP 3 SKIP 4 SKIP 5 SKIP 6 SKIP 7 80 00-FF
63 SKIP 8 SKIP 9 SKIP 10 SKIP 11 SKIP 12 SKIP 13 SKIP 14 SKIP 15 00 00-FF
64 SKIP 16 SKIP 17 SKIP 18 SKIP 19 SKIP 20 SKIP 21 SKIP 22 SKIP 23 00 00-FF
65 SKIP 24 SKIP 25 SKIP 26 SKIP 27 SKIP 28 SKIP 29 SKIP 30 SKIP 31 00 00-FF
66 SKIP 32 SKIP 33 SKIP 34 SKIP 35 SKIP 36 SKIP 37 SKIP 38 SKIP 39 00 00-FF
67 SKIP 40 SKIP 41 SKIP 42 SKIP 43 SKIP 44 SKIP 45 SKIP 46 SKIP 47 00 00-FF
68 SKIP 48 SKIP 49 SKIP 50 SKIP 51 SKIP 52 SKIP 53 SKIP 54 SKIP 55 00 00-FF
69 SKIP 56 SKIP 57 SKIP 58 SKIP 59 SKIP 60 SKIP 61 SKIP 62 SKIP 63 00 00-FF
6A SKIP 64 SKIP 65 SKIP 66 SKIP 67 SKIP 68 SKIP 69 SKIP 70 SKIP 71 00 00-FF
6B SKIP 72 SKIP 73 SKIP 74 SKIP 75 SKIP 76 SKIP 77 SKIP 78 SKIP 79 00 00-FF
6C SKIP 80 SKIP 81 SKIP 82 SKIP 83 SKIP 84 SKIP 85 SKIP 86 SKIP 87 00 00-FF
6D SKIP 88 SKIP 89 SKIP 90 SKIP 91 SKIP 92 SKIP 93 SKIP 94 SKIP 95 00 00-FF
6E SKIP 96 SKIP 97 SKIP 98 SKIP 99 00 00-FF
6F
70
71
72
73
74 TUNING FREQUENCY (HIGHER PART) S-SYS POS 0
75 TUNING FREQUENCY (LOWER PART) 000:BG
76 S-SYS AFT (auto) C-SYS 001:I
77 TUNING FREQUENCY (HIGHER PART) 010:DK POS 1
78 TUNING FREQUENCY (LOWER PART) 011:M
79 S-SYS AFT (auto) C-SYS
7A TUNING FREQUENCY (HIGHER PART) AFT POS 2
7B TUNING FREQUENCY (LOWER PART) 0:OFF
7C S-SYS AFT (auto) C-SYS 1:ON
7D TUNING FREQUENCY (HIGHER PART) POS 3
7E TUNING FREQUENCY (LOWER PART)
7F S-SYS AFT (auto) C-SYS