SHARP 27J-S100, 27J-S180, 27J-S260, CJ27S10, CJ27S26 Diagram

27J-S100/180/260 CJ27S10/26
SERVICE MANUAL
S37W727J-S100
COLOR TELEVISION
Chassis No. SN-71
27J-S180
27J-S100/S260
CJ27S10/26
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.
» ELECTRICAL SPECIFICATIONS ............................................................................................. 1
» IMPORTANT SERVICE SAFETY PRECAUTION ..................................................................... 2
» LOCATION OF USER'S CONTROL.......................................................................................... 6
» INSTALLATION AND SERVICE INSTRUCTIONS .................................................................... 9
» CHASSIS LAYOUT .................................................................................................................16
» BLOCK DIAGRAM ..................................................................................................................18
» PRINTED WIRING BOARD ASSEMBLIES.............................................................................20
» SCHEMATIC DIAGRAMS....................................................................................................... 26
» REPLACEMENT PARTS LIST................................................................................................ 42
» PACKING OF THE SET .......................................................................................................... 60
27J-S100/180/260 CJ27S10/26
CONTENTS
Page
ELECTRICAL SPECIFICATIONS
POWER INPUT............................................... 120 V AC 60 Hz
POWER RATING ............................................................ 126 W
PICTURE SIZE ...................................... 2,193cm2(340sq inch)
CONVERGENCE ........................................................ Magnetic
SWEEP DEFLECTION ............................................... Magnetic
FOCUS .......................................... Hi-Bi-Potential Electrostatic
INTERMEDIATE FREQUENCIES
Picture IF Carrier Frequency................................ 45.75 MHz
Sound IF Carrier Frequency................................. 41.25 MHz
Color Sub-Carrier Frequency ............................... 42.17 MHz
.............................................................................. (Nominal)
AUDIO POWER .........................................................................
OUTPUT RATING ........................... 2.6W (at 10% distortion)
SHARP ELECTRONICS CORPORATION
Service Headquarters: Sharp Plaza, Mahwah, New Jersey 07430-2135
SHARP ELECTRONICS OF CANADA LTD.
335 Britannia Road East Mississauga,Ontario L4Z 1W9 Canada
SPEAKER
SIZE ................................................................... 8cm(Round)
VOICE COIL IMPEDANCE .......................... 8ohm at 400 Hz
ANTENNA INPUT IMPEDANCE
VHF/UHF................................................75 ohm Unbalanced
TUNING RANGES
VHF-Channels........................................................... 2thru 13
UHF-Channels ........................................................ 14thru 69
CATV Channels.......................................................1thru 125
............................................................... (EIA, Channel Plan)
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27J-S100/180/260 CJ27S10/26
5
Service work should be performed only by qualified service technicians who are thoroughly familiar with all safety checks and servicing guidelines which follow:
IMPORTANT SERVICE SAFETY PRECAUTION
WARNING
1. For continued safety, no modification of any circuit should be attempted.
2. Disconnect AC power before servicing.
3. Semiconductor heat sinks are potential shock hazards when the chassis is operating.
4. The chassis in this receiver has two ground systems which are separated by insulation material. The non­isolated (hot) ground system is for the B+ voltage regulator circuit and the horizontal output circuit.The isolated ground system is for the low B+ DC voltages and the secondary circuit of the high voltage transformer. To prevent electrical shock use an isolation transformer between the line cord and power receptacle, when servicing this chassis.
CAUTION: FOR CONTINUED PROTECTION AGAINST A RISKOF FIRE, REPLACE ONLY
4A 125V
WITH SAME TYPE 4A-125V FUSE.
SERVICING OF HIGH VOLTAGE SYSTEM AND PICTURE TUBE
When servicing the high voltage system, re­move the static charge by connecting a 10k ohm resistor in series with an insulated wire (such as a test probe) between the picture tube ground and the 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 anode completely.
X-RADIATION AND HIGH VOLTAGE LIMITS
1. Be sure all service personnel are aware of the procedures and instructions covering X-radiation. The only potential source of X-ray in current solid state TV receivers is the picture tube. However, the picture tube does not emit measurable X-Ray radiation if the high voltage is as specified in the "High Voltage Check" instructions. It is only when high voltage is excessive that X­radiation is capable of penetrating the shell of the picture tube including the lead in glass material. The important precaution is to keep the high voltage below the maximum level specified.
2. It is essential that service personal have available at all times an accurate high voltage meter. The calibration of this meter should be checked periodically.
3. High voltage should always be kept at the rated value
- no higher. Operation at higher voltages may cause a failure of the picture tube or high voltage circuitry and;also under certain conditions, may produce radiation exceeds specifications.
4. When the high voltage regulator is operating properly there is no possibility of an X-radiation problem. Every time a color chassis is serviced, the brightness should be tested while monitoring the high voltage with a meter to be certain that the high voltage does not exceed the specified value and that it is regulating correctly.
5. Do not use a picture tube other than that specified or make unrecommended circuit modifications to the high voltage circuitry.
6. When trouble shooting and taking test measurements on a receiver with excessive high voltage, avoid being unnecessarily close to the receiver. Do not operate the receiver longer than is necessary to locate the cause of excessive voltage.
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IMPORTANT SERVICE SAFETY PRECAUTION
BEFORE RETURNING THE RECEIVER
(Fire & Shock Hazard)
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 materials, cabinet backs, adjustment and compartment covers or shields, isolation resistor-capacity networks, mechanical insulators, etc.
3. To be sure that no shock hazard exists, check for leakage current in the following manner.
» Plug the AC cord directly into a 120 volt AC outlet,
(Do not use an isolation transformer for this test).
» Using to clip leads, connect a 1.5k ohm, 10 watt
resistor paralleled by a 0.15µF capacitor in series with all exposed metal cabinet parts and a known earth ground, such as electrical conduit or electrical ground connected to earth ground.
» Use an AC voltmeter having with 5000 ohm per volt,
or higher, sensitivity to measure the AC voltage drop across the resistor.
» Connect the resistor connection to all exposed metal
parts having a return to the chassis (antenna, metal cabinet, screw heads, knobs and control shafts, escutcheon, etc.) and measure the AC voltage drop across the resistor. AII check must be repeated with the AC line cord plug connection reversed. (IF necessary, a non-polarized adapter plug must be used only for the purpose of completing these check.) Any current measured must not exceed 0.5 milliamp. Any measurements not within the limits outlined above are indicative of a potential shock hazard and corrective action must be taken before returning the instrument to the customer.
27J-S100/180/260 CJ27S10/26
(Continued)
SAFETY NOTICE
Many electrical and mechanical parts in television receivers have special safety-related characteristics. These characteristics are often not evident from visual inspection, nor can protection afforded by them be necessarily increased by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have specialsafety characteristics are identified in this manual; electrical components having such features are identified by " å " and shaded areas in the
Schematic Diagrams
replacement parts must be identical to those used in the original circuit. The use of substitute replacement parts which do not have the same safety characteristics as the factory recommended replacement parts shown in this service manual, may create shock, fire, X-radiation or other hazards.
Replacement Parts Lists
. For continued protection,
and
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27J-S100/180/260 CJ27S10/26
PRECAUTIONS A PRENDRE LORS DE LA REPARATION
Ne peut effectuer la réparation qu' un technicien spécialisé qui s'est parfaitement accoutumé à toute vérification de sécurité et aux conseils suivants.
AVERTISSEMENT
1. N'entreprendre aucune modification de tout circuit. C'est dangereux.
2. Débrancher le récepteur avant toute réparation.
3. Les déversoirs thermiques à semi-conducteurs peuvent présenter un danger de choc électrique lorsque le réceqteur est en marche.
4. Le châssis de ce récepteur a deux systèmes de mise à la terre qui sont séparés par un matériau isolant. Le système de mise à la terre non-isolée (chaud) est pour le circuit du régulateur de tension B+ et le circuit de sortie horizontale. Le système de mise à la terre isolé est pour les basses tensions C. C.B + et le circuit secondaire du transformateur de haute tension.
PRECAUTION:POUR LA PROTECTION CONTINUE CONTRE LES RISQUES
4A 125V
D'INCENDIE, REMPLACER LE FUSIBLE PAR UN FUSIBLE DE MEME TYPE 4A-125V .
REPARATION DU SYSTEME A HAUTE TENSION ET DU TUBE-IMAGE
Lors de la réparation de ce systéme, supprimer la charge statique en branchant une résistance de 10 k en série avec un fil isolé (comme une sonde d'essai) entre la mise à la terre du tube-image et le fil d'anodel. (Le corden d'alimentation doit être retiré de la prise murale.)
1. Le tube image dans ce récepteur emploie une protection intégrée contre l'implosion.
2. Par mesure de sécurité, changer le tube-image pour un tube du même numéro de type.
3. Ne pas lever le tube-image par son col.
4. Ne manipuler le tube-image qu'en porant des lunettes incassables et qu'après avoir déchargé totalement la haute tension.
LIMITES DES RADIATIONS X ET DE LA HAUTE TENSION
1. Tout le personnel réparateur doit être instr uit des instructions et procédés relatifs aux radiations X. Le tube-image, seule source de rayons X dons les téleviseurs transistorisés, n'émet pourtant pas de rayons mesurables si la haute tension est maintenue à un niveau préconisé dans la section "Vérification de la haute tension". C'est seulement quand la haute tension est excessive que les rayons X peuvent entrer dans l'enveloppe du tube-image y compris le conducteur de verre. Il est important de maintenir la haute tension en­dessous du niveau spécifié.
2. Il est essentiel que le réparateur ait sous la main un voltmètre à haute tension qui doit être périodiquement étalonné.
3. La haute tension doit toujours être maintenue à la valeur de régime -et pas plus haute. L'opération à des tensions plus élevées peut entraîner une panne du tube-image ou du circuit à haute tension et, dans certaines conditions, peut entraîner une radiation dépassant les niveaux préscrits.
4. Quand le régulateur à haute tension fonctionne correctement, il n'y a aucun problème de radiation X. Chaque fois qu'un châssis couleurs est réparé, la luminosité doit être examinée bout en contrôlant la haute tension à l'aide d'un voltmètre pour s'assurer que la haute tension ne dépasse pas la valeur spécifiée et qu'elle soit correctement réglée.
5. Ne pas utiliser un tube-image autre que celui spécifié et ne pas effectuer de modifications déconseillées du circuit à haute tension.
6. Lors de la recherche des pannes et des mesures d'essai sur un récepteur qui présente une haute tension excessive, éviter de s'approcher inutilement du récepteur. Ne pas faire fonctionner le récepteur plus longtemps que nécessaire pour localiser la cause de la tension excessive.
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27J-S100/180/260
2
2
2
CJ27S10/26
PRECAUTIONS A PRENDRE LORS DE LA REPARATION
(Suite)
VERIFICATIONS CONTRE L'INCEN-DIE ET LE CHOC ELECTRIQUE
Avant de rendre le récepteur à l'utilisateur, effectuer les vérifications suivantes.
1. Inspecter tous les faisceaux de câbles pour s'assurer que les fils ne soient pas pincés ou qu'un outil ne soit pas placé entre le châssis et les autres pièces métalliques du récepteur.
2. Inspecter tous les dispositifs de protection comme les boutons de commande non-métalliques, les isolants, le dos du coffret, les couvercles ou blindages de réglage et de compartiment, les réseaux de résistance-capacité, les isolateurs mécaniques, etc.
3. S'assurer qu'il n'y ait pas de danger d'électrocution en vérifiant la fuite de courant, de la facon suivante:
» Brancher le cordon d'alimentation directem-ent à une
prise de courant de 120V. (Ne pas utiliser de transformateur d'isolation pour cet essai).
» A l'aide de deux fils à pinces, brancher une résistance
de 1.5 k 10 watts en parallèle avec un condensateur de 0,15µF en série avec toutes les pièces métalliques exposées du coffret et une terre connue comme une conduite électrique ou une prise de terre branchée à la terre.
» Utiliser un voltmètre CA d'une sensibilité d'au moins
5000/V pour mesurer la chute de tension en travers de la résistance.
» T oucher av ec la sonde d'essai les pièces métalliques
exposées qui présentent une voie de retour au châssis (antenne, coffret métallique, tête des vis, arbres de commande et des boutons, écusson, etc.) et mesurer la chute de tension CA en-travers de la résistance. Toutes les vér ifications doivent être refaites après avoir inversé la fiche du cordon d'alimentation. (Si nécessaire, une prise d'adpatation non polarisée peut être utilisée dans le but de terminer ces vérifications.) Tous les courants mesurés ne doivent pas dépasser
0.5 mA. Dans le cas contraire, il y a une possibilité de choc électrique qui doit être supprimée avant de rendre le récepteur au client.
V oltmètre CA
1.5k ohm 10w
0.15µF
SONDE D'ESSAI
TEST PROBE
AUX PIECES
TO EXPOSED
METALLIQUES METAL PARTS
EXPOSEES
234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121
BRANCHER A UNE
CONNECT TO KNOWN EARTH
TERRE CONNUE
GROUND
AVIS POUR LA SECURITE
De nombreuses pièces, électriques et mécaniques, dans les téléviseurs présentent des caractéristiques spéciales relatives à la sécurité, qui ne sont souvent pas évidentes à vue. Le degré de protection ne peut pas être nécessairement augmentée en utilisant des pièces de remplacement étalonnées pour haute tension, puissance, etc. Les pièces de remplacement qui présentent ces caractéristiques sont identifiées dans ce manuel; les pièces électriques qui présentent ces particularités sont
234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121
234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121
identifiées par la marque " å " et hachurées dans la liste des pièces de remplacement et les diagrammes schématiques. Pour assurer la protection, ces pièces doivent être identiques à celles utilisées dans le circuit d'origine. L'utilisation de pièces qui n'ont pas les mêmes caractéristiques que les pièces recommandées par l'usine, indiquées dans ce manuel, peut provoquer des électrocutions, incendies, radiations X ou autres accidents.
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27J-S100/180/260 CJ27S10/26
LOCATION OF USER'S CONTROL
(27J-S100/CJ27S10)
- 6 -
LOCATION OF USER'S CONTROL
27J-S260/CJ27S26
27J-S100/180/260 CJ27S10/26
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27J-S100/180/260 CJ27S10/26
27J-S180
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27J-S100/180/260 CJ27S10/26
INSTALLATION AND SERVICE INSTRUCTIONS
Note: (1) When performing any adjustments to resistor controls and transformers use non-metallic
screwdriver or TV alignment tools.
(2 ) Before performing adjustment, TV set must be on at least 15 minutes.
CIRCUIT PROTECTION The receiver is protected by a 4.0A fuse
(F701), mounted on PWB-A, wired into one side of the AC line input.
X-RADIATION PROTECTOR CIRCUIT TEST
After service has been performed on the horizontal deflection system, high voltage system, B+ system, test the X-Radiation protection circuit to ascertain proper operation as follows:
1) Apply 120V AC using a variac transformer for accurate input voltage.
2) Allow for warm up and adjust all customer controls for normal picture and sound.
3) Select a local channel.
4) Connect a digital voltmeter to TP653 and make sure that the voltmeter reads 11.4V.
5) Apply external 13.8V DC at TP653 by using an external DC supply, TV must be shut off.
6) To reset the protector, unplug the ac cord and make a short circuit between TP651 and TP652.Now make sure that normal picture appears on the screen.
7) If the operation of the horizontal oscillator does not stop in step 5, the circuit must be repaired before the set is returned to the customer.
HIGH VOLTA GE CHECK
High voltage is not adjustable but must be checked to verify that the receiver is operating within safe and efficient design limitations as specified checks should be as follows:
1. Connect an accurate high voltage meter between ground and anode of picture tube.
2. Operate receiver for at least 15 minutes at 120V AC line voltage, with strong air signal or properly tuned in test signal.
3. Set service mode on, service No.19 and Bus data "01" (Y-mute on ).
4. The voltage should be approximately 28.3kV(27J­S100/S120,CJ27S10/26),29.3kV(27J-S180) (at zero beam). If a correct reading cannot be obtained, check circuitry for malfunctioning components. After the voltage test, make Y-mute off (normal mode).
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27J-S100/180/260 CJ27S10/26
For adjustments of this model, the bus data is convered to various analog signals by the D-A converter circuit.
Note: There are still a few analog adjustments in this series such as focus and master screen voltage. Follow the steps below whenever service adjustment is required. See Figure "B" to determine if service adjust-
ments are required.
1.Service mode -
Before putting unit into the service mode, check, that customer adjustments are in the normal mode. use the reset function in the video adjust menu to ensure customer controls are in their proper ( reset ) position.
2. Service number selection
Once in the service mode, press the channel up or channel down button on the remote transmitter or at the set. the service adjustment number will vary in increments of one, from S01 to P06(27J-S260/ CJ27S26),S01 to M05 (27J-S100/180/CJ27S10) Select the item you wish to adjust.
3.Data number selection
Press the volume up or down button to adjust the data number .
DATA NUMBER
SERVICE ADJUSTMENT NUMBER
To enter the service mode and exit serv­ice mode.
While pressing the Vol-up and Ch-up buttons at once,plug the AC cord into a wall socket. Now the TV set is switched on and enters the service mode. To exit the service mode shut the television off by pressing the power button.
S01 55
CHANNEL
02
Figure B
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27J-S100/180/260 CJ27S10/26
SERVICE NUMBER
S01 PICTURE 55 00-7F S02 TINT 46 00-7F S03 COLOR 32 00-7F S04 BRIGHTNESS 40 00-7F S05 SHARPNESS 28 00-3F Must be set to "28" S06 VERTICAL PHASE 00 00-07 Must be set to "00" S07 HORIZONTAL PHASE 12 00-1F S08 RF-AGC 2A 00-3F S09 VERTICAL AMP 20 00-3F S10 VCO 2C 00-7F S11 R CUT-OFF 00 00-FF S12 G CUT -OFF 00 00-FF S13 B CUT-OFF 00 00-FF S14 G GAIN 7F 00-FF S15 B GAIN 7F 00-FF S16 TRAP(3.58MHz) 00 00 or 01 Must be set to "00" S17 BALANCE 20 00-3F Must be set to "20" S18 C.C.POSITION 18 00-7F S19 Y-MUTE 00 00,01,03 00=NORMAL 01=noY 03=NO VERTICAL OP OPTION (set to each Model) 49 or 78 00-FF "49"=CJ27S10."78"=27J-S260/
M01 MTS LEVEL 0A 00-0F
ADJUSTMENT ITEM
INITIAL V ALUE
DAT A
ADJUSTMENT CONTENTS
RANGE
CJ27S26,"49"=S100. "79"=S180
M02 STEREO-VCO 20 00-3F
M03 FILTER 1C 00-3F M04 LOW SEPARATION 20 00-3F M05 HIGH SEPARATION 1B 00-3F P01 P in P Y-LEVEL 30 00-7F P02 P in P TINT 1B 00-3F Must be set to "1C". P03 P in P COLOR 29 00-7F P04 P in P Y-OFFSET 10 00-1F Must be set to "16". P05 P in P H-Position 0B 00-FF Must be set to "0B". P06 P in P BURST GATE PULSE 09 00-7F Must be set to "09".
27J-S260
CJ27S26
Table - A
Holding down both the CH UP/DOWN keys on the TV set at service mode for more than 2 seconds will automati­cally write the above initial values into IC2101.
PART REPLACED
IC2001
ADJUSTMENT
NECESSARY
UNNECESSARY
x
Data is stored in IC2101.
NOTES
The adjustment is needed to compensate for
IC201
IC2101
x
x
characteristics of parts including IC201 and MTS level (M01).
Holding down both the CH UP/DOWN keys on the TV set at service mode for more than 2 seconds will automatically write the above initial values into IC2101.Then perform a complete adjustment.
CRT
IC3001 IC1801
(27J-S260
x
x x
Adjust items related to picture tube only. Adjust items related to MTS only (M01~M05).
Adjust items related to P-IN-P only (P01~P06).
/CJ27S26)
Table - B
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27J-S100/180/260 CJ27S10/26
Ë Ë
Ë adjustment
Ë Ë
VCO Adjustment
1. Connect a digital voltmeter between pin 44 of IC201 and ground.
2. Select a good local channel.
3. Enter the service mode. select adjustment "S10".
4. Adjust the data so that digital voltmeter shold read
2.2V
5. Adjustment is complete, remove the volt-meter, return to "normal" mode.
RF AGC Adjustment
White balance adjustment
1. Have unit receive a good local channel.
2. Enter the service mode. select service adjustment "S 03" and set to "00" ( minimum color)(Record original data code under adjustment "S03" before changing) . "S 03" does not have to be adjusted if you selected a B/W picture or monoscope pattern.
3. Alternately adjust service adjustment data of "S14" and "S15" untill a good grey scale with normal whites is obtained.
4. Select service adjustment "S 03"and adjust data to obtain normal color level.
1. Have unit receive a good local channel.
2. Enter the service mode and select service adjustment "S 08".
3. Set the data value to point where no noise or beat appears.
4. Select another channel to confirm that no noise or beat appears.
NOTE1 :You will have to come out of the service
mode to select another channel.
NOTE2 :Setting the data to "0 0" will pro-duce a
black raster.
Screen adjustment
1. Connect a digital voltmeter between TP852 and TP853 on the CRT socket PWB.
Note:These test points may not be provided.
Then connect the voltmeter to both ends of R852 located near Q851 on the foil side.
2. Select a good local channel.
3. Enter the service mode and select service adjustment "S03" and set the data value to "00" to set the color level to minimum.(Record original data code under adjustment "S03" before changing) You may skip this step if you selected a B/W picture or monoscope pattern.
4. Select service adjustment "S19" and adjust the data value to "01" this turn off the luminance signal (Y­mute).
5. Select service adjustment "S04" and adjust data value to obtain 0.26 volts on the digital voltmeter.
6. Adjust the master screen cotrol untill raster darkens to the point where raster is barely seen.
7. Adjust service adjustments "S11" red,"S12" green and "S13" blue to obtain a good grey scale with normal whites at low brightness level.
8. Select service adjustment "S19" and reset data to "00". Select service adjustment "S03" and reset data to obtain normal color level.
9. Remove digital voltmeter. Reset master screen cotrol to obtain normal brightness range.
Sub-picture adjustment
1. Have unit receive a good local channel.
2. Make sure the customer picture control is set to maximum.
3. Enter the service mode and select service adjustment "S 01".
4. Adjust the data value to achieve normal contrast range.
Sub-Tint Adjustment
1. Have unit receive a good local channel.
2. Set customer tint control to center of it's range.
3. Enter the service mode and select service adjustment "S 02".
4. Adjust "S 02" data value to obtain normal flesh tones.
Sub-color adjustment
1. Have unit receive a good local channel.
2. Make sure the customer color control is set to center position .
3. Enter the service mode and select service adjustment "S 03".
4. Adjust "S 03"data value to obtain normal color level.
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27J-S100/180/260 CJ27S10/26
Sub-brightness adjustment
1. Have unit receive a good local channel.
2. Make sure the customer brightness control is set to center position.
3. Enter the service mode and select service adjustment "S 04".
4. Adjust "S04"data value to obtain normal brightness level.
Vertical-size and linearity adjustment
Ver-Lin-for 27J-S100/S260,CJ27S10/26
1. Have unit receive a good local channel.
2. Enter the service mode and select service adjustment "S 09".
3. While observing the top and bottom of the screen, adjust "S 09" data value to proper vertical size and linearity.
4. Using the S501 switch,adjust for the best linearity.
Vertical phase adjustment
1. Enter the service mode and select service adjustment "S 06".
2. Adjust data value to "00".
Note: This must be set "00" when changed data retrace
line will appear.
Horizontal position adjustment
1. Have unit receive a good local channel.
2. Enter the service mode and select service adjustment "S 07".
3. Adjust "S 07" data value so that picture is centered.
Caption position adjustment (horizontal)
1. Have unit receive a good local channel.
2. Enter the service mode and select service adjustment "S18".
3. A black text box appears on the screen ( see figure C ) .
4. Adjust "S18" data value so that text box is positioned in the center of the screen.
3.58MHz trap adjustment
1. Have unit receive a good local channel.
2. Enter the service mode and select service adjustment "S16" .
3. This is a two position adjustment, " 00" is ON , "01" is OFF.
4. Adjust data value to "00" for normal viewing.
Sharpness and Audio balance adjust­ments
1. Have unit receive a good local channel.
2. Enter the service mode and select "S 05" for sharpness and "S17" for balance.
Sharpness adjustments
3. Adjust data value to "28" (center of data range) for sharpness adjustment.
Audio balance adjustments
4. Adjust data value to "20" (center of data range) for Audio balance adjustment.
Figure C
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27J-S100/180/260 CJ27S10/26
MTS ADJUSTMENT
MTS level adjustment
1. Feed the following monaural signal to pin (14) of IC3001.
Monaural signal : 300Hz, 245mVrms
2. Connect the rms voltmeter to pin (39) of IC3001.
3. Enter the service mode ant select the service adjustment "M01".
4. Adjust the data so that the rms voltmeter should take the reading below. Spec. : 490;10mVrms
Stereo VCO adjustment
1. Keep the unit in no-signal state.
2. Connect the frequency counter to pin (39) of IC3001.
3. Connect a capacitor ( 100µ F, 50v) in between positive(+) side of C3005 and ground.
4. Enter the service mode and select the service adjustment"M02"
5. Adjust the data so that the frequency counter should take the reading below. Spec. : 62.94;0.75kHz
Filter adjustment
1. Feed the following stereo pilot signal to pin (14) of IC3001 . Stereo pilot signal:9.4kHz,600mVrms.
2. Enter the service mode and select the service adjustment "M03".
3. Adjust the data at the point where "OK" appears on the screen.The "OK" represents the approximate center of the adjustable range of the data.
Separation Adjustment
1. Connect the rms voltmeter to pin (39) of IC3001.
2. Receive the following composite stereo signal 1. Composite stereo signal : 30% modulation, left channel only, noise reduction on, 300Hz
3. Enter the service mode and select the service adjustment "M04".
4. Adjust the data until the AC voltage reading of the rms voltmeter is minimum.
5. Receive the following composite stereo signal 2. Stereo signal : 30% modulation, left channel only, noise reduction on, 3kHz
6. Enter the service mode and select the service adjustment "M05".
7. Adjust the data until the AC voltage reading of the rms voltmeter is minimum.
8. Take the above steps 1 thru 8 again for fine adjustment.
P-IN-P ADJUSTMENT
(FOR 27J-S260/CJ27S26) P-IN-P Y LEVEL adjustment
1. Recieve a good local channel.
2. Enter the service mode and select service adjust­ment "P01".
3. Adjust "P01" data value to obtain normal contrast level.
P-IN-P TINT adjustment
1. Recieve a good local channel.
2. Enter the service mode and select service adjust­ment "P02".
3. Adjust data value to "1B".
P-IN-P COLOR adjustment
1. Recieve a good local channel.
2. Make sure the customer color control is set to center position.
3. Enter the service mode and select service adjust­ment "P03".
4. Adjust "P03" data value to obtain normal color level.
P-IN-P Y-OFF SET adjustment
1.Recieve a good local channel.
2. Enter the service mode and select service adjust­ment "P04".
3. Adjust data value to "16".
P-IN-P H-POSITION adjustment
1. Recieve a good local channel.
2. Enter the service mode and select service adjust­ment "P05".
3. Adjust data value to "0B".
P-IN-P BURST GATE PULSE(for MAIN)
1. Recieve a good local channel.
2. Enter the service mode and select service adjust­ment "P06".
3. Adjust data value to "09".
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DESCRIPTION OF SCHEMATIC DIAGRAM
27J-S100/180/260 CJ27S10/26
NOTE:
1. The unit of resistance "ohm" is omitted (K:1000 ohms, M:1 Meg ohm).
2. All resistors are 1/8 watt, unless otherwise noted.
3. All capacitors are µF, unless otherwise noted P: µµF.
4. (G) indicates ;2% tolerance may be used.
5. Indecates line isolated ground.
6. Indecates hot ground.
VOLTAGE MEASUREMENT CONDITIONS:
1. All DC voltages are measured with DVM connected between points indicated and chassis ground, line voltage set at 120V AC and all controls set for normal picture unless otherwise indicated.
2. All voltages measured with 1000µV B & W or Color signal.
WAVEFORM MEASUREMENT CONDITIONS:
1. Photographs taken on a standard gated color bar signal, the tint setting adjusted for proper color. The wave shapes at the red, green and blue cathodes of the picture tube depend on the tint, color level and picture control.
2.:indicates waveform check points (See chart, waveforms are measured from point
indicated to chassis ground.)
å
AND SHADED ( ) COMPONENTS
= SAFETY RELATED PARTS.
ç
MARK = X-RAY RELATED PARTS.
DRGANNES MARQUES-ET HACHRES ( ) : PIECES RELATIVES A LA SECURITE . MARQUE ç :PIECS RELATIVE AUX RAYONS X.
This circuit diagram is a standard one, printed circuits may be subject to change for product improvement without prior notice. WAVEFORMS
WAVE FORMS
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