Symphonic SST4274S Schematic

SERVICE MANUAL
27" COLOR TELEVISION
SST4274S
IMPORTANT SAFETY NOTICE
Proper service and repair is important to the safe, reliable operation of all Funai Equipment. The service procedures recommended by Funai and de­scribed in this service manual are effective methods of performing service operations. Some of these service special tools should be used when and as recommended.
It is important to note that this service manual contains various CAUTIONS and NOTICES which should be carefully read in order to minimize the risk of personal injury to service personnel. The possibility exists that improper service methods may damage the equipment. It also is impo rtant to under­stand that these CAUTIONS and NOTICES ARE NOT EXHAUSTIVE. Funai could not possibly know, evaluate and advice the service trade of all con­ceivable ways in which service might be done or of the possible hazardous consequences of each way. Consequently, Funai has not undertaken any such broad evaluation. Accordingly, a servicer who uses a service proce­dure or tool which is not recommended by Funai must first use all precau­tions thoroughly so that neither his safety nor the safe operation of the equipment will be jeopardized by the service method selected.
TABLE OF CONTENTS
Specifications........................................................ 1-1
Important Safety Precautions................................ 2-1
Standard Notes for Servicing................................ 3-1
Cabinet Disassembly Instructions......................... 4-1
Electrical Adjustment Instructions......................... 5-1
Block Diagrams..................................................... 6-1
Schematic Diagrams / CBA's and Test Points...... 7-1
Schematic Diagrams............................................. 7-3
CBA Views and Test Points..................................7-11
Waveforms ..................................................... ....... 8-1
Wiring Diagram...................................................... 9-1
IC Pin Functions .................................................. 10-1
Cabinet Exploded Views...................................... 11-1
Packing Exploded Views ..................................... 11-3
Mechanical Parts List .......................................... 12-1
Electrical Parts List.............................................. 13-1

SPECIFICATIONS

<TUNER> ANT. Input ------------------- 75ohm Unbal., F type
Reference Level ----------- 20Vp-p (CRT Green Cathode) Test Input Signal ---------- 400Hz 30% modulation
Description Condition Unit Nominal Limit
1. Intermediate Freq. Picture Sound
2. Peak Picture Sens VHF
CATV
UHF
3. AFT Pull In Range (10mV input)
-
<DEFLECTION>
Description Condition Unit Nominal Limit
1. Deflection Freq. Horizontal
Vertical
2. Linearity Horizontal
Vertical
3. Over Scan
4. High Voltage
-
-
<VIDEO & CHROMA>
Description Condition Unit Nominal Limit
MHz MHz
dBµv dBµv dBµv
MHz ±2.0 ±0.7
KHz
Hz
% %
%10
KV 29
45.75
41.25 15
15 15
15.734 60
-
-
-
­30
30 40
-
-
±15 ±10
-
-
1. Misconvergence Center Side
Corner
2. Brightness APL 100% Ft-L 25 15
3. Color Temperature
4. Resolution Horizontal
<AUDIO>
Description Condition Unit Nominal Limit
1. Audio Output Power 10% THD W 1 0.8
2. Audio Distortion (w/LPF) 500mW % 2 7
3. Audio Freq. Response -3dB Hz 70~11K
Note:
Nominal specifications represent the design specifications. All units should be able to approximate these. Some will exceed and some may drop slightly below these specifications. Limit specifications represent the absolute worst condition that still might be considered acceptable. In no case should a unit fail to meet limit specifications.
All items are measured across 8 load at speaker output terminal.
-
Vertical
mm mm mm
°K 9200°K
Line Line
-
-
-
250 300
0.4
1.5
2.1
-
-
-
-
1-1 L6200SP

IMPORTANT SAFETY PRECAUTIONS

Prior to shipment from the fact ory, our products are stri ctly insp ected for recogni zed pr oduct sa fety and elec trical codes of the countries in which they are to be sold. Howev er, in order to ma intain such c ompliance, it is equally important to implement the following precautions when a set is being serviced.
Safety Precautions for TV Circuit
1. Before returning an instrument to the custom -
er, alwa ys make a safety check of the entire instru-
ment, including, but not limited to, the following items:
a. Be sure that no built-in protective devices are de-
fective and have been defeated during servicing. (1) Protective shields ar e p rovid ed o n thi s ch ass i s to protect both the technician and the customer. Correctly replace all missing protective shields, in­cluding any removed for servicing convenience. (2) When reinstalling the chassis and/or other assem­bly in the cabinet, be sure to pu t back in place all protective devices, including but not limited to, nonmetallic control knobs, insulating fishpapers, adjustment and com part ment covers/shields, and isolation resistor/capacitor networks. Do not oper-
ate this instrument or permit it to be operated without all protective devices correctly in­stalled and functioning. Servicers who defeat safety features or fail to perform safety checks may be liable for any resulting damage.
b. Be sure that there are no cabinet openings through
which an adult or child might be able to insert their fingers and contact a hazardous voltage. Such openings include, but are not limited to, ( 1) spac­ing between the picture tube and the cabinet mask, (2) excessively wide cabinet ventilation slots, and (3) an improperly fitted and/or incorrectly secured cabinet back cover.
c. Antenna Cold Check - With the instrument AC
plug removed from any AC source, connect an electrical jumper acr oss the two AC plug prongs. Place the instrument AC switch in the o n position. Connect one lead of an oh mmeter to the A C plug prongs tied together and to uch the other ohmme ­ter lead in turn to each tuner antenna input ex­posed terminal screw and, if applicable, to the coaxial connector. If the measured resistance is less than 1.0 mego hm or greater than 5 .2 mego­hm, an abnormality exists that must be corrected before the instrument is r eturne d to the cu stomer . Repeat this test with the ins trument AC switch in the off position.
d. Leakage Current Hot Check - With the instru-
ment completely reassembled, plug the AC line cord directly into a 120V AC outlet. (Do not use an isolation transformer d uring thi s test.) Use a leak-
age current tester or a me tering syst em that com ­plies with American National Standards Institute (ANSI) C101.1 Leakage Current for Appliances and Underwriters Laborat ories (UL) 1410, (50.7). With the instrument AC switc h first in the on posi ­tion and then in the o ff position, measure from a known earth ground (metal water pipe, conduit, etc.) to all exposed metal parts of the instrument (antennas, handle br ackets, metal cabi net, screw heads, metallic overlay s, control shafts, etc.), es ­pecially any exposed metal parts that offer an elec­trical return path to the chassis. Any current measured must not excee d 0.5 milli-ampere. Re ­verse the instrument power cord plug in the outlet and repeat the test.
READING SHOULD NOT BE ABOVE 0.5 mA
LEAKAGE
DEVICE
BEING
TESTED
TEST ALL EXPOSED
METAL SURFACES
ALSO TEST WITH PLUG REVERSED USING AC ADAPTER PLUG AS REQUIRED
ANY MEASUREMENTS NO T WITHIN THE LIMITS SPECIFIED HEREIN INDICATE A POTENTIAL SHOCK HAZARD THAT MUST BE ELIMINATED BEFORE RETURNING THE INSTRUMENT TO THE CUSTOMER OR BEFORE CONNECTING THE ANTENNA OR ACCESSORIES.
e. X-Radiation and High Voltage Limits - Because
the picture tube i s the prim ary potentia l source of X-radiatio n in solid- state TV receiver s, it is s pecial­ly constructed to prohibit X-radiation emissions. For continued X-radiation pr otection, the replace­ment picture tube must be the same type as the original. Also, because the picture tube shields and mounting hardware perform an X-radiation protection function, they must be correctly in place. High voltage must be mea su re d ea ch tim e s er vic -
CURRENT
TESTER
+
EARTH GROUND
_
2-1 L6115IMP
ing is performed that inv olves B+, horizontal de­flection or high voltage. Correct operation of the X­radiation protection circuits also must be recon­firmed each time they are serviced. (X-radiation protection circuits also may be called "horiz ontal disable" or "hold do wn.") R ead a nd a ppl y th e hi gh voltage limits a nd, if the chassis is so e quipped, the X-radiation protection circuit specifications giv­en on instrument labe ls and i n the P roduct S afety & X-Radiation Warning note on the service data chassis schematic. High voltage is maintained within specified limits by close tolerance safety-re­lated components/adjus tme nts in th e hig h-vo lta ge circuit. If high voltage exceeds specified limits, check each component specified on the chassis schematic and take corrective action.
2. Read and comply with all caution and safety-relat­ed notes on or inside th e receiver cabi net, on the receiver chassis, or on the picture tube.
3. Design Alteration Warning - Do not alter or add to the mechanical or electrical design of this TV re­ceiver. Design alterations and additions, including, but not limited to circuit modificatio ns and the ad­dition of items such as auxiliary audio and/or video output connections, mig ht alter the safety ch arac­teristics of this receiver and create a hazard to the user. Any design alter ations or addition s will void the manufacturer's warr anty and may make you, the servicer, responsible for personal injury or property damage resulting therefrom.
4. Picture Tube Implosion Protection Warning - The picture tube in this receiver employs integral implosion protection. For continued implosion pro­tection, replace the pic ture tube only with one of the same type numbe r. Do not rem ove, install , or otherwise handle the picture tube in any ma nner without first putting on shatterproof goggles equipped with side shields. People not so equipped must be ke pt safely away while p icture tubes are handled. Keep the picture tube away from your body. Do not handl e the pictur e tu be b y its neck. Some "in-line" picture tubes are equipped with a permanently at tached deflection yoke ; be­cause of potential hazard, do not try to remove such "permanently attached" yokes from the pic­ture tube.
5. Hot Chassis Warning -
a. Some TV receiver chassis are electrically connect-
ed directly to one conduc tor of th e AC powe r cor d and maybe safety-serviced without an isolation transformer only i f the AC power plug i s inserted so that the chassis is connected to the ground side of the AC power source. To confi rm that the AC power plug is ins erted correctly, with an AC volt­meter, measure between the chassis and a known
earth ground. If a voltage reading in excess of 1.0V is obtained, remove and reinsert the AC power plug in the opposite polarity and again measure the voltage potential between the chassis and a known earth ground.
b. Some TV receiver chassis normally have 85V
AC(RMS) between ch assis and earth ground re­gardless of the AC plug polarity. This chassis can be safety-serviced only with an isolation transform­er inserted in the power line between the receiver and the AC power so urce , for both pers onnel and test equipment protection.
c. Some TV receiver chassis have a secondary
ground system in addition to the main chassis ground. This se conda ry gro und s ystem is no t iso ­lated from the AC power line. The two ground sys­tems are electrically separated by insulation material that must not be defeated or altered.
6. Observe original lead dress. Take extra care to as­sure correct lead dress in the following areas:a. near sharp edges,b. near thermally hot parts-be sure that leads and components do not touch ther­mally hot parts, c. the AC supply,d. high voltage, and,e. antenna wir ing. Always insp ect in all ar eas for pinched, out of plac e, or frayed wiring. C heck AC power cord for damage.
7. Components, parts, and/or wiring that app ear to have overheated or are otherwise damaged should be replaced with components, parts, or wir­ing that meet origin al specifications. Additiona lly, determine the cause of ov erheating and/or dam­age and, if nece ss ar y, ta ke corre ct i ve ac ti o n to re­move any potential safety hazard.
8. Product Safety Notice - Some electrical and me­chanical parts have s pecia l safety- relat ed char ac­teristics which are often not evident from visual inspection, nor can the protection they give neces­sarily be obtained by replaci ng them with compo­nents rated for higher voltage, wattage, etc.. Parts that have special safety characteristics are identi­fied by a ( # ) on schematics and in parts lists. Use of a substitute replacement that does not have the same safety characteristics as the recommended replacement part might create sh ock, fire, and/or other hazards. The product's safety is under re­view continuously and new instructions are issued whenever appropriate . Prior to shi pment from the factory, our products are strictly inspected to con­firm they comply with the recognized product safe­ty and electrical codes of the countries in which they are to be sold. Howev er, in orde r to mai ntain such compliance , it is equally i mportant to imple ­ment the following precautions when a set is being serviced.
2-2 L6115IMP
Precautions during Servicing
A. Parts identified b y the ( # ) symbo l are c ritica l for
safety. Replace only with part number specified.
B. In addition to safety, othe r parts and assemblies
are specified for conformance with regulations ap­plying to spurious radiati on. These must also be replaced only with specified replacements.
Examples: RF converters, RF cables, noise block­ing capacitors, and noise blocking filters, etc.
C. Use specified internal wiring. Note especially:
1) Wires covered with PVC tubing
2) Double insulated wires
3) High voltage leads D. Use specified insulating materials for hazardous
live parts. Note especially:
1) Insulation Tape
2) PVC tubing
3) Spacers
4) Insulators for transistors. E. When replacing AC primary side components
(transformers, power cord, etc.), wrap ends of wires securely abo ut the terminals before so lder­ing.
F. Observe that the wires do not contact heat produc-
ing parts (heatsinks, oxide metal film resistors, fus­ible resistor s, etc.)
G. Check that replaced wires do not contact sharp
edged or pointed parts.
H. When a power cord has been replaced, check that
5~6 kg of force in any direction will not loosen it. I. Also check areas surrounding repaired locations. J. Use care that foreign objects (screws, solder drop-
lets, etc.) do not remain inside the set. K. Crimp type wire connector
The power transform er uses crimp type connec-
tors which connect the power cord and the primary
side of the transformer. When replacing the trans-
former, follow these step s carefully and precis ely
to prevent shock hazards.
Replacement procedure
1) Remove the old connector by cutti ng the wires at
a point close to the connector.
Important: Do not re-use a connector (discard it).
2) Strip about 15 mm of the insulation fro m the end s
of the wires. If the wires are stranded, twist the
strands to avoid frayed conductors.
3) Align the lengths of the wires to be connected. In­sert the wires fully into the connector.
4) Use the crimping tool to crimp the metal sleeve at the center position . Be sure to crimp fully to the complete closure of the tool.
L. When connecting or disconnecting the internal
connectors, first, discon nect the AC plug from the AC supply outlet.
2-3 L6115IMP
Safety Check after Servicing
Examine the area surrounding the repaired location for damage or deterioration. Observe that screws, parts and wires have been returned to original posi­tions. Afterwards, perform the following tests and con­firm the spec ified values in or der to verify comp liance with safety standards.
1. Clearance Distance
When replacing primary circuit components, confirm specified clearance distance (d) and ( d') between sol ­dered terminals, and between terminals and surround­ing metallic parts. (See Fig. 1)
Table 1 : Ratings for selected area
AC Line Voltage Region
110 to 130 V
Note: This table is unofficial and for reference only. Be sure to confirm the precise values.
USA or
CANADA
Clearance
Distance (d), (d')
3.2 mm
(0.126 inches)
2. Leakage Current Test
Confirm the specified (or lower) leakage current be­tween B (earth ground, power cord plu g prongs) and externally exposed accessible parts (RF terminals, antenna terminal s, vi deo and audio input and output terminals, mi crophone jacks, earphone jacks, etc.) is lower than or equal to the spe cified value in the table below.
Measuring Method : (Power ON)
Insert load Z between B (earth ground, power cord plug prongs) and exposed accessible parts. Use an AC voltmeter to measure across both terminals of load Z. See Fig. 2 and following table.
Z
1.5k
Chassis or Secondary Conductor
Primary Circuit Terminals
dd'
Exposed Accessible Part
AC Voltmeter
0.15µF
Earth Ground
B
Power Cord Plug Prongs
(High Impedance)
Fig. 1
Fig. 2
Table 2 : Leakage current ratings for selected areas
AC Line Voltage Region Load Z Leakage Current (i) Earth Ground (B) to:
0.15µF CAP. & 1.5k
110 to 130 V USA
Note: This table is unofficial and for reference only. Be sure to confirm the precise values.
RES. connected in
parallel
2-4 L6115IMP
i0.5mA rms
Exposed accessible
parts

STANDARD NOTES FOR SERVICING

Circuit Board Indications
a. The output pin of the 3 pin Regulator ICs is indicat-
ed as shown.
Top View
Out
b. For other IC s, pin 1 and every fifth pin are in dic at -
ed as shown.
Pin 1
c. The 1st pin of every male connector is indicated as
shown.
Pin 1
Input
In
Bottom View
5
10
Pb (Lead) Free Solder
Pb free mark will be found on PCBs used Pb free solder. (Refer to figure.) For PCBs with Pb free mark, be sure to use Pb free solder. For PCBs without Pb free mark, use standard solder.
Pb free mark
How to Remove / Install Flat Pack-IC
1. Removal
With Hot-Air Flat Pack-IC Desoldering Machine:
(1) Prepare the hot-air flat pack-IC desoldering ma-
chine, then apply hot air to the Flat Pack-IC (about 5 to 6 seconds). (Fig. S-1-1)
Fig. S-1-1
(2) Remove the flat pack-IC with tweez ers while ap-
plying the hot air.
(3) Bottom of the flat pack -IC is fix ed with glu e to the
CBA; when removing entire flat pack-IC, first apply soldering iron to center of the flat pack-IC and heat up. Then remove (glue will be melted). (Fig. S-1-6)
(4) Release the flat pack-IC from the CBA using twee-
zers. (Fig. S-1-6)
Caution:
1. The Flat Pack-IC shape may differ by models. Use an appropriate hot-air flat pack-IC desoldering ma­chine, whose shape matches that of the Flat Pack­IC.
2. Do no t supply hot air to the ch ip parts aroun d the flat pack-IC for over 6 seconds because damage to the chip parts may occur. Put masking tape around the flat pack-IC to protec t other par ts from damage. (F ig. S-1-2)
3-1 L14STA
3. The flat pack-IC on the CBA is affixed with glue, so be careful not to bre ak or d ama ge the f oil of each pin or the solder l ands under the IC when remov ­ing it.
With Soldering Iron:
(1) Using desoldering braid, r emove the solder from
all pins of the flat pack-IC. When you use solder flux which is applie d to al l pins o f th e flat pac k-IC, you can remove it easily. (Fig. S-1-3)
CBA
Masking Tape
Tweezers
Hot-air Flat Pack-IC Desoldering Machine
Flat Pack-IC
Fig. S-1-2
Flat Pack-IC
Desoldering Braid
Soldering Iron
Fig. S-1-3
(2) Lift each lead of the flat pack-IC up ward one by
one, using a sharp pin or wi re to which solder will not adhere (iron wire). When heating the pins, use a fine tip soldering iron or a hot air desoldering ma­chine.(Fig. S-1-4)
Sharp Pin
Fine Tip Soldering Iron
(3) Bottom of the flat pack -IC is fix ed with glu e to the
CBA; when removing entire flat pack-IC, first apply soldering iron to center of the flat pack-IC and heat up. Then remove (glue will be melted). (Fig. S-1-6)
(4) Release the flat pack-IC from the CBA using twee-
zers. (Fig. S-1-6)
With Iron Wire:
(1) Using desoldering braid, r emove the solder from
all pins of the flat pack-IC. When you use solder flux which is applie d to al l pins o f th e flat pac k-IC, you can remove it easily. (Fig. S-1-3)
(2) Affix the wire to a workbench or solid mounting
point, as shown in Fig. S-1-5.
(3) While heating the pins using a fine tip so ldering
iron or hot air blower, pull up the wire as the solder melts so as to lift the IC leads fr om the CBA con­tact pads as shown in Fig. S-1-5.
Fig. S-1-4
3-2 L14STA
(4) Bottom of the flat pack-IC is fi xed with g lue to the
CBA; when removing entire flat pack-IC, first apply soldering iron to center of the flat pack-IC and heat up. Then remove (glue will be melted). (Fig. S-1-6)
(5) Release the flat pack-IC from the CBA using twee-
zers. (Fig. S-1-6)
Note:
When using a soldering iron, care must be taken to ensure that the flat pack-IC is n ot being held by glue. When the flat pack-IC i s removed from the CBA, handle it gently because it may be damaged if force is applied.
2. Installation
(1) Using desoldering braid, r emove the solder from
the foil of each pin of the fla t pack-IC o n the CBA so you can install a replacement flat pack-IC more easily.
(2) The "I" mark on the fl at pack-IC indicates pin 1.
(See Fig. S-1-7.) Be sure this mark matches the 1 on the PCB when positioning for installation. Then pre- solder the four corners of the flat pack-IC. (See Fig. S-1-8.)
(3) Solder all pins of the flat pack-IC. Be sure that
none of the pins have solder bridges.
To Solid Mounting Point
CBA
Tweezers
Hot Air Blower
Iron Wire
Soldering Iron
Fig. S-1-5
Fine Tip Soldering Iron
Flat Pack-IC
or
Example :
Pin 1 of the Flat Pack-IC is indicated by a " " mark.
Presolder
CBA
Fig. S-1-7
Flat Pack-IC
Fig. S-1-6
Fig. S-1-8
3-3 L14STA
Instructions for Handling Semiconductors
Electrostatic breakdown of the semiconductors may occur due to a potential difference caused by electro ­static charge during unpacking or repair work.
1. Ground for Human Body
Be sure to wear a grounding band (1M) that is prop ­erly grounded to rem ove any static electricity that may be charged on the body.
2. Ground for Workbench
Be sure to place a conductive sheet or copper plate with proper grounding (1M) on the workbench or other surface, where the semiconductors are to be placed. Because the st atic electr icity charge on cloth­ing will not escape through the body grounding band, be careful to avoid contacting semiconductors with your clothing.
<Incorrect>
<Correct>
1M
CBA
Grounding Band
1M
CBA
Conductive Sheet or Copper Plate
3-4 L14STA

CABINET DISASSEMBLY INSTRUCTIONS

1. Disassembly Flowchart
This flowchart indicates the disassembly steps for the cabinet par ts, and the CBA in order to gain ac cess to item(s) to be se r vic ed. W hen r eass embling, follow the steps in reverse order. Bend, route and dress the cables as they were.
Caution !
When removing the CRT, be sure to discharge the Anode Lead of the CRT with the CRT Ground Wire before removing the Anode Cap.
[1] Rear Cabinet
[2] CRT CBA
[3] Main CBA
[4] CRT
2. Disassembly Method
Note :
(1) Order of steps in procedu re. When reas sembling,
follow the steps i n reverse or der. These n umbers are also used as the Identification (location) No. of
parts in figures. (2) Parts to be removed or installed. (3) Fig. No. showing procedure of part location (4) Identification of part to be removed, unhooked, un-
locked, released, unplugged, unclamped, o r des-
oldered.
S=Screw, P=Spring, L=Locking Tab, CN=Con-
nector, *=Unhook, Unlock, Release, Unplug, or
Desolder
2(S-2) = two Screws (S-2) (5) Refer to the following "Reference Notes in the
Table."
Reference Notes in the Table
1. Removal of the Rear Cabinet. Remove screws
7(S-1), 2(S-2) an d (S-4) t hen s lide the Rear Cabi-
net backward.
2. Removal of the CRT CBA. Disconnect CN1501
then pull the CRT CBA backward.
3. Removal of the Main CB A. Disconne ct CN571 on
the Main CBA then slide the Main CBA backward.
Removal
Step/
Loc. No.
[1]
[2] CRT CBA 4,5 CN501 2 [3] Main CBA 3,5 CN571 3 [4] CR T 4 4(S-3), Anode Cap 4
Part
Rear Cabinet
Fig.
No
1,2
Remove/*unlock/
release/unplug/
unclamp/desolder
7(S-1), 2(S-2), (S-4)
Note
1
↓↓↓
(1) (2) (3) (4) (5)
Caution:
Discharge the Anode Lead o f the CRT with the CRT Ground Wire before removing the Anode Cap.
4. Removal of the CR T. Remo ve sc rews 4(S- 3) and
Anode Cap. then slide the CRT backward.
4-1 L2712DC
S-1
S-1
S-4
S-2
S-1
[1] Rear Cabinet
S-1
S-1
S-1
S-1
Fig. 1
S-2
S-3
[3] Main CBA
[2] CRT CBA
Anode Cap
S-3
Fig. 3
S-3
S-1
S-1
[1] Rear Cabinet
S-4
S-1
Fig. 2
S-1
S-3
[4] CRT
Fig. 4
4-2 L2712DC
TV Cable Wiring Diagram
DG691 DEGAUSSING COIL
SP802
SP801
CLN802
CN691
CN802
MAIN CBA
CLN801
CN801
WH301A
AC601 AC CORD
FLYBACK TRANSFORMER
T571
WH501A
CN571
FOCUS
SCREEN
ANODE
TU11 TUNER
TO CRT GROUND
WH501B
CN1501
JK1501
WH301B
Fig. 5
4-3 L2712DC

ELECTRICAL ADJUSTMENT INSTRUCTIONS

General No te : "CBA" is abbreviation for "Circuit Board Assem­bly."
NOTE:
Electrical adjustm ent s ar e required after replacing circuit components a nd certain mechanic al parts. It is important to perform these adjustm ents only after all repairs and replacements have been com­pleted. Also, do not attempt these adjustments unless the proper equipment is available.
Test Equipment Required
1. NTSC Pattern Generator (Color Bar W/White Window, Red Color, Dot Pattern, Gray Scale, Monoscope, Multi-Burst)
2. DC Voltmeter
3. Oscilloscope: Dual-trace with 10:1 probe, V-Range:0.001~50V/Div, F-Range: DC~AC-60MHz
4. Plastic Tip Driver
5. Remote control unit: Part No. NE121UD or NE122UD
6. DC power supply 13.2V/5A
How to set up the service mode:
Service mode:
1. Use the service remote control unit.
2. Turn the power on. (Use main power on the TV unit.)
3. Press "SLEEP" button on the service remote con­trol unit. Version of m icro co mpu ter wi ll dis pl ay on the CRT. (Ex: 058-0.06)
4. Check the display on the lower left is "2641" and if it is not "2641," set it at "2641" according to "2. Ini­tial Setting."
1. +B Adjustment
Purpose: To obtain correct operation. Symptom of Misadjustment: The picture is dark and
the unit does not operate correctly.
Test Point Adj. Point Mode Input
TP601(+B)
TP300(GND)
Tape M. EQ. Spec.
--- DC Voltmeter +120±0.5V DC.
VR661 --- ---
How to make Service remo te control unit:
1.
Prepare normal remote control unit. ( NE121UD or NE122UD) Remove 3 S crews from the back lid. (Fig. 1-1)
2 . Add J1 (Jumper Wire) to the remote control CBA.
(Fig. 1-2)
SCREWS
REMOTE CONTROL UNIT
J 1
REMOTE CONTROL CBA
Part No.
Fig. 1-1
Fig. 1-2
Note: TP601, TP300(GND), VR661 --- Main CBA
1. Connect D C Volt M ete r t o TP6 01 an d TP300 (GN D).
2. Adjust VR661 so th at the voltage o f TP60 1 becomes +120±0.5V DC.
5-1 L2712EA
2. Initial Setting
General
1. Enter the Service mode. (See page 5-1)
2. Press "VOL p" button on the service remote control unit. Display changes "C/D," "7F," "LANGUAGE," "ACCESS CODE," "SOUND TYPE," "VIDEO TONE," "FM MODE," "V-OUT," "VIDEO," "AV MEMO," "STABLE SOUND," "FILTER," "500," "YUV MEMORY," "NO SIG BRT," "A-MUTE POL," and "V-MENU" cyclically when "VOL p" button is pressed.
3. To set the following each data value, press "CH o / p" buttons on the service remote control unit.
7F --- Set to "FF." LANGUAGE --- Set to "SPA/FRA." ACCESS CODE --- Set to "OFF." SOUND TYPE --- Set to "MTS." VIDEO TONE --- Set to "ON." FM-MODE --- Set to "OFF." V-OUT --- Set to "OFF." VIDEO --- Set to "V1/V2." AV MEMO --- Set to "OFF." STABLE SOUND --- Set to "OFF." FILTER --- Set to "OFF." Adjusting the monitoring time --- Set to "500." YUV MEMORY --- Set to "OFF." NO SIG BRT --- Set to "0." A-MUTE POL --- Set to "H." V-MENU --- Set to "OFF."
3. Setting for BRIGHT, CONTRAST,
COLOR, TINT, and SHARPNESS data Values
General
1. Enter the Service mode. (See page 5-1)
2. Press "MENU" button on the service remote control unit. Display changes "BRT," "CNT," "CLR," "S­CLR," "TNT," "V-TNT," "S-TNT," "SHARP," and "S-SRP" cyclically when "MENU" button is pressed.
CNT
1. Press "MENU" button on the service remote control unit. Then select "CONTRAST" (CNT) display.
2. Press "CH o/p" buttons on the service remote control unit so that the value of "CONTRAS" (CNT) becomes 84.
CLR
1. P ress "MENU" b utton on the service remote con­trol unit. Then select "COLOR" (CLR) display.
2. Press "CH o/p " buttons on the service remote control unit so that the val ue of "COLOR" (CLR) becomes 56.
S-CLR
1. P ress "MENU" b utton on the service remote con­trol unit. Then select "S-COLOR" (S-CLR) display.
2. Press "CH o/p " buttons on the service remote control unit so that the value of "S-COLOR" (S­CLR) becomes 56.
TNT
1. P ress "MENU" b utton on the service remote con­trol unit. Then select "TINT" (TNT) display.
2. Press "CH o/p " buttons on the service remote control unit so that the value of "T INT" (TNT) be­comes 58.
V-TNT
1. Press "MENU" button on the service remote con­trol unit. Then select "V-TINT" (V-TNT) display.
2. Press "CH o/p" buttons on the service remote control unit so that the value of "V- TINT" (V-TNT ) becomes 59.
S-TNT
1. Press "MENU" button on the service remote con­trol unit. Then select "S-TINT" (S-TNT) display.
2. Press "CH o/p" buttons on the service remote control unit so that the value of "S- TINT" (S-TNT ) becomes 59.
SHARP
1. P ress "MENU" b utton on the service remote con­trol unit. Then select "SHARPNESS" (SHARP) dis­play.
2. Press "CH o/p " buttons on the service remote control unit and select "47."
S-SRP
1. P ress "MENU" b utton on the service remote con­trol unit. Then select "S-SHARPNESS" (S-SRP) display.
2. Press "CH o/p " buttons on the service remote control unit and select "44."
Note: BRIGHT data value does not need to be adjust-
ed at this moment.
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4. H f0 Adjustment
Purpose: To get correct horizontal frequency.
Use service remote control unit.
1. Press "2" button on the service remote control unit. and select H-ADJ m ode. (By pressing "2" button the display will change from TV AGC to H-ADJ.)
2. Press "CH o/p" button on the service remote con- trol unit so that display will change "0" ~ "7". At this moment, Choose "4".
3. Turn the power off and on again. (Main Power but­ton on the TV unit.)
5. Black Stretch Control Adjustment
Purpose: To show the fine black color. Symptom of Misadjustment: Black color will not
appear correctly. Note: Use service remote control unit.
1. Enter the Service mode. (See page 5-1)
2. Press "6" button on the service remote control unit. "B-S" is indicated.
3. Press "CH o / p" bu ttons on the service remote con ­trol unit so that display will change "OFF," "0," and "1." Then choose "B-S OFF."
4. Press "6" button on the service remote control unit. "B-S2" is indicated.
5. Press "CH o / p" buttons on the service remote control unit so that display will change "0" and "1." Then choose "B-S2 0."
6. Turn the power off and on again, using the mai n power button on the TV unit.
7. SD Check Mode
1. Enter the Service mode. (See page 5-1)
2. Pre ss "1" button on the remote contr ol unit. The unit enter the SD-Check mode.
3. T he unit starts selecting the added channel from first channel according to the memorized CH ADD/ DELL data and CATV/TV data in RAM.
SD Check mode (Factory mode)
Press "1" buton.
7 Please wait
OSD color: Magenta
There is no SD after selecting channel.
13 Please wait
There are SD in all channel.
26 OK
OSD color: Magenta
OSD color: Magenta
30 NG
OSD color: Magenta
6. Purity Check
1. Enter the Service mode. (See page 5-1)
2. Press "7" button o n the remote control uni t. Each time pressing 7" button on the remote control unit, display changes Red mode, Green mode, Blue mode, and White mode cyclically.
3. Select White mode.
4. Turn the power off and on again. (Main power but­ton on the TV unit.)
When SD-Check starting, there is no ADD channel.
ADD nothing
OSD color: Magenta
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