Symphonic 6424FF, ST424FF Schematic

SERVICE MANUAL

24″ COLOR TELEVISION

6424FF/ST424FF

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 important 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

How to initialize the Television. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1

Block Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1

Schematic Diagrams / CBA’s and Test Points. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1

Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1

Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-1

IC Pin Function Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-1

Exploded Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-1

Mechanical Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-1

Electrical Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-1

SPECIFICATIONS

< TUNER >

ANT. Input ---------------------- 75 ohm Unbal., F type Reference Level--------------- 20 Vp-p (CRT Green Cathode) Test Input Signal -------------- 400 Hz 30% modulation

Description Condition Unit Nominal Limit

1. Intermediate Freq.

2. Peak Picture Sens

3. AFT Pull In Range (10 mV input) --- MHz ±2.0 ±0.7

Picture

Sound

VHF

CATV

UHF

MHz MHz

dBµV dBµV dBµV

45.75

41.25 15

15 15

---

--30

30 40

< DEFLECTION >

Description Condition Unit Nominal Limit

1. Deflection Freq.

2. Linearity

3. Over Scan --- % 10 ---

4. High Voltage --- kV 29 ---

Horizontal

Vert ical

Horizontal

Vert ical

kHz

% %

15.734 60

---

±15 ±10

< VIDEO & CHROMA >

Description Condition Unit Nominal Limit

1. Misconvergence

Center

Side

Corner

mm mm mm

---

0.4

1.5

2.1

2. Brightness APL 100% Ft-L 30 24

3. Color Temperature --- °K 9200 °K ---

4. Resolution

Horizontal

Vert ical

Line Line

250 300

---

< AUDIO >

All items are measured across 8 Ω load at speaker output terminal.

Description Condition Unit Nominal Limit

1. Audio Output Power 10% THD W 1 0.8

2. Audio Distortion (w/LPF) 500 mW % 2 7

3. Audio Freq. Response -3 dB Hz 70 ~ 11 k ---

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.

1-1 L3400SP

IMPORTANT SAFETY PRECAUTIONS

Prior to shipment from the factory, our products are strictly inspected for recognized product safety and electrical codes of the countries in which they are to be sold. However, in order to maintain such compliance, 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

customer, always make a safety check of the

entire instrument, including, but not limited to, the following items:

a. Be sure that no built-in protective devices are

defective and have been defeated during servicing. (1) Protective shields are provided on this chassis 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 put back in place all protective devices, including but not limited to, nonmetallic control knobs, insulating fishpapers, adjustment and compartment covers/shields, and isolation resistor/capacitor networks. Do not operate 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 across the two AC plug prongs. Place the instrument AC switch in the on position. Connect one lead of an ohmmeter to the AC plug prongs tied together and touch the other ohmmeter 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 megohm or greater than 5.2 megohm, an abnormality exists that must be corrected before the instrument is returned to the customer. Repeat this test with the instrument AC switch in the off position.

d. Leakage Current Hot Check - With the

instrument completely reassembled, plug the

AC line cord directly into a 120 V AC outlet. (Do not use an isolation transformer during this test.) Use a leakage current tester or a metering system that complies with American National Standards Institute (ANSI) C101.1 Leakage Current for Appliances and Underwriters Laboratories (UL) 1410, (50.7). With the instrument AC switch first in the on position and then in the off position, measure from a known earth ground (metal water pipe, conduit, etc.) to all exposed metal parts of the instrument (antennas, handle brackets, metal cabinet, screw heads, metallic overlays, control shafts, etc.), especially any exposed metal parts that offer an electrical return path to the chassis. Any current measured must not exceed 0.5 milli-ampere. Reverse 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 NOT 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 is the primary potential source of X-radiation in solid-state TV receivers, it is specially constructed to prohibit X-radiation emissions. For continued Xradiation protection, the replacement picture tube must be the same type as the original.

CURRENT

TESTER

EARTH GROUND

2-1 TVN_ISP

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 measured each time servicing is performed that involves B+, horizontal deflection or high voltage. Correct operation of the X-radiation protection circuits also must be reconfirmed each time they are serviced. (X-radiation protection circuits also may be called “horizontal disable” or “hold down.”) Read and apply the high voltage limits and, if the chassis is so equipped, the Xradiation protection circuit specifications given on instrument labels and in the Product Safety & X-Radiation Warning note on the service data chassis schematic. High voltage is maintained within specified limits by close tolerance safety-related components/ adjustments in the high-voltage 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 safetyrelated notes on or inside the receiver cabinet, 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 modifications and the addition of items such as auxiliary audio and/or video output connections, might alter the safety characteristics of this receiver and create a hazard to the user. Any design alterations or additions will void the manufacturer's warranty 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 picture tube only with one of the same type number. Do not remove, install, or otherwise handle the picture tube in any manner without first putting on shatterproof goggles equipped with side shields. People not so equipped must be kept safely away while picture tubes are handled. Keep the picture tube away from your body. Do not handle the picture tube by its neck. Some “in-line” picture tubes are equipped with a permanently attached 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

connected directly to one conductor of the AC power cord and maybe safety-serviced without

an isolation transformer only if the AC power plug is inserted so that the chassis is connected to the ground side of the AC power source. To confirm that the AC power plug is inserted 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 chassis 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 source, for both personnel and test equipment protection.

c. Some TV receiver chassis have a secondary

ground system in addition to the main chassis ground. This secondary ground system is not isolated 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 wiring. Always inspect in all areas for pinched, out of place, or frayed wiring. Check AC power cord for damage.

7. Components, parts, and/or wiring that appear to have overheated or are otherwise damaged should be replaced with components, parts, or wiring that meet original specifications. Additionally, determine the cause of overheating and/or damage and, if necessary, take corrective action to remove any potential safety hazard.

8. Product Safety Notice - Some electrical and mechanical parts have special safety-related characteristics which are often not evident from visual inspection, nor can the protection they give necessarily be obtained by replacing 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 shock, fire, and/or other hazards. The product's safety is under review continuously and new instructions are issued whenever appropriate. Prior to shipment from the factory, our products are strictly inspected to confirm they comply with the recognized product safety and electrical codes

2-2 TVN_ISP

of the countries in which they are to be sold. However, in order to maintain such compliance, it is equally important to implement the following precautions when a set is being serviced.

Precautions during Servicing

A. Parts identified by the # symbol are critical for

safety. Replace only with part number specified.

B. In addition to safety, other parts and assemblies

are specified for conformance with regulations applying to spurious radiation. 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 about the terminals before soldering.

F. Observe that the wires do not contact heat

producing parts (heat sinks, oxide metal film resistors, fusible resistors, 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

droplets, etc.) do not remain inside the set.

K. Crimp type wire connector

The power transformer uses crimp type connectors which connect the power cord and the primary side of the transformer. When replacing the transformer, follow these steps carefully and precisely to prevent shock hazards. Replacement procedure

1) Remove the old connector by cutting 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 from the ends 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, disconnect the AC plug from the AC supply outlet.

2-3 TVN_ISP

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 specified values in order to verify compliance with safety standards.

1. Clearance Distance

When replacing primary circuit components, confirm specified clearance distance (d) and (d') between soldered terminals, and between terminals and surrounding metallic parts. (See Fig. 1)

Table 1: Ratings for selected area

Chassis or Secondary Conductor

Primary Circuit Terminals

AC Line Voltage Region

110 to 130 V

Note: This table is unofficial and for reference only. Be

sure to confirm the precise values.

U.S.A. 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 plug prongs) and externally exposed accessible parts (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks, etc.) is lower than or equal to the specified 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.

dd'

Fig. 1

Exposed Accessible Part

AC Voltmeter (High Impedance)

Earth Ground

Power Cord Plug Prongs

Fig. 2

Table 2: Leakage current ratings for selected areas

AC Line Voltage Region Load Z Leakage Current (i) Earth Ground (B) to:

110 to 130 V

Note: This table is unofficial and for reference only. Be sure to confirm the precise values.

U.S.A. or

Canada

0.15 µF CAP. & 1.5 kΩ

RES. Connected in parallel

2-4 TVN_ISP

i ≤ 0.5 mA rms

Exposed accessible

parts

STANDARD NOTES FOR SERVICING

Circuit Board Indications

1. The output pin of the 3 pin Regulator ICs is indicated as shown.

Top View

Out

2. For other ICs, pin 1 and every fifth pin are indicated as shown.

Pin 1

3. The 1st pin of every male connector is indicated as shown.

Pin 1

Input

Bottom View

Pb (Lead) Free Solder

Pb free mark will be found on PCBs which use 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 machine, 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 tweezers while applying the hot air.

3. Bottom of the flat pack-IC is fixed with glue 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 tweezers. (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 Pack-IC.

2. Do not supply hot air to the chip parts around 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 protect other parts from damage. (Fig. S-1-2)

3-1 TVN_SN

3. The flat pack-IC on the CBA is affixed with glue, so be careful not to break or damage the foil of each pin or the solder lands under the IC when removing it.

With Soldering Iron:

1. Using desoldering braid, remove the solder from all pins of the flat pack-IC. When you use solder flux which is applied to all pins of the flat pack-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 upward one by one, using a sharp pin or wire 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

4. Release the flat pack-IC from the CBA using tweezers. (Fig. S-1-6)

Fig. S-1-4

3-2 TVN_SN

With Iron Wire:

1. Using desoldering braid, remove the solder from all pins of the flat pack-IC. When you use solder flux which is applied to all pins of the flat pack-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 soldering iron or hot air blower, pull up the wire as the solder melts so as to lift the IC leads from the CBA contact pads as shown in Fig. S-1-5.

4. Bottom of the flat pack-IC is fixed with glue 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 tweezers. (Fig. S-1-6)

Note: When using a soldering iron, care must be

taken to ensure that the flat pack-IC is not being held by glue. When the flat pack-IC is removed from the CBA, handle it gently because it may be damaged if force is applied.

Hot Air Blower

2. Installation

1. Using desoldering braid, remove the solder from the foil of each pin of the flat pack-IC on the CBA so you can install a replacement flat pack-IC more easily.

2. The “●” mark on the flat 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 presolder 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.

Example :

Pin 1 of the Flat Pack-IC is indicated by a " " mark.

Fig. S-1-7

To Solid Mounting Point

CBA

Tweezers

Iron Wire

Soldering Iron

Fig. S-1-5

Fine Tip Soldering Iron

Flat Pack-IC

Presolder

Flat Pack-IC

CBA

Fig. S-1-8

Fig. S-1-6

3-3 TVN_SN

Instructions for Handling Semiconductors

Electrostatic breakdown of the semi-conductors may occur due to a potential difference caused by electrostatic charge during unpacking or repair work.

1. Ground for Human Body

Be sure to wear a grounding band (1 MΩ) that is properly grounded to remove 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 (1 MΩ) on the workbench or other surface, where the semi-conductors are to be placed. Because the static electricity charge on clothing will not escape through the body grounding band, be careful to avoid contacting semi-conductors with your clothing.

1MΩ

CBA

Grounding Band

1MΩ

CBA

Conductive Sheet or Copper Plate

3-4 TVN_SN

CABINET DISASSEMBLY INSTRUCTIONS

1. Disassembly Flowchart

This flowchart indicates the disassembly steps for the cabinet parts, and the CBA in order to gain access to item(s) to be serviced. When reassembling, 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

Removal

Step/

Loc.

No.

[1]

Part

Rear Cabinet

Remove/*Unhook/

Fig.

No.

D1 D2

Unlock/Release/

Unplug/Unclamp/

Desolder

6(S-1), (S-2), 2(S-3) 1

Note

Note:

(1) Order of steps in procedure. When reassembling,

follow the steps in reverse order. These numbers 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 parts to be removed, unhooked,

unlocked, released, unplugged, unclamped, or desoldered. P = Spring, L = Locking Tab, S = Screw, CN = Connector * = Unhook, Unlock, Release, Unplug, or Desolder e.g. 2(S-2) = two Screws (S-2), 2(L-2) = two Locking Tabs (L-2)

(5) Refer to the following "Reference Notes in the

Table."

Reference Notes in the Table

1. Removal of the Rear Cabinet: Remove screws 6(S-1), (S-2) and 2(S-3) then slide the Rear Cabinet backward.

2. Removal of the CRT CBA: Disconnect CN1501 then pull the CRT CBA backward.

3. Removal of the Main CBA: Disconnect CN571 on the Main CBA then slide the Main CBA backward.

4. CAUTION: Discharge the Anode Lead of the CRT with the CRT Ground Wire before removing the Anode Cap. Removal of the CRT: Remove screws 4(S-4) and Anode Cap. then slide the CRT backward.

[2] CRT CBA

[3] Main CBA

[4] CRT D4 4(S-4), Anode Cap 4

↓

(1)

↓

(2)

CN1501 2

D5 D3

CN571 3

↓

(3)

↓

(4)

↓

(5)

4-1 L3420DC

S-1

ANT. IN

S-2

S-3

[1] Rear Cabinet

S-1

S-1S-1

Fig. D1

S-1

S-3

S-2

S-4

[3] Main CBA

[2] CRT CBA

Anode Cap

S-4

Fig. D3

S-4

S-1

[1] Rear Cabinet

S-1

Fig. D2

S-4

[4] CRT

Fig. D4

4-2 L3420DC

TV Cable Wiring Diagram

DG691 DEGAUSSING COIL

SP802

SP801

CLN802

CN802

CN691

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. D5

4-3 L3420DC

ELECTRICAL ADJUSTMENT INSTRUCTIONS

General Note: “CBA” is abbreviation for “Circuit Board Assembly.”

Note: Electrical adjustments are required after

replacing circuit components and certain mechanical parts. It is important to perform these adjustments 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: 0.001~50 V/Div, F-Range: DC~AC-60 MHz

4. Plastic Tip Driver

5. Remote control unit: Part No. N0108UD, N0132UD, NE121UD or NE122UD

6. DC power supply 13.2V/5A

How to make Service remote control unit:

1. Prepare normal remote control unit. (Part No. N0108UD, N0132UD, NE121UD or NE122UD) Remove 3 Screws from the back lid. (Fig. 1-1)

Screws

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 micro computer will display on the CRT. (Ex: 058-0.06)

4. Check the display on the lower left is “3641” and if it is not “3641,” set it at “3641” according to "Initial Setting" on page 5-2.

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±0.5 V DC.

Note: TP601, TP300(GND), VR661 --- Main CBA

1. Connect DC Volt Meter to TP601 and TP300(GND).

2. Adjust VR661 so that the voltage of TP601 becomes +120±0.5 V DC.

VR661 --- ---

Remote control unit (bottom)

2. Added J1 (Jumper Wire) to the remote control CBA. (Fig. 1-2)

J 1

Remote Control CBA

Fig. 1-1

Fig. 1-2

5-1 L3420EA

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 “ON.”

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, S-COLOR, TINT, V-TINT, S-TINT, SHARP, and S-SHARP 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," "S-CLR," "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 “CONTRAST” (CNT) becomes 84.

CLR

1. Press [MENU] button 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 value of “COLOR” (CLR) becomes 56.

S-CLR

1. Press [MENU] button 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. Press [MENU] button 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 “TINT” (TNT) becomes 58.

V-TN T

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-TINT

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. Press [MENU] button on the service remote control unit. Then select “SHARP” (SHARP) display.

2. Press [CH o / p] buttons on the service remote control unit and select “40.”

S-SHARP

1. Press [MENU] button on the service remote control unit. Then select “S-SHARP” (S-SRP) display.

2. Press [CH o / p] buttons on the service remote control unit and select “42.”

Note: BRIGHT data value does not need to be

adjusted at this moment.

5-2 L3420EA

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