Zenith HD SAT520 Service Manual

1-3

CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY, NEVER PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFACTURER’S APPROVAL. UNAUTHORIZED MODIFICATIONS WILL NOT ONLY VOID THE WARRANTY, BUT MAY LEAD TO YOUR BEING LIABLE FOR ANY RESULTING PROPERTY DAMAGE OR USER INJURY.

SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU ARE THOROUGHLY FAMILIAR WITH ALL OF THE FOLLOWING SAFETY CHECKS AND SERVICING GUIDELINES. TO DO OTHERWISE, INCREASES THE RISK OF POTENTIAL HAZARDS AND INJURY TO THE USER.

WHILE SERVICING, USE AN ISOLATION TRANSFORMER FOR PROTECTION FROM A.C. LINE SHOCK.

SAFETY CHECKS

AFTER THE ORIGINAL SERVICE PROBLEM HAS BEEN CORRCTED. A CHECK SHOULD BE MADE OF THE FOLLOWING.

SUBJECT : FIRE & SHOCK HAZARD

1. BE SURE THAT ALL COMPONENTS ARE POSITIONED IN SUCH A WAY AS TO AVOID POSSIBILITY OF ADJACENT COMPONENT SHORTS. THIS IS ESPECIALLY IMPORTANT ON THOSE MODULES WHICH ARE TRANSPORTED TO AND FROM THE REPAIR SHOP.

2. NEVER RELEASE A REPAIR UNLESS ALL PROTECTIVE DEVICES SUCH AS INSULATORS, BARRIERS, COVERS, SHIELDS, STRAIN RELIEFS, POWER SUPPLY CORDS, AND OTHER HARDWARE HAVE BEEN REINSTALLED PER ORIGINAL DESIGN. BE SURE THAT THE SAFETY PURPOSE OF THE POLARIZED LINE PLUG HAS NOT BEEN DEFEATED.

3. SOLDERING MUST BE INSPECTED TO DISCOVER POSSIBLE COLD SOLDER JOINTS, SOLDER SPLASHES OR SHARP SOLDER POINTS. BE CERTAIN TO REMOVE ALL LOOSE FOREIGN PARTICLES.

4. CHECK FOR PHYSICAL EVIDENCE OF DAMAGE OR DETERIORATION TO PARTS AND COMPONENTS. FOR FRAYED LEADS, DAMAGED INSULATION (INCLUDING A.C. CORD). AND REPLACE IF NECESSARY FOLLOW ORIGINAL LAYOUT, LEAD LENGTH AND DRESS.

5. NO LEAD OR COMPONENT SHOULD TOUCH A RECIVING TUBE OR A RESISTOR RATED AT 1 WATT OR MORE. LEAD TENSION AROUND PROTRUNING METAL SURFACES MUST BE AVOIDED.

6. ALL CRITICAL COMPONENTS SUCH AS FUSES, FLAMEPROOF RESISTORS, CAPACITORS, ETC. MUST BE REPLACED WITH EXACT FACTORY TYPES, DO NOT USE REPLACEMENT COMPONENTS OTHER THAN THOSE SPECIFIED OR MAKE UNRECOMMENDED CIRCUIT MODIFICATIONS.

7. AFTER RE-ASSEMBLY OF THE SET ALWAYS PERFORM AN A.C. LEAKAGE TEST ON ALL EXPOSED METALLIC PARTS OF THE CABINET, (THE CHANNEL SELECTOR KNOB, ANTENNA TERMINALS. HANDLE AND SCREWS) TO BE SURE THE SET IS SAFE TO OPERATE WITHOUT DANGER OF ELECTRICAL SHOCK. DO NOT USE A LINE ISOLATION TRANSFORMER DURING THIS TEST USE AN A.C. VOLTMETER, HAVING 5000 OHMS PER VOLT OR MORE SENSITIVITY, IN THE FOLLOWING MANNER; CONNECT A 1500 OHM 10 WATT RESISTOR, PARALLELED BY A .15 MFD. 150.V A.C TYPE CAPACITOR BETWEEN A KNOWN GOOD EARTH GROUND (WATER PIPE, CONDUIT, ETC.) AND THE EXPOSED METALLIC PARTS, ONE AT A TIME. MEASURE THE A.C. VOLTAGE ACROSS THE COMBINATION OF 1500 OHM RESISTOR AND .15 MFD CAPACITOR. REVERSE THE A.C. PLUG AND REPEAT A.C. VOLTAGE MEASUREMENTS FOR EACH EXPOSED METALLIC PART. VOLTAGE MEASURED MUST NOT EXCEED 75 VOLTS R.M.S. THIS CORRESPONDS TO 0.5 MILLIAMP A.C ANY VALUE EXCEEDING THIS LIMIT CONSTITUTES A POTENTIAL SHOCK HAZARD AND MUST BE CORRECTED IMMEDIATELY.

SUBJECT: GRAPHIC SYMBOLS

THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED “DANGEROUS VOLTAGE” THAT MAY BE OF SUFFICIENT MAG- NITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK.

THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE.

SUBJECT : X-RADIATION

1. BE SURE PROCEDURES AND INSTRUCTIONS TO ALL SERVICE PERSONNEL COVER THE SUBJECT OF X-RADIATION. THE ONLY POTENTIAL SOURCE OF X-RAYS IN CURRENT T.V. RECEIVERS IS THE PICTURE TUBE. HOWEVER, THIS TUBE DOES NOT EMIT X-RAYS WHEN THE HIGH VOLTAGE IS AT THE FACTORY SPECIFIED LEVEL. THE PROPER VALUE IS GIVEN IN THE APPLICABLE SCHEMATIC. OPERATION AT HIGHER VOLTAGES MAY CAUSE A FAILURE OF THE PICTURE TUBE OR HIGH VOLTAGE SUPPLY AND, UNDER CERTAIN CIRCUMSTANCES, MAY PRODUCE RADIATION IN EXCESS OF DESIRABLE LEVELS.

2. ONLY FACTORY SPECIFIED C.R.T. ANODE CONNECTORS MUST BE USED. DEGAUSSING SHIELDS ALSO SERVE AS X-RAY SHIELD IN COLOR SETS, ALWAYS RE-INSTALL THEM.

3. IT IS ESSNTIAL THAT SERVICE PERSONNEL HAVE AVAILABLE AN ACCURATE AND RELIABLE HIGH VOLTAGE METER. THE CALIBRA TION OF THE METER SHOULD BE CHECKED PERIODICALLY AGAINST A REFERENCE STANDARD, SUCH AS THE ONE AVAILABLE AT YOUR DISTRIBUTOR.

4. WHEN THE HIGH VOLTAGE CIRCUITRY IS OPERATING PROPERLY THERE IS NO POSSIBILITY OF AN X-RADIATION PROBLEM. EVERY TIME A COLOR CHASSIS IS SERVICED. THE BRIGHTNESS SHOULD BE RUN UP AND DOWN 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, WE SUGGEST THAT YOU AND YOUR SERVICE ORGANIZATION REVIEW TEST PROCEDURES SO THAT VOLTAGE REGULATION IS ALWAYS CHECKED AS A STANDARD SERVICING PROCEDURE. AND THAT THE HIGH VOLTAGE READING BE RECORDER ON EACH CUSTOMER’S INVOICE.

5. WHEN TROUBLESHOOTING AND MAKING TEST MEASUREMENTS IN A PRODUCT WITH A PROBLEM OF EXCESSIVE HIGH VOLTAGE, AVOID BEING UNNECESSARILY CLOSE TO THE PICTURE TUBE AND THE HIGH VOLTAGE SUPPLY. DO NOT OPERATE THE PRODUCT LONGER THAN IS NECESSARY TO LOCATE THE CAUSE OF EXCES SIVE VOLTAGE.

6. REFER TO HV. B+ AND SHUTDOWN ADJUSTMENT PROCEDURES DESCRIBED IN THE APPROPRIATE SCHEMATIC AND DIAGRAMS (WHERE USED).

SUBJECT: IMPLOSION

1. ALL DIRECT VIEWED PICTURE TUBES ARE EQUIPPED WITH AN INTE GRAL IMPLOSION PROTECTION SYSTEM, BUT CARE SHOULD BE TAKEN TO AVOID DAMAGE DURING INSTALLATION, AVOID SCRATCHING THE TUBE. IF SCRATCHED REPLACE IT.

2. USE ONLY RECOMMENDED FACTORY REPLACEMENT TUBES.

SUBJECT : TIPS ON PROPER INSTALLATION

1. NEVER INSTALL ANY PRODUCT IN A CLOSED-IN RECESS, CUBBYHOLE OR CLOSELY FITTING SHELF SPACE. OVER OR CLOSE TO HEAT DUCT, OR IN THE PATH OF HEATED AIR FLOW.

2. AVOID CONDITIONS OF HIGH HUMIDITY SUCH AS: OUTDOOR PATIO INSTALLATIONS WHERE DEW IS A FACTOR, NEAR STEAM RADIATORS WHERE STEAM LEAKAGE IS A FACTOR, ETC.

3. AVOID PALCEMENT WHERE DRAPERIES MAY OBSTRUCT REAR VENTING. THE CUSTOMER SHOULD ALSO AVOID THE USE OF DECORATIVE SCARVES OR OTHER COVERINGS WHICH MIGHT OBSTRUCT VENTILATION.

4. WALL AND SHELF MOUNTED INSTALLATIONS USING A COMMERCIAL MOUNTING KIT. MUST FOLLOW THE FACTORY APPROVED MOUNTING INSTRUCTIONS A PRODUCT MOUNTED TO A SHELF OR PLATFORM MUST RETAIN ITS ORIGINAL FEET (OR THE EQUIVALENT THICKNESS IN SPACERS) TO PROVIDE ADEQUATE AIR FLOW ACROSS THE BOTTOM, BOLTS OR SCREWS USED FOR FASTENERS MUST NOT TOUCH ANY PARTS OR WIRING. PERFORM LEAKAGE TEST ON CUSTOMIZED INSTALLATIONS.

5. CAUTION CUSTOMERS AGAINST THE MOUNTING OF A PRODUCT ON SLOPING SHELF OR A TILTED POSITION, UNLESS THE PRODUCT IS PROPERLY SECURED.

6. A PRODUCT ON A ROLL-ABOUT CART SHOULD BE STABLE ON ITS MOUNTING TO THE CART. CAUTION THE CUSTOMER ON THE HAZARDS OF TRYING TO ROLL A CART WITH SMALL CASTERS ACROSS THRESHOLDS OR DEEP PILE CARPETS.

7. CAUTION CUSTOMERS AGAINST THE USE OF A CART OR STAND WHICH HAS NOT BEEN LISTED BY UNDERWRITERS LABORATORIES, INC. FOR USE WITH THEIR SPECIFIC MODEL OF TELEVISION RECEIVER OR GENERICALLY APPROVED FOR USE WITH T.V.’S OF THE SAME OR LARGER SCREEN SIZE.

8. CAUTION CUSTOMERS AGAINST THE USE OF EXTENSION CORDS, EXPLAIN THAT A FOREST OF EXTENSIONS SPROUTING FROM A SINGLE OUTLET CAN LEAD TO DISASTROUS CONSEQUENCES TO HOME AND FAMILY.

PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS

A.C. VOLTMETER

GOOD EARTH GROUND SUCH AS THE WATER PIPE. CONDUIT. ETC

PLACE THIS PROBE ON EACH EXPOSED METAL PART

1-4

SERVICING PRECAUTIONS

CAUTION : Before servicing the STB covered by this service data and its supplements and addends, read and follow the SAFETY PRECAUTIONS. NOTE : if unforeseen circumstances create conflict between the following servicing precautions and any of the safety precautions in this publications, always follow the safety precautions.

Remembers Safety First:

General Servicing Precautions

1. Always unplug the STB AC power cord from the AC power source before: (1) Removing or reinstalling any component, circuit board,

module, or any other assembly.

(2) Disconnection or reconnecting any internal electrical

plug or other electrical connection.

(3) Connecting a test substitute in parallel with an elec-

trolytic capacitor. Caution : A wrong part substitution or incorrect polarity installation of electrolytic capacitors may result in an explosion hazard.

2. Do not spray chemicals on or near this STB or any of its assemblies.

3. Unless specified otherwise in this service data, clean electrical contacts by applying an appropriate contact cleaning solution to the contacts with a pipe cleaner, cotton-tipped swab, or comparable soft applicator. Unless specified otherwise in this service data, lubrication of contacts is not required.

4. Do not defeat any plug/socket B+ voltage interlocks with whitch instruments covered by this service manual might be equipped.

5. Do not apply AC power to this STB and/or any of its electrical assemblies unless all solid-state device heat sinks are cerrectly installed.

6. Always connect test instrument ground lead to the appropriate ground before connection the test instrument positive lead. Always remove the test instrument ground lead last.

Insulation Checking Procedure

Disconnect the attachment plug from the AC outlet and turn the power on. Connect an insulation resistance meter(500V) to the blades of the attachment plug. The insulation resistance between each blade of the attachment plug and accessible conductive parts (Note 1) should be more than 1Mohm. Note 1 : Accessible Conductive Parts including Metal panels, Input terminals, Earphone jacks, etc.

Electrostatically Sensitive (ES) Devices

Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field effect transistors and semiconductor chip components. The following techniques should be used to help reduce the incidence of component damage caused by static electricity.

1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device, which should be removed for potential shock reasons prior to applying power to the unit under test.

2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.

3. Use only a grouned-tip soldering iron to solder or unsolder ES devices.

4. Use only an anti-static solder removal device. Some solder removal devices not classified a “anti-static” can generate electrical charges sufficient to damage ES devices.

5. Do not use freon-propelled chemicals. These can generate electrical charge sufficient to damage ES devices.

6. Do not remove a replacement ES device from its protec tive package until immediately before you are ready to install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil, or comparable conductive material).

7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material to the chassis or circuit assembly into which the device will be installed.

Caution : Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.

8. Minimize bodily motions when handling unpackaged replacement ES devices. (Normally harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity sufficient to damage an ES device.)

2-2

EXPLODED VIEWS

1. Cabinet and Main Frame Section

463

280

260

A42

A49

A46

A44

250

320

463

457

465

466

452

A43

452

463

300

BCD

2-32-3

2.Packing Accessory Section

808

804

803

801

900

802

803

813

S-VIDEO CABLE

806

RF CABLE(2EA)

822

SMART CARD

823

TELEPHONE LINE

820

COMPONENT CABLE

PACKING SHEET

PACKING

BATTERY

REMOCON

BOX CARTONX

OWNER'S MANUAL

PACKING

3-5

ELECTRICAL TROUBLESHOOTING GUIDE

1. POWER(SMPS) CIRCUIT

YES

(1) No 3.8VA

Check or Replace the D129, D130.

YES

(2) No 24VA (TO CAP, DRUM MOTOR)

YES

(3) No 30VA

NO 3.8VA.

Is the F101 normal?

Is the YH01 normal?

Is the BD101 normal?

Is Vcc(14~22V) supplied to IC101 Pin3?

Are the D121/D122 normal?

Is there about 2.5V at the IC103 Pin1?

Is the D129/D130 normal?

Is the D125 normal?

YES

Power in Main PCB is short?

Replace the F101.

(Use the same Fuse)

Replace the BD101.

Replace the TH01.

Is the D102 normal?

Check or Replace the D102.

Replace the D121/D122.

Replace the D106.

Replace the D129/D130.

Replace the D125.

Replace the D124.

NO 30VA.

Is there about 30V at the IC151 Pin1?

Check or Replace the Q151.

Check or Replace the D129/D130.

Is there about 30V at the IC151 Pin1?

Check or Replace the IC151.

Is the D124 normal?

NO 24VA.

NO 30VA.

Is the F103 normal?

Is there about 33V at the IC152 Pin1?

Is the ZD152 normal?

Replace the F103. (Use the same Fuse)

Check or Replace the D126.

Check or Replace the ZD152.

YES

Check or Replace the ZD152.

(4) No 30VA

3-6

3-7

2. Audio Troubleshooting Flow

YES

NOYES

Is 3.3V supplied to the pin 77 and 78 of IC701?

Is 27MHz Clock input into the pin 36 of IC701? Fig01

Is 33MHz Clock is output from the pin 26 of IC701? Fig02

(1) NO ATSC Audio

Is 27MHz Clock is output from the Pin 3 of IC603

Check R702, C707, C708

Is the pin 59 of IC701 is grounded?

Is 18.432MHz clock output from the pin 67 of IC701? Fig05

Check R701, C703, C704

Is Data output from the pin 73 of IC701? Fig06

Is 3.072MHz clock output from the pin 63 of IC701? Fig07

Is 48kHz clock output from the pin 64 of IC701? Fig08

Check the surroundings of IC701

Check the Power Supply Part

Is pulse input into the pin 40 and 41 of IC701? Fig03, Fig04

Is Logic Low Input into the pin 1 of IC711 and Logic High into the pin 1 of IC503 respectively?

Check the pin 56, 36 of the IC201.

Check IC503, IC711

Check

IC500

Are pulses input into the pin 3, 6 of IC503?

1.1 Check IC701 and Surroundings

3-8

Fig.01 Fig.02 Fig.03

Fig.04 Fig.05 Fig.06

Fig.07 Fig.08

3-9

Fig.09

YES

Is data pulse input into the pin 6 of IC801?

Is 48kHz clock is input into the pin 4 of IC801?

Are analog audio output from the Pin 28, 29 of IC801? Fig09

Check IC702 and surroundings

1.2 Check MSP4448G and Surroundings

Is 5V supplied to the pin 10, 16, 49, 63 of IC801?

Check Power Supply Part

Is 8V supplied to the pin 31 of IC801?

Is 10V is supplied to the pin of IC805?

Is 18.432MHz Clock input into the Pin 54, 55 of IC801?

Check Power Supply Part

Check IC713

3-10

1.3 Check IC804 and Surroundings

YES

1.4 Check Output Jack and Surroundings

Is analog audio signal output from The pin 1, 7 of IC804?

Check IC804 and surroundings

Is 9V supplied to the pin 8 of IC804?

Check Power Supply Part

Check Q803, Q804, Q805, Q806, JA600 and their surroundings

(2) No DirecTV Audio

YES

Is ATSC audio OK?

Check the pin 56, 36 of

the IC201.

Is pulse input into the pin 39, 40 of

IC503?

Check IC503, IC711 and their

Surroundings.

Check IC1950 and surroundings

Is Logic Low Input into the pin 1 of

IC711 and IC503?

3-11

YES

(3) No NTSC Audio

Is SIF signal input into the pin 50 of IC801? Fig10

Check TU300

Is SIF signal input into the Base of Q304?

Are ATSC & DirecTV Audio OK?

Check Q304

Is analog audio signal output from the pin 17, 18 of IC801?

Check IC801 and surrounding

Fig.10

3-12

(4) No SPDIF Out for ATSC & DirecTV

Is SPDIF pulse output from the pin 51 of IC701? Fig11

Is 5V supplied into the pin 2 of JA702?

Check JA702 and surrounding

YES

Check IC701 and surrounding

Is ATSC & DirecTV Audio OK?

YES

Is SPDIF pulse output from the pin 4 of IC710?

YES

Check IC710 and surrounding

Check Power Supply Part

Fig.11

3-13

YES

(5) No SPDIF for NTSC

Is data pulse output from the pin 5 of IC801?

Check IC801

Is ATSC & DirecTV Audio OK?

Is 18.432MHz clock output from the pin 57 of IC801? Fig12

Check IC801

Is ATSC & DirecTV SPDIF OK?

Is 18.432MHz clock output from the pin 3 of IC713? Fig13

Check IC713

Is NTSC Audio OK?

Is Logic Low input into the pin 19 of IC713?

Is Logic Low input into the pin 64 of IC201?

Check IC201

Is analog audio output from the pin 25, 26 of IC801?

Check IC801

3-14

Fig.12 Fig.13

3-15

YES

(6) No 3/4 RF Audio

Is ATSC & DirecTV Audio OK?

Is ATSC & DirecTV & NTSC SPDIF OK?

Is analog audio output from the pin 18 of IC801?

Check IC801

Is analog audio output from the Emitter of Q802?

Check Q802

Check TU301

3-16

3. DIRECTV FRONT PANEL Troubleshooting Flow

(1) If front panel board is not working

Is the IC -28, -24, -21.5V power

supplied normally?

Does the clock #1 operate normally?

Does the signal #2 operate normally?

Check IC100(5) clock waveform

: See Fig.01

Check IC100(8) clock waveform

: See Fig.02

YES

Check Connector P101(3), P101(2),

P101(1) voltage : -28, -24, -21.5V

Does the signal #3 operate normally?

Check IC100(42) clock waveform

: See Fig.03

YES

END

START

Is the IC 5V power

supplied normally?

YES

Check IC100(13), IC100(43), IR100(2)

voltage : 5V

Legend : IC100(5)

IC number

IC pin number

3-17

FIG.01 IC100 VFD Chip Clock (about 460KHz)

FIG.02 IC100 VFD Control Clock Signal

FIG.03 IC100 VFD Chip Grid1 Pulse

3-18

4. DVI Troubleshooting Flow

END

DVI cable is pulg in ?

DVI ICON display ?

480P picture right ?

START

YES

720P, 1080I picture right ?

YES

Connect DVI cable

(A)

Check IC404 pin57(IDCK+),pin2(DE), pin4(HSYNC),pin5(VSYNC) The IDCK_ clock shall be 27MHz. Refer to Fig.1

Check IC404 pin57(IDCK+),pin2(DE), pin4(HSYNC),pin5(VSYNC) The IDCK_ clock shall be 74.25MHz. Refer to Fig2, Fig3 and Fig4.

Fig.01 Fig.02 Fig.03

Fig.04

3-19

(A)

Color Space Switch is RGB side ?

IC404 pin 11 is high volt ?

The emitter of Q409 is high volt ?

Change Switch to RGB side

Change the DVI chip

Use another DVI cable

Turn on the receiver monitor.

YES

3-20

5. CPU Troubleshooting Flow

END

Is power supplied normally?

Is each clock OK?

Is each reset OK at the time of power-on reset?

Is each chip selection OK?

Is each I2C channel OK?

Start

(1) outline

Check Power : Refer to (A)

Check each clock : Refer to (B)

Check reset circuit : Refer to (C)

Check each chip selection : Refer to (D)

Check each I2C channel : Refer to (E)

YES

Is each interrupt signal OK?

Check each interrupt signal : Refer to (F)

Are messages output through RS-232C port on PC terminal?

Check RS-232C circuit : Refer to (G)

YES

3-21

(A)

Is 2.5V supplied to L101 and 3.3V to L102?

Is 3.3V supplied to the pin 47 of IC104, IC105, the pin 1 of IC 102, 103, and the pin 51 of IC201?

Power Supply Check IC904 : 2.5V IC902 : 3.3V

Power Supply Check IC902 : 3.3V

YES

Check IC101, 102, 103, 104, 105

3-22

(B)

Is 25MHz clock output from the pin 3 of X101? Fig01

Is 37.5MHz clock input into the pin 87 of IC201? Fig02

Check X100

Check IC101 & IC201

YES

Is 9.375MHz clock input into the pin 1 of IC202? Fig03

Check IC201 & IC202

Fig.01 Fig.02 Fig.03

3-23

(C)

Is the pin 3 of IC108 reset?

Are the pin 42, 57, 61, 81, 83, 94, 92, 97 of IC201 reset?

Are the pin 4 of IC106 reset? Fig04

IC108 Check

Check IC101 & 201

IC106 Check

YES

Fig.04

3-24

(D)

Is logic low pulse seen at R138?

Is logic low pulse seen at R142?

Is logic low pulse seen at R144?

Check IC101, 104, 105

Check IC101, IC701

Check IC101, IC500

YES

Is logic low pulse seen at R143?

Check IC101, IC201

YES

Is logic low pulse seen at R108?

Check IC101, IC102

Is logic low pulse seen at R141? Fig05

YES

Check IC105, IC205, IC206, IC207

Is logic low pulse seen at R140?

Check IC101, IC1950

YES

Fig.05

3-25

(E)

Are IIC SCL and SDA signal input Into the pin 2, 5 of IC209 from IC101?

Check IC101, IC209

YES

Are IIC SCL and SDA signal output from the pin 4, 6 of IC209?

YES

Check IC209

Are the IIC SCL and SDA signal output from the pin of IC202? Fig06 & Fig07

Check IC202

Fig.06 Fig.07

3-26

(F)

Is logic low pulse output into the pin 31 of IC100?

Is logic low pulse output into the pin 57 of IC701? Fig08

Check IC100, IC500

Check IC100, IC701

YES

Is logic low pulse output into the pin 75 of IC1950?

Check IC100

Fig.08

3-27

YES

(G)

Is the pin 11 of IC204 OK? (TxD signal) Fig09

Is the pin 12 of IC204 OK? (RxD signal) Fig10

Check IC101, IC204

Is the RS-232C port setup is OK? (Baudrate, Parity, Data Bit, Stop Bit)

Modify RS-232C port setup

YES

Fig.09 Fig.10

3-28

6. VIDEO Troubleshooting Flow

End

No HV sync OUT?

Any problem in OSD ?

Any problem in main picture?

Start

YES

Is there any problem in AV out?

(A)

(B)

(C1)(D)

What is the main picture source?

DTV or NTSC.

(C2)

DTV

NTSC

3-29

(A)

Is power supplied to IC500?

Chage CSC switch to RGB mode

and check HV sync.

Is there any problem ?

Is VDP clock(IC602 pin28) supplied

to HD1? FIG.01

Check L500( 2.5V) L501(3.3V)

If HV sync exist in IC613 pin6,7

( FIG.03)(FIG.04)

then check IC613 pin1 is low.

If not, check IC201 pin45.

Check IC601 pin5 and IC612 pin4

in SD and HD respectively.

YES

Check IC601 pin1 and IC612 pin1 if there exist 27MHz clock. FIG.02

Fig.01 Fig.02 Fig.03

Fig.04

3-30

(B)

Check analog mute ON?

Check analog buffers.

IC610,IC609 for 480i,

IC607 for component YPbPr,

IC608 for RGB analog

YES

No OSD is not a problem.

Check DVI output.

Check A9V is supplied.

Jump to (A) flow

+ 90 hidden pages

Zenith HD SAT520 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual