Toshiba 32HFX72 General Adjustments Safety Instructions, RAY Radiation Precaution, AC Voltmeter

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CHAPTER 1 GENERAL ADJUSTMENTS

SAFETY INSTRUCTIONS

WARNING: BEFORE SERVICING THIS CHASSIS, READ THE “X-RAY RADIATION PRECAUTION”, “SAFETY PRECAU- TION” AND “PRODUCT SAFETY NOTICE” INSTRUCTIONS BELOW.

X-RAY RADIATION PRECAUTION

ADJUSTMENTS

1.Excessive high voltage can produce potentially hazard- ous X-RAY RADIATION. To avoid such hazards, the high voltage must not be above the specified limit. The nominal value of the high voltage of this receiver is (A) kV at zero beam current (minimum brightness) under a 120V AC power source. The high voltage must not, under any cir- cumstances, exceed (B) kV.

Refer to table-1 for high voltage (A), (B).

(See SETTING & ADJUSTING DATA on page 14)

Each time a receiver requires servicing, the high voltage should be checked following the HIGH VOLTAGE CHECK procedure in this manual. It is recommended that the read- ing of the high voltage be recorded as a part of the service record. It is important to use an accurate and reliable high voltage meter.

2.This receiver is equipped with a Fail Safe (FS) circuit which prevents the receiver from producing an excessively high voltage even if the B+ voltage increases abnormally. Each time the receiver is serviced, the FS circuit must be checked to determine that the circuit is properly functioning, follow- ing the FS CIRCUIT CHECK procedure in this manual.

3.The only source of X-RAY RADIATION in this TV receiver is the picture tube. For continued X-RAY RADIATION pro- tection, the replacement tube must be exactly the same type tube as specified in the parts list.

4.Some part in this receiver have special safety-related char- acteristics for X-RAY RADIATION protection. For contin- ued safety, parts replacement should be undertaken only after referring to the PRODUCT SAFETY NOTICE below.

INFORMATIONS GENERAL

SAFETY PRECAUTION

WARNING : Service should not be attempted by anyone unfa- miliar with the necessary precautions on this receiver. The fol- lowing are the necessary precautions to be observed before servicing this chassis.

1.An isolation Transformer should be connected in the power line between the receiver and the AC line before any serv- ice is performed on the receiver.

2.Always discharge the picture tube anode to the CRT con- ductive coating before handling the picture tube. The pic- ture tube is highly evacuated and if broken, glass frag- ments will be violently expelled. Use shatter proof gog- gles and keep picture tube away from the unprotected body while handling.

3.When replacing a chassis in the cabinet, always be cer- tain that all the protective devices are put back in place, such as; non-metallic control knobs, insulating covers, shields, isolation resistor-capacitor network etc.

4.Before returning the set to the customer, always perform an AC leakage current check on the exposed metallic parts of the cabinet, such as antennas, terminals, screwheads, metal overlays, control shafts etc. to be sure the set is safe to operate without danger of electrical shock. Plug the AC line cord directly into a 120V AC outlet (do not use a line isolation transformer during this check). Use an AC voltmeter having 5000 ohms per volt or more sensitivity in the following manner:

Connect a 1500 ohm 10 watt resistor, paralleled by a 0.15 F, AC type capacitor, between a known good earth ground (water pipe, conduit, etc.) and the exposed metallic parts, one at a time. Measure the AC voltage across the combi- nation of 1500 ohm resistor and 0.15 F capacitor. Re- verse the AC plug at the AC outlet and repeat AC voltage measurements for each exposed metallic part. Voltage measured must not exceed 0.3 volts rms. This corresponds to 0.2 milliamp. AC. Any value exceeding this limit consti- tutes a potential shock hazard and must be corrected im- mediately.

AC VOLTMETER

 

 

 

 

 

 

0.15F

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Place this probe on

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Good earth ground

 

 

 

each exposed

such as a water

 

 

 

metallic part.

pipe, conduit, etc.

1500 ohm

 

 

 

 

 

 

 

 

 

 

 

 

10 watt

SPECIFIC

PRODUCT SAFETY NOTICE

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These characteristics are often passed unnoticed by a visual inspection and the protection afforded by them cannot necessarily be obtained by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety charac- teristics are identified in this manual and its supplements; electrical components having such features are identified by the international hazard symbols on the schematic diagram and the parts list.

Before replacing any of these components, read the parts list in this manual carefully. The use of substitute replacement parts which do not have the same safety characteristics as specified in the parts list may create shock, fire, X-ray radiation or other hazards.

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Contents 32HF72, 32HFX72 Toshiba Corporation 36HFX72, 36HF72 Table of Contents RAY Radiation Precaution General Adjustments Safety InstructionsSafety Precaution Product Safety NoticeColor Purity Adjustment SET-UP AdjustmentDeflection Yoke PURITY/ Conv Magnet Rubber WedgesBLU RED RED/BLUE GRN Convergence Adjustments Center Convergence AdjustmentGRN SCREEN-CORNER ConvergenceConvergence Adjustments SET-UP Adjustment for Flat TubeColor Purity Adustment Center ConvergenceInformations Circumference ConvergenceEntering to Service Mode Service ModeDisplaying the Adjustment Menu KEY Function in the Service ModeAdjusting the Data Selecting the Adjusting ItemsExit from Service Mode Test Signal SelectionSelf Check Self Diagnostic FunctionBUS Line OK BUS Cont OK SyncAdjustment Procedure Electrical AdjustmentsPara Parabola DPCHorizontal Position HposHigh Voltage Check Circuit ChecksFS Circuit Check YESSafety Instructions Specific Informations Setting & Adjusting DataService Mode Adjusting Items and Datas in the Service Mode Option Progressive 43 DVLocation of Controls Representatives 36HFX72 Remote Control TV/CABLE function Programming Channel MemoryOMF Chassis and Cabinet Replacement Parts ListELECTROLYTIC, 16V 22UF M 3A ELECTROLYTIC, 160V 330UF M 3D Plastic FILM, 50V 0.01MF J Resistors CHIP, Metal FILM, 1/20W 7.5K OHM J Carbon FILM, 1/6W 75 OHM J Carbon FILM, 1/6W 820 OHM J Carbon FILM, 1/6W 1M OHM J 36HFX72 Coils & Transformers Semiconductors IC, PQ30RV1 DIODE, EU2A Miscellaneous Picture Tube Bottom Foil Side Signal Board PD0650POWER/DEF Board PD0159 CRT-D/VM Board PD0164 LOW B Board PB9567 AC in Board PD0161CONTROL-1 Board PD0651 CONTROL-2 Board PD0652 WOW Board PD0645 Terminal View of Transistors Schematic Diagram Structure Signalunit DiagramPower Consumption Power SourceAudio Power DimensionsToshiba Corporation Schematic Diagram Diagram Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page