AV-28BK5ECB AV-28BK5ECS SERVICE MANUAL COLOUR TELEVISION AV-28BK5ECB AV-28BK5ECS BASS BASS P. MODE . MODE / OK MENU MENU RM-C80 SPECIFICATIONS: Power source AC 220~240V 50Hz Sound output (watts) Rated Power output :5.0 x 2 Power consumption(watts) Maximum : 155 Picture tubes (cm)
AV-28BK5ECB AV-28BK5ECS CHASSIS DESCRIPTION [Chassis Block Diagrams] This is a basic diagram for all models and therefore differs slightly from the actual block diagram. Outline Fig.-1 No. 51758...
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AV-28BK5ECB AV-28BK5ECS CHASSIS DESCRIPTION Video signal rooting IF Stage IC101 IC241 IC351 IF/VIDEO/ SHARPNESS MATRIX CHROMA <TDA9178> <TDA9330H> <TDA9321H> SAW Filter IC731 R-VIDEO OUT <TDA6101Q> Y, U, V 2(Y, U, V) DIGITAL SCAN IC721 CONVERTER G-VIDEO OUT H-Sync CIRCUIT <TDA6101Q>...
AV-28BK5ECB AV-28BK5ECS CHASSIS DESCRIPTION System control RL649 Q649 Power CVBS input Supply Power ON/OFF Circuit 60 48 49 44-47 43 Key SW Input IC871 IC801 Power Failuer Detect RC Pre-amp. AV1 SW in AV2 SW in AV3 SW in I2C BUS Fig.-4...
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AV-28BK5ECB AV-28BK5ECS CHASSIS DESCRIPTION [Digital Scan Operation] 100Hz Digital Scan Converter circuit 100Hz converter circuit consists of the following ICs. - TC90A36F, IC7201 Field Progressive Converter - MSM518221A, IC7202, IC7203 Video Memory - TLC2932I, IC7204, IC7205 PLL (Phase Locked Loop)
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AV-28BK5ECB AV-28BK5ECS CHASSIS DESCRIPTION 50Hz 100Hz A' = A, B'= B (b) Double Scan (a) Normal Scan Fig.-7 The U/V-signals are converted in progressive at multiplexer and converted from A to D in 8 bit, and then applied from pins 34 to 41 of IC7201 to pins 1 to 40 and 24 to 27 of IC7203 <MSM518221A>, video memory, for writing.
AV-28BK5ECB AV-28BK5ECS OPTION SETTINGS This TV set allows to set up the following option settings. PROHIBITION Prohibit the presetting and sets the current volume as the maximum volume level. PROHIBITION OFF or START POSITION Presets the programme position when the set is switched on.
AV-28BK5ECB AV-28BK5ECS SERVICE ADJUSTMENTS [After replacing the Menory IC (IC802)] The memory IC, IC802, stores the feature setting data of TV set and service adjustments data for each circuit, therefore, when the memory IC is replaced, it should be performed by following “FEATURE SETTING” and “ADJUSTMENT”.
AV-28BK5ECB AV-28BK5ECS SERVICE ADJUSTMENTS [ADJUSTMENT MODE] Note: Some items of the service adjustments for this chassis are controlled by the CPU, IC801, and the adjustments are carried out by using the RC handset. IMPORTANT NOTICE Do not attempt to adjust service adjustments not listed on the above otherwise it may cause loss of performance and product safety.
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AV-28BK5ECB AV-28BK5ECS SERVICE ADJUSTMENTS [ADJUSTABLE SERVICE ADJUSTMENT] IMPORTANT NOTICE Do not attempt to change the data value of service items not listed below table otherwise it may cause loss of performance and product safety. If you can not restore the data value of each service item, please initialize the memory IC following to the below description “INITIALIZATION OF MEMORY IC”...
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AV-28BK5ECB AV-28BK5ECS SERVICE ADJUSTMENTS [ADJUSTMENT] How to adjust the each service data, please see “ADJUSTMENT MODE” on page 13 for entering the service mode , selecting service item and adjusting the service data value. IMPORTANT NOTICE Do not attempt to adjust the following service adjustments except requiring the readjustments in servicing otherwise it may cause loss of performance and product safety.
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AV-28BK5ECB AV-28BK5ECS SERVICE ADJUSTMENTS VERTICAL ADJUSTMENT PINCUSHION ADJUSTMENT VERTICAL CENTRING ADJUSTMENT 1. Receive circle (or cross-hatch) pattern. 1. Receive circular pattern. 2. Enter to the service mode and select mode “SHAPE”, 2. Enter to the service mode and select mode “SHAPE, item “SHAPE 4.EWP”.
AV-28BK5ECB AV-28BK5ECS CPU PORT FUNCTIONS Pin No. Function Name Function IN/OUT MMU0 MMU3 ADDR10 Address bus 10 ADDR11 Address bus 11 ADDR9 Address bus 9 ADDR8 Address bus 8 OSC-IN Clock Input OSC-OUT Clock Output ADDR13 Address bus 13 ADDR14...
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AV-28BK5ECB AV-28BK5ECS Pin No. Function Name Function IN/OUT WSCF VDD-A PXFM RESET Reset Input MCFM JTRSTO TXCF CVBS0 TEST0 CVBS1 CVBS2 GND-A DAT3 Data bus 3 DAT4 Data bus 4 DAT5 Data bus 5 DAT6 Data bus 6 DAT7 Data bus 7...
AV-28BK5ECB AV-28BK5ECS IC BLOCK DIAGRAMS IC001 TDA7263M <Audio Output> CF COUPL RF1 27K IN -L OUT L IN +L MUTE PROTECTION REFERENCES TURN-ON SUPPLY AND-OFF PROTECTION VOLTAGE IN +R OUT R IN -R TDA7263M RF1 27K CF COUPL IC101 TDA9321H <IIC bus controlled TV input processor>...
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