Sanyo AC1-C, Training Manual

Page 1: ...COLOUR TELEVISION TRAINING MANUAL I FILE NO c Ps60 uo Chassis Series ACI A ACI B ACI C CIRCUIT DESCRIPTION BLOCK DIAGRAM OF S TROUBLE SHOOTING I REFERENCE NO T1520009 ...

Page 2: ...roma stage 2l 3 3 Deflection Stage 2l System Switches 22 23 4 1 Sound Carrier Trap 22 4 2 SIFFiltering 23 Audio Output 24 Vertical Output 25 Horizontal Output 26 Power Consumption Saving Circuit 27 Part 2 Block Diagram of K LA7687 cl F Video Chroma Deflection 28 LC89950 1 H Delay line 29 LA7642 SECAM Decoder 29 LA7837 cVertical Output 30 LA4285 LA4287 cAudio Output 30 Part 3 Trouble Shooting Chart...

Page 3: ...m control circuit for AC1 C chassis LA7687 IC201 for the IF video chroma de modulation and deflection circuit L LC89950 IC271 for the 1H delay line circuit LA7642 IC280 for the SECAM decoder circuit LA7837 IC501 for the vertical deflection output circuit LA4287 ICOO1 for the audio output circuit for AC1 B chassis LA4285 ICOO1 for the audio output circuit for AC1 A and AC1 C chassis ST24C02AB etc I...

Page 4: ...llowing figure shows a block diagram of the CPU peripheral circuit Ii L I 2 C 3 c o E o T Ml II Oalm Zz t C JOIN i il i u N i l f lr I cum I m 3 2 c ml r G x II ii ii ii ii J di n Ce a r JI u L _ _ L J 4 Training Manual ACl Chassis ...

Page 5: ...tage output 38 Band switch output 3 UHF 9 GND Digital 39 Volume control output 10 Oscillator input for CPU 40 TV AV switch output TV Low 11 Oscillator output for CPU 41 Power error detection input 12 5 power supply Digital 42 Sync identification input No sync Hi 13 AFT S signal input 43 Colour killer input 14 Key scan input DC 2 44 RC signal input 15 Key scan input DC 1 45 SECAM killer input 16 Op...

Page 6: ...U 15 14 L 3 K1 5 j 27k K2 27k 10k 3 W 10k 5 6k KJ 5 6k 3 9k K 3 9k 2 2k K 3 2 2k 2 7k K7 K 4 2 7k 0 27k 0 27k lrwut voltaqe to pin 15 7 Intro It vnltarie to nin 14 1 Ke K1 K2 K3 K4 K5 K6 K7 OFF Range of voltage 0 5V 1 1 V l l V 1 7V 1 7V 2 3V 2 3V 3 OV 3 OU 3 6V 3 6V 4 2V more than 4 2V Less than 0 5V Function Position Up Postion Up Position Down Level Up Level Down Undefined Undefined No Key pres...

Page 7: ...pe of tuner pin 5 pin 5 pin 5 No s of positions pins 6 48 nfa nla No s of positions AV modes nla nla pins 6 48 RC status pin 7 nla nla Blue back in TV mode nla pin 6 nla Colour system pin 16 pin 16 pin16 SIF system pins 49 52 pins 49 52 pins 49 52 n a not available Inhibit function AC1 A chassis Buss CPU 10 1 9 expander function AC1 B and AC1 C IN SW Specification off w o Inhibit function on w Inh...

Page 8: ... 10k 10k POS2 Sw poa Remote control status AC1 A chassis CPU Rx 7 9 Blue Back function in TV mode AC1 B chassis CPU Posl Sw off on off on on off off Specification 60 programme positions 1 AV mode 100 programme positions 1 AV mode 100 programme positions 2 AV modes 100 programme positions 2 AV modes RC SW Specification off w o remote control function on w remote control function BL SW I Specificati...

Page 9: ...stem 0 78V I 41V 33k VMT system O 15V O 78V 10Ok PAL system less O 15V Open PAL system When the supply voltage is 5 OV I J7 11 sw BG SW I sw DK SW Specification off off off off Multi system off off on off Px off off on on Indonesia 1 on off off off 3 system ACI A on off on off East Europe off on off off China 1 off on on off China 2 on on off off China 3 ACI A off in on on Indonesia 2 on on on on ...

Page 10: ...4 to turn off 24V supply for ver tical and horizontal output circuit 7 8V supply for lF Video Chroma circuit and 12V for tuner circuit are all cut off resulting in the TV set going into the stand by mode When the TV is switched back into the power on mode Q683 and Q684 are turned on and the relevant voltages are supplied back to each circuit Q683 mmmmmmm mmm mm supply R681 15k 7 AAA 7 5v Power On ...

Page 11: ...s causing the power oscillation to stop If one of the above diodes is turned on the voltage of Q631 emitter decreases and it turns on completely Photo coupler D615 is driven by this and generates a current which drives Q612 on As a result the operation of the power oscillation circuit is stopped Under normal circumstances these parts D615 Q631 D641 R635 R636 VR631 are operating as the error detect...

Page 12: ...f these transistors then supplies the drive voltage l 2V to the tuner according to the output signal from the CPU as shown below table Antenna I _ Tuner VL VH u Cllo3 12k Q104 12k Q105 R898 12k Band Switching Logic output Pin36 Pin 37 Pin 38 Q103 Q104 Q105 Selected Band LH H on off off VHF Low HL H off on off VHF High HHL off off on UHF 36 VL 37 VH 38 UHF CPU 12 Tmining Manual AC1 Chassis ...

Page 13: ...e along with table 2a until the AFT voltage reaches less than 1 5V Go to next step Decrease the tuning voltage along with table 2b until the AFT voltage reaches more than 2 OV Go to next step The CPU judges that the sync signal is existing or not by detecting the voltage on pin 46 If the CPU detects a low voltage on pin 46 go to step 2 If the CPU detects a high 5V voltage on pin 46 complete the di...

Page 14: ...ignal Pin 13 AFT S Curve of IC801 Input Pin 8 of IC801 Pin 46 of IC801 Tuning Voltage 3 5V 3 OV 2 OV A IF Ident Signal Input Tuned point Input Voltage Level of Pin 13 Judgement LL OV 1 5V Tuning Voltage Down L 1 5V 2 OV Tuning Voltage Down M 2 O 3 OV Tuned Centre H 3 OV 3 5V Tuning Voltage Up HH 3 5V 5V Tuning Voltage Up 14 Training Manual AC 1 Chassis ...

Page 15: ...ghtness contrast tint and sharpness for picture controls and selection of crystal control are controlled via the analogue bus lines connected from pins 23 and 24 of the CPU to pins 18 and 19 of IC201 LA7687 The CPU outputs the data and L address signals during a vertical retracing period and the control address and data of crys tal are represented in 8 bits and data of picture controls are represe...

Page 16: ... Control Item Specification of Reference output LA7687 voltage of CPU PAL4 43 I O 1 48V 0 04V 02 255 PAL3 58 1 70V 2 70V NTSC3 58 2 90V 3 90V NTSC4 43 4 1 Ov 5 00V 2 20V 112 255 3 22V 164 255 5 00V 255 255 b Picture control 7 bits l 27 steps Control Item Reference output voltage of CPU Minimum I Maxmum Brightness Contrast Colour Sharpness Tint 0 43V 11 127 2 48V 63 1 27 Ov 0 1 27 0 95V 24 1 27 1 2...

Page 17: ...NTSC I 2 7 3 6 I HzH It dependsonreceiving TV system HZ High impedance SIF system switching output 1 Multi system SIF system r Auto 5 5 MHZ 6 OMHZ 6 5MHz 4 5MHZ Output pins Display 52 51 50 49 HHH S1 LHLL S2 LLHL S3 LLLH S4 HLLL S5 The output level of pin 52 in the AUTO mode is determined by the followingcondition AUTO BAN 50 L TV AUTO B W H PAL 50 or 60 L SECAM 500r60 L NTSC4 43 50 or 60 L NTSC 5...

Page 18: ... system SIF system Output pins Display 52 51 50 49 LLLL No Display 7 China a svstem S1F system Output pins Display 52 51 50 49 Auto LHH S1 6 5MHz LLLH S2 6 OMHZ LLHL S3 4 5MHZ HLLL S4 8 China b system Samecondition withMultisystem SIF system I Output pins Display 52 51 50 49 Auto LLH S1 6 5MHz LLLH S2 4 5MHZ I HLLL I S3 I Same condition with Multi system 9 China c system SIF system Output pins Dis...

Page 19: ... the buffer and inverter circuit Q845 and Q837 The horizontal pulse is supplied from pin 4 of the flyback transformer through the inverter circuit Q836 If one of these pulses is not supplied to the CPU the on screen display cannot be dis played CPU H SYNC 2f V SYNC 2 Ul_bv 5VR883 Horiz 3 3k JL l l Hnriz I I Vert u u Vert I T471 FBT IC201 lF Video Chroma 20 V DRIVE V Dfive pulse to V OUTPUT IC Trai...

Page 20: ...d peripheral resistors and it is output as a composite video signal at pin 8 This composite video signal passes through the 6 0MHZ l 6 5MHz D K and 4 5 MHz M sound bandpass filtering circuit and it is input into pin 1 of IC201 In the IC this sound IF signal passes through the SIF amplifier FM detector and audio output circuit and it is then output from pin 51 as audio drive signal IC201 X161 lF VI...

Page 21: ...ed in the selection circuit driven by the blanking signal input to pin 28 and finally output to pins 33 34 and 35 The Y luminance signal is output from pin 32 The colour saturation contrast brightness tint and sharpness controls can be controlled by the CPU in 7 bits digital data through the analogue bus lines on pins 18 and 19 3 3 Deflection stage The horizontal oscillator circuit provides a 500k...

Page 22: ...of IC201 When other systems are selected the compos ite video signal is fed through the 5 5 MHz 6 OMHz trap Xl 82 or the 6 5 MHz trap Xl 83 which remove the respective intercarrier sound contents The remaining video is fed to pin 10 of IC201 via QI 83 This switching is shown in the table below 10 IC201 lF Video chrome 8 CPU 34 4 5 MHZ Sw Video in C21O 1 r L181 I R196 220 i Video out Q184 R184 680 ...

Page 23: ...s then fed via the relevant bufferQ134 4 5MHz Q133 5 5MHz Q132 6 OMHZ Q131 6 5MHz to the SIF input pin 1 of IC201 for de modulation IC201 lfNideo chroma 8 SIF Input 1 52 CPU 5C 51 49 Video Sound Carrier Output h Sound Carrier 4 Q184 SIF Filterina Circuit SIF Svstem Auto 5 5 MHZ 6 OMHZ 6 5 MHz 4 5MHZ 1 Q136 Q134 X134 4 5 MHZ F II 11 11 T T J J Q133 p J II q r X133 Q135 5 5MHZ J Q132 II 4 q J X132 6...

Page 24: ...es through the pre amplifier circuit and the drive circuit into the audio amplifier The sound volume control is supplied from pin 39 of the CPU to pin 5 of ICOO1 through the digital analogue converter circuit The audio amplifier is the SEPP Single Ended Push Pull type and the output from pin 9 drives the speaker directly IC201 lF VIDEO CHROMA b Q184 8 SOUND FILTERING E CIRCUIT SIF Carrier 1 3 n F ...

Page 25: ...canning period the current path is C515 DY pin 12 pin ll GND R518 In this way an increasing sawtooth waveform current flows directly to the DY to perform electron beam deflection During the first half of the blanking period the vertical ramp signal suddenly turns off Since there is no longer any current flowing into the DY the magnetic field collapses causing an induced current to flow as flows DY...

Page 26: ...ored in C435 then flows back to the DY causing an opposite magnetic field to be stored in the DY This field then collapses increasing a current which switches the dumper diode in Q432 ON The resonance state is completed and an increasing current then flows again directly to the DY through the dumper diode By this means the deflection in the first half of the scanning period is performed When Q432 ...

Page 27: ...tor in D61 5 is completely turned on then Q612 is turned on and Q613 is turned off By this means the oscillation of power circuit stops and the voltage of secondary power supply falls down Also the voltage of point A falls down from 15V gradually When the voltage on Q685 base is less than voltage of Q685 emitter Q685 is turned off and then Q686 is off then D615 and Q612 are turned off Finally Q613...

Page 28: ... 5MHZ 1 ID OUT M r An OUT SOUN TRAP a w l 3 3 ID 9 5MHZ T s VIDEOOUT a I l bWFIN Al s l l l A H tJ3 58MHz 5 ACL i i J S SW c 3 II J S CHROMA c I 1 EXT VIDEOO z Vcc 5V o ABL O KILLER BUS 1 G HI J BUS20 z 4 IIJ g V OUTO if GND II 11 1 1 I 1112 1 I I 1 1 1 N 50160HzO L d u I 28 Tmining Manual AC1 Chassis ...

Page 29: ... 9 10 11 12 m g 2 m 3 C1 m c 3 0 I u II u k s J c1 VCC2 3 1 H Delay Line LC89950 I Vss B Y IN Vdd R Y IN 4MHZ OUT COMP 4BGP LC89950 14 5 CLAMP CCD I 1OUTPUT 3 254 5bii S G AMP A I I A 01 02 n 4 LEVEL AUTO BIAS INCREASER CLAMP CCD OUTPUT 1 254 5bit S G AMP t BGP 8 CLOCK DRIVER L 4 1A 4 BGP c BGP 13 DETECTOR 12 OUT I OUT PIN Training Manual AC 1Chsssis VCO IN 29 PC OUT ...

Page 30: ...T T ACC SW3 SYSTEM 1 SN2 PULSE DET 1 I I I I I I t BELIJEQU BELIJEQU Swl LIM ADJ FILTER 4 LA7642 i KILLER PLL DET Vco CLAMP 1 m i ID KIL ID I FIL 1 2 3 4 5 6 7 1 I LI I 5 Audio Output LA4285 LA4287 LA4285 4 I p cc 4 I GND NF I I GND 7 6 5 4 3 2 1 Vcc _ INT AUDIO IN VOLUME k EXT AUDIOIN Di CONTROL SPL4KER lNT EXT SW 7 7 30 Training Manual AC I Chassis ...

Page 31: ...MEMO 31 Training Manual AC Chassis ...

Page 32: ...s AC1 I I Dead age 1 I 1 No picture No sound Page 36 37 No picture sound OK Page 38 I I I No sound picture OK age I I I No colour Page 40 Incorrect colour phase w Page 41 No vertical deflection Page 42 No on screen display Page 43 32 Training Manual AC 1 Chassis ...

Page 33: ...0V Check voltage on pin 1 of IC651 15V AC cord SW601 F601 L601 R602 Q611 Q612 Q613 C617 R620 R621 R622 D625 C616 R624 D634 C644 C643 C645 D641 ICOO1 CO07 T611 L603 L606 Q686 Q685 D685 t No 1 3651 C651 IC801 IC802 Is the power LED lighting C815 C816 C801 C828 C81O I I Yes I C809 I Check voltage 24V on Q683 Ov D633 R643 emitter 1 24V v Check voltage l 30V on both Ov ends of C641 C641 D631 130V or mo...

Page 34: ...18 C515 C524 C517 C520 D507 DY 1 No t Ov Check voltage on pin 41 of IC801 R855 C855 IC801 and check error detection lines Check voltage 24V on Q683 col Ov Q683 R683 Q682 R681 Iector IC501 C521 24V v Check voltage l 5V on Q684 col Ov Iector Q684 R685 D683 15V Check voltage l 2V on Q652 Ov Short circuit on 12V line check emitter Q652 R652 R653 D652 C652 C654 C510 C106 C119 IC501 12V tuner Short c wi...

Page 35: ... waveform on Q431 collector D IC201 X361 R365 1 No Horiz output circuit Q432 C435 Is the CRT heater coil lighting R435 R442 L441 T471 T431 Check voltage on terminal KQS 1 I 180V Check voltage on both ends of C445 1 5 to 1OV Q449 R449 R446 R447 DY R451 C429 D491 C491 C445 D442 R448 Training Manual ACIChassis 35 ...

Page 36: ...4 Yes Q1 83 R196 sound trap circuit emitter w X181 X182 X183 D181 D184 R188 etc Is video signal observed on pin 8 of I Iiclrizl v I yes IC201 Q184 R197 1 r I L I No t Check voltage 33V on both ends Ov R816 D801 C829 of D801 33V Is tuning voltage changing on termi No nal TU on the tuner when tuning Yes OV to 33V r b 1 I Go to next page 1 I I Check tuning circuit IC801 Q813 R811 R81O C805 C806 R813 ...

Page 37: ...ltage on terminal O or 12V AGC on the tuner w C104 R164 R165 C108 C168 3V to 6V L Y Check aerial cable tuner and IF peripheral circuit IC201 Q1 01 X161 X171 C162 C197 OR Memorv circuit IC802 R801 R802 R807 R808 R867 R868 AFT circuit R177 C177 R176 R175 Video detection circuit X171 R174 C176 R173 R170 C175 C172 C178 Ident circuit to CPU C858 R858 R859 IC201 TV AV switch circuit R171 R815 IC801 L Tr...

Page 38: ...re sound OK F1 1 Horiz 8V Is Y signal observed on pin 32 of IC201 Is Y signal observed on Q261 emitter L731 C731 screen circuit T471 No El WI Holiz 8V No IC201 L241 C211 R211 R222 R224 C222 Q261 R232 R263 D232 Q252 Q251 D251 38 Training Manual AC Chassis ...

Page 39: ... of ICOO1 es Speakers headphone socket CO05 CO06 I I I 1 I No El m 0 5V Check waveform on pin 51 of es ICOO1 Q016 COO1 C016 C172 IC201 w R166 CO04 CO03 R016 No Check SIF filterincl circuit No sound on all of systems Check C171 R152 Q137 L132 R151 C147 peripheral circuit No sound on 6 5 MHz system Check Q1 35 Q1 31 R832 Xl 31 C131 peripheral circuit No sound on 6 OMHZ system Check QI 35 Q1 32 R833 ...

Page 40: ... colour on NTSC system No colour on PAL system X241 IC201 No colour on SECAM system es SECAM decoder peripheral cir cuit IC281 C281 C283 C884 I C285 C286 C287 C288 Q281 No colour on all of systems 1 v T471 R351 R352 R353 D352 R354 40 Training Manual AC Chassis ...

Page 41: ...VR712 Q711 VR712 VR711 R235 w R714 Excessive green colour Q721 R721 R722 C722 VR721 1 Loss or poor green colour Q721 VR721 R724 R233 L Excessive blue colour Q701 R701 A R702A VR701 w VR702 C702 1 Loss or poor blue colour Q701 VR701 VR702 R704 w R234 Incorrect colour phase D IC271 peripheral circuit C271 C273 C274 C237 C236 C278 C289 L 41 Training Manual ACIChassis ...

Page 42: ...ge on pin 13 of IC501 w L511 D512 Vert IV Check waveform on pin 6 of IC501 A IC501 IC201 C512 C513 D513 R512 C511 R511 SW191 Yes R513 C515 C518 R518 C524 DY Compressed or expanded vertical Q526 VR51 O R525 R514 screen size R515 R522 C514 R516 C513 R526 42 Training Manual AC1 Chassis ...

Page 43: ...ptom No on screen display IINo on screen display 11 ru Check waveform on pin 26 of IC801 1 Yes 1 I Veft 5V Check waveform on pin 25 of 0 w Q837 R837 R838 C819 Q839 IC801 R846 Q845 I Yes IC801 C812 C813 L804 R228 43 Training ManualACIChessis ...

Page 44: ...TRAINING MANUAL AC1 Al 4800 Jun 96 500 Sl s ifgwwo SANYO Electric Co Ltd Training Manual ACI Chassis ...