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WorldRadioHistory

Содержание Proscan LaserDisc PSLD40

Страница 1: ...PRoScAN RCA LASER si TechnicalTraining Manual THOMSON CONSUMER ELECTRONICS INC TECHNICAL TRAINING P O BOX 1976 INDIANAPOLIS IN 46206 WorldRadioHistory...

Страница 2: ...D o o WorldRadioHistory...

Страница 3: ...Data All product safety requirements and testing must be completed prior to returning the instrument to the consumer Servicers who defeat safety features or fail to perform safety checks may be liable...

Страница 4: ...Processing 21 Overview PSLD40 23 Mechanism 23 System Control 25 Servo 26 Signal circuits 27 Service Procedures 28 System Control 29 LDR300 29 PSLD40 30 Servo Section 34 Focus Servo 34 Height Servo 38...

Страница 5: ...ndix C Laser Lens Cleaning 60 Appendix D IC201 Digital Audio Decoder 61 Appendix E ICI 1 Mode Control Microprocessor 63 Appendix F IC801 Mechanical Control Microprocessor 64 Appendix G IC601 Servo Con...

Страница 6: ...WorldRadioHistory...

Страница 7: ...r that point and resumes normal play back from that point forward Memory Repeat On the operator s command memorizes alocation on a disc The player will then search for that point and resume playback S...

Страница 8: ...rom the optics reducing the amount of laser light entering the 1 4 WAVELENGTH LASER optics The laser light that is not reflected away from the optics is canceled by the laser light being transmitted b...

Страница 9: ...modu lated signals for recording on the disc quip The frequency spectrum for the different signals rec orded on avideo disc is shown in fig 5 The video infor mation is FM modulated with acenter frequ...

Страница 10: ...2 13 14 VIDEO SIGNAL VIDEO MODULATOR Fig 5 Frequency Spectrum of LD Player L AUDIO J L CHANNEL I MODULATOR R AUDIO J R CHANNEL 1 MODULATOR DIGITAL RIGHT CHANNEL DIGITAL LEFT CHANNEL DIGITAL AUDIO PROC...

Страница 11: ...caused by the laser exposure The disc then has a SPEED 1800 RPM VERTICAL BLANKING INTERVAL VER11CAL BLANKING INTERVAL CAV DISC ROTATION layer of nickel deposited on it to make the master disc The mas...

Страница 12: ...format CLV formatted discs can store up to 1 hour of video per side This allows complete films to be stored on one disc The disadvantage of CLV formatted discs is that special effects cannot be easily...

Страница 13: ...NNEL AUDIO LEFT CHANNEL AUDIO LPF AID CONVERTER D CONVERTER MULTIPLEXER STAGE 1 Digital Audio In the video disc format the digital audio is processed in the same manor as the digital audio recorded on...

Страница 14: ...Bursts errors are groups of missing data usually caused by scratches or finger prints on the disc surface To prevent this type of error from making the disc unplayable adjoining bits of data are separ...

Страница 15: ...s made up of 588 bits this includes the sync and the control data The disc shown in fig 10 is aexample of the format of acompact disc In the compact disc format the speed varies from 500 RPM on the in...

Страница 16: ...ore correction range The slider servo also moves the pickup assembly forward and back ward during the search and scan modes This command comes from the system control through the tracking servo R IN L...

Страница 17: ...l The system control then starts the spin dle motor rotating and allows the tracking servo to lock onto the track of data During the time the spindle motor is rotating FG pulses are monitored When the...

Страница 18: ...h a POWER PVCKUP SUPPLY ASSEMBLY LDR300 Service Position VIDEO SERVO PROCESSOR 111 lllll DIGITAL AUDIO Fig 12 LDR 300 ANALOG AUDIO FRONT PANEL 16 WorldRadioHistory...

Страница 19: ...0 uses one motor to per form 3functions These functions are I Move the disc tray in and out to let the operator a place adisc onto the tray 2 Once the tray is moved back into the machine the tray is l...

Страница 20: ...nical control microprocessor then starts the spindle motor rotating to its predetermined speed This speed is monitored by the FG pulses sent to the mechanical control microprocessor The micro not only...

Страница 21: ...ical electrical converter IC The outputs from the sensors are then applied to different inputs of acomparator If the beams 3 DISC IS TOO FAR ERROR VOLTAGE NEGATIVE v deviate to the right side of the r...

Страница 22: ...This is one of the error signals used by the TBC servo to provide time base correction The other error signal is generated by LEFT RIGHT 0 1 ERROR VOLTAGE POSITNE O comparing the chroma burst signal...

Страница 23: ...it After demodulation the video signal goes through drop out compensation time base error compensation and chroma phase compensation After compensation the video signal is sent to the OSD On Screen Di...

Страница 24: ...CLAMPER ASSEMBLY 22 POWER SUPPLY PSLD40 Service Position ALPHA TURN ASSEMBLY SERVO Fig 16 PSLD40 VIDIE AUDIO PROCESSING BOARD FRONT PANEL WorldRadioHistory...

Страница 25: ...removing the disc from the player Like the LDR300 the PSLD40 can be divided into four circuit areas mechanism system control servo and sig nal processing Mechanism The alpha turn mechanism is the main...

Страница 26: ...attempted on side B This step is to re clamp the disc onto the spindle motor The reason for reclamping is PICKUP ASSEMBLY that in the manufacturing of alaser disc each side of the disc is made separat...

Страница 27: ...a turn mechanism 180 After adisc is loaded and clamped onto the spindle motor the mechanical control microprocessor enables the height servo This is done to move the pickup assem bly within the operat...

Страница 28: ...now inverted the motor is rotated in the opposite direction As in side A playback after the spindle motor reaches its predetermined speed the tracking servo loop is closed and normal playback is resum...

Страница 29: ...wer travel of the laser assembly A separate motor is used to drive the height mechanism in the pickup assembly The tilt servo in the PSLD40 is different than the LDR300 because of the alpha turn mecha...

Страница 30: ...layer loads and plays adisc normally and then starts to skip A Check the operation of servo section Pg 34 5 If the player goes into the play mode and does not produce apicture A Check the operation of...

Страница 31: ...LOADING TILT POSMON PICKUP POSMON 0 5V IC802 DRIVER SLOW SLO IC 801 PD0071 MECHCON wEIPARK2 4 1PARK I The shake line is pin 45 of IC11 and is the request for data from both microprocessors X SCK is pi...

Страница 32: ...tive action does not correct the problem or one of the steps in the start up sequence cannot be completed the mechanical control microprocessor then places the unit in the stop mode This can make trou...

Страница 33: ...n 12 of the mechan ical control microprocessor The mechanical control microprocessor then stops the slider motor and looks for afocus lock When afocus lock is achieved playback of side Bis started Aft...

Страница 34: ...n 30 3V P P 9MHz 1 If clock signal is not present suspect X801 and IC801 C If present check for data activity on the commu nication lines between the mechanical control microprocessor and the mode con...

Страница 35: ...FOCUS LOCK PO IN SUDER POSMON PIN 12 U DISC SENSE OV CD DISC SENSE 5 V SIDE A INSIDE 3 V SIDE B INSIDE 5 V PICKUP POSMON SWITCHES SIDE A INSIDE MODE PDB01 7 ICII CONTROL POWER ON TO P S RESET SWIKE S...

Страница 36: ...slider servo on Pg 41 C Suspect tilt servo on Pg 43 3 If the disc player advances the pickup across the disc looks similar to the disc player being in the scan mode A Suspect the tracking servo on Pg...

Страница 37: ...oil is also monitored to reduce the gain of IC 605 This prevents ahigh DC off set from destroying the focus coil The focus drive signal is also muted during reset of the microprocessors This protects...

Страница 38: ...k command is given to the mechanical control microprocessor This lock command is alow from IC601 pin 26 and keeps C643 from charging through D612 PICKUP ASSEMBLY eNle 82 F DIFFERENCE TP3 CN301 3 m ff...

Страница 39: ...5 1 5VDC 3 ukrirrTsER 400mVP P 10mSIDIV OFFSET F If the focus sum voltage goes over 4V DC with a oscilloscope monitor the DC level a pin 4 of IC601 focus error input When the pickup is searching for a...

Страница 40: ...ffset of the error signal during inverted operation of the pickup assembly side B playback This inversion of the DC offset reverses the direction of the height motor If this was not done the error sig...

Страница 41: ...1 is then applied to the CD and LD equalizers The laser disc player having already determined what type of disc is being played selects the correct input to be applied to the tracking loop If the trac...

Страница 42: ...ntarily opened and then closed This cycle of opening and closing the tracking loop is done as long as the player is scanning The scan command is sent to IC601 at pin 13 The polarity of the signal at p...

Страница 43: ...an disc as it spirals outward The slider servo monitors the DC level on the return line of the tracking coil and moves the laser assembly to minimize it This keeps the tracking servo within it s oper...

Страница 44: ...e input to the driver Pin 1is the non inverting input to IC603 so any signals applied to it will be the same polarity at the output When Q618 is turned on by the mechanical control microprocessor pin...

Страница 45: ...iving diode that is the closest to the disc will have alarger output than the diode that is farther from the disc The error signal from the diodes is added at IC601 pin 22 When the two diodes receive...

Страница 46: ...e to prevent the tilt sensor from transmit ting off the edge of the disc PICKUP ASSEMBLY SPINDLE MOTOR 44 DISK TILT MOTOR Fig 29 Tilt Servo PSLD40 TILT SENSOR IC1 01 AMP Service Procedure LDR300 To ch...

Страница 47: ...es not vary suspect the tilt sensor and IC601 B If the level does vary suspect IC801 PSLD40 1 To check the tilt servo in the PSLD40 in the play mode check the DC offset on IC601 pin 22 If the tilt ser...

Страница 48: ...illeilweA 70mV DRIVER Q112 0110 10mS DIV PRE DRIVER Q913 Q914 PRE DRIVER Q911 Q912 oscillator in IC901 14 31818MHz by 910 The phase difference between the horizontal sync pulses and the reference sign...

Страница 49: ...rol microprocessor switches the input of the phase comparator from the horizontal sync pulses to the 1 IC901 VARIABLE GAIN CONTROL FG sensor pulses When the spindle motor is at aprede termined speed t...

Страница 50: ...al at pins 6of IC901 This signal should be 5V P P with apulse width of approximately 50 1 If PWM signal is present troubleshoot spin dle motor drive circuitry Q913 Q914 Q111 and Q113 48 C If PWM signa...

Страница 51: ...IC903 IC903 INVERTER 7 8 3 2 10 R124 6 AMP DRIVER 1 01_ Q112 Q110 DRIVER 1 4_ Q Q111 113 01 PRE DRIVER Q911 Q912 SIDE A B PRE DRIVER Q913 Q914 C3 C REF GEN LAO IC905 0 PSLD40 Spindle Drive Repeated 5V...

Страница 52: ...mechanical control microprocessor Also at pin 34 the horizontal and vertical sync signals are separated and sent out on pins 35 and 36 In the second path the video signal is applied to pin 26 clamped...

Страница 53: ...5VP P 20 S P RF CONNECTION IC401 DEMOD mmunmi r 1 I II IC403 17 1_ VARIABLE CI IC404 q DELAY p LINE r PLI 17 L yo 27 PHIUPS DATA VPS ERROR Fig 32 Video VP P 11M ESASE ERROR 204 DIV 4 5VP P H SYNC SYN...

Страница 54: ...s the offset by automatically tracking the shifting DC baseline and can celling it out Without the ATC the process of con verting an RF signal to adigital signal would be less accurate Consequently th...

Страница 55: ...e 0 Hz 20KHz The output of the digital filter is right channel data pin 11 and left channel data pin 12 The right and left channel data is applied to IC203 the 1 bit digital to analog converter DAC In...

Страница 56: ...rop 4mVP P 10mS DIV RF 65mVP P 2m S DIV out compensation to detect The input signal for the sec ond stage of drop out detection is pins 8and 35 of IC 351 If drop outs are present in either stage of de...

Страница 57: ...ck the voltage levels on pins 16 and 17 of IC351 Compare these levels to the table in Fig 34 to determine if IC351 or the mechanical control microprocessor IC801 is defective 5 If the signal is presen...

Страница 58: ...Remote control key Each time the STILL button II is pressed the player will switch between the PLAY and STILL modes SLDR REV SCAN Play mode 44 Press and hold down the key With the TRK servo open the p...

Страница 59: ...e SLD to move further outward than the lead out area TILT Servo On Play mode RANDOM PLAY Height Minus TILT Servo OFF Stop mode 14 4 Press and hold down the key Height Plus TILT Servo OFF Stop mode 1 P...

Страница 60: ...sition Slider position is indicated on the TV screen and front panel display TV display information is coded as follows S XXX CD CD active area CDV CDV active area LD LD active area 6 Mechanical Loadi...

Страница 61: ...PSLD 40 4 Without loading a disc into the player place the player into the play mode 5 The DVM should indicate 675 mV DC 50mV If laser power is not within this range adjust VR1 for the proper level C...

Страница 62: ...lens position by placing holder 202440 on lens Caution The laser lens is mounted in the pickup assembly by the focus and tracking coils Extreme caution must be taken when mov ing and handling the las...

Страница 63: ...19 FiLi Filter input for the master PLL 20 PCO 0 1 Z 0 Charge pump output for the master PLL 21 AVss Analog GND 22 CLTV I VCO control voltage input for the master PLL 23 AVDD Analog power supply 5 V 2...

Страница 64: ...0 4 2336 MHz output Changes during variable pitch 58 CI 6M 0 1 o 19 9344 MHz output Changes during variable pitch 59 MD2 1 Digital OUT ON OFF control ON when H and OFF when L 60 DOUT o 1 0 Digital OUT...

Страница 65: ...Synchronized REC control input 35 SYNC OUT 0 Synchronized REC control output 36 POWER ON Power ON OFF H ON L OFF 37 X RESET PD0071 reset 38 X CS M50554 select 39 No connection 40 X SCK 110 Serial data...

Страница 66: ...ignal terminal This terminal is abidirectional data line It transmits the timing for the data transfer after the respective inicrocomputr switches between the output or input mode 19 S11 I Mode Contro...

Страница 67: ...or control 48 V LOAD 49 CCW Loading tilt motor rotation direction control signal output terminal The motor s rotational direction and brake mode are selected by pins 49 and 50 50 CW Pin 49 Countercloc...

Страница 68: ...ive signal output when SLDR in operating at low or mid speeds 20 Capacitor connected pin for setting the slope of the reference triangular wave for the SLDR motor PWM drive during play 21 Resistor con...

Страница 69: ...tput burst signal time axis error output 19 AP31 I Op amp 3invert input 20 AP30 0 Op amp 3invert output 21 AP41 I Op amp 4invert input 22 AP40 0 Op amp 4output for CCD circuit phase compensation 23 SW...

Страница 70: ...z D WorldRadioHistory...

Страница 71: ...o t e C WorldRadioHistory...

Страница 72: ...T LDR300 PSLD 40 1 Printed in USA WorldRadioHistory...

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