VIDEO CASSETTE RECORDER SERVICE MANUAL SERVICE MANUAL MODELS : EC290W/EC290SW/EC470W/ EC490SW/EC970W/EC990SW CAUTION BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL. EC470W/970W EC290W/290SW/490SW/990SW...
SECTION1 SUMMARY KEY TO ABBREVIATIONS :Alternating Current :Low Pass Filter :Automatic Color Control :Maximum ACSS :Automatic Channel Setting System :Modulator :Adjust MECHA.CTL :Mechanism Control :Audio Erase :Microphone :Automatic Frequency Control :Minimum :Automatic Fine Tuning :Mixer, Mixing :Automatic Gain Control M.M. :Monostable, Multivibrator A.H.SW :Audio Head Switch...
IMPORTANT SAFETY PRECAUTIONS Prior to shipment from the factory, the products are strictly inspected to conform with the recognized product safety and electrical codes of the countries in which they are to be sold. However, in order to maintain such com- pliance, it is equally important to implement the following precautions when a set is being serviced.
SAFETY CHECK AFTER SERVICING Examine the area surrounding the repaired location for damage or deterioration. Observe that screws, parts and wires have been returned to original positions. Afterwards, perform the following tests and confirm the specified values in order to verify compliance with safety standards. •...
PROPOSAL FOR APPLYING SHORT PROTECTION • The Contents of Examination As all the IC that is applied to VCR is controlled by IIC, mutual communication, if Vcc of IC is short or open with detecting ‘Acknowledge’ data of the specific IC according to each power(5V, 5VT) µ-COM gets unable to detect ‘ACK’...
SERVICE NOTICE ON REPLACING EEPROM In case that defective EEPROM of PAL models is replaced, to operate these sets from the initial state MP KEY must be repaired as well before delivering to the customer. If MP KEY isn’t repaired the setting of RF OUT channel or LANGUAGE might be different from that for cus- tormer’s country.
SECTION2 CABINET & MAIN FRAME SERVICE METHOD (1) Disassembly Flow (2) Re-assembly Flow for service like Fig. 2-1 Top Case LED C.B.A Bottom Cover Main C.B.A Front Panel Housing & Deck Assembly Housing & Deck (3) To check and replace Electrical parts Assembly Disassemble the unit according to No.1) Disassembly Flow.
EXPLODED VIEWS 1. Cabinet and Main Frame Section NOTE) Refer to “SECTION 5 REPLACEMENT PARTS LIST” in order to look for the part number of each part. _ OPTIONAL PARTS...
2.Packing Accessory Section NOTE) Refer to “SECTION REPLACEMENT PARTS LIST NOTE) in order to look for the part number of each part. OPTIONAL PARTS CABLE SET ASS'Y (Optional parts) PLUG ASS'Y 1WAY (Optional parts) PLUG ASS'Y 2WAY (Optional parts) INSTRUCTION MANUAL BATTERY PACKING (LF) BAG.
ELECTRICAL ADJUSTMENT PROCEDURES 1. Servo Adjustment 1) PG Adjustment • Test Equipment a) OSCILLOSCOPE b) PAL TEST TAPE (VHS SP) c) JIG REMOCON (AUTO PG SETTING) • Adjustment And Specification MODE MEASUREMENT POINT ADJUSTMENT POINT SPECIFICATION V.Out PLAY 6.5 ± 0.5H H/SW(W714, W715) •...
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ELECTRICAL ADJUSTMENT PROCEDURES • WAVEFORM H/SW 6.5H(416us) Composite VIDEO • Attension and Reference a) The PG checking must do when RF Level is Maximum and SERVO system is Locking (MTR MODE) b) V.H/SW Level is 2Vpp.
ELECTRICAL TROUBLESHOOTING GUIDE 1. Power Circuit(SMPS) (1) No 5.3VA. No 5.3VA. Replace the F101 Is the F101 normal? (Use the same Fuse). Is the BD101 normal? Replace the BD101. Is the R101 normal? Replace the R101. Does the oscillation waveform appear at Is Vcc(about 13~15V) permittable at the the IC101 Pin 7? IC101 Pin 3?
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7. Power Circuit(SMPS) (2) No 12VA.(Capstan) No 12VA. Does 5.3VA work normally? Check whether 5.3VA is out of order. Is the D109 normal? Replace the D109. Check 12VA Line of the Main PCB short. (3) No 12V (Hi-Fi, Buffer) No 12VA. Is Vcc(about 12V) put into the Q152(E)? Replace the Peripheral Circuitry of ZD152.
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7. Power Circuit(SMPS) (4) No 5V No 5V. Is 5.3VA put into the Q155(Q157) collector? Is the Q156 Base “H”? Check the µ-com Control. Is about 4.7V put into the Check the Q156 Q155(Q157) Base? whether it works normally. Check or Replace the Q155(Q157).
2. Servo Circuit Unstable Video in PB Mode. Does the on screen noise level change periodically? Do CTL pulses appear at IC501 pin 97? Does the CFG divide Is the height of the CTL waveform appear at IC501 Head adjusted correctly? pin 87? Do the CTL pulses move Adjust the CTL Head.
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Drum Motor stopped. Does 12V appear at PMC01 PIN8? Does Drum CTL signal appear at PMC01 Check Power. PIN12? Does Drum PWM appear at IC501 Check Connector and Drum Motor Ass’y. Pin 76? Check the Components and foil Pattern Do DPG/FG Pulses appear at PMC01 between IC501 Pin 76 and PMC01 Pin 11? Pin 12 for shorts.
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Capstan Motor Stopped. Does 12VA appear at PMC01 Pin 2? Does 2.8V appear at PMC01 Pin 9? Check Power. Check Connector and Capstan Does PWM wave appear at IC501 Motor Ass’y. Pin 77? Check the Components and foil Patterns Does the CFG signal appear at PMC01 Connected between IC501 Pin 77 and Pin 1? PMC01 Pin 9 for shorts.
3. System & Front Panel Circuit Auto stop. Does SW30 waveform appear at IC501 Pin 18? Do Take-up reel pulses Check the Drum Motor appear at IC501 Pin 80? Signal. Does 5.3V appear at Change IC501. RS501. Replace the Take-Up Reel Photocoupler on Main Check the Power.
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Cassette tape loading is unstable. Is REG 12V applied to PMC01 Pin 8? Is High signal applied to IC501 Pin 58 Check the power. When inserting the CST? Is 5.3V applied to R544? Does Low signal occur form IC501 Pin 60 Check the CST SW and Check the power.
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Non working functon buttons. Is the voltage of IC501 Pin 99, 5V? Does LED CLOCK, LED DOT display change when a function button is Check the power. pressed? Replace the defective Switch. Replace IC501. (Function SW) LED CLOCK, LED DOT doesn’t work. Is 5V applied to IC501 Pins 37 and Check the power circuit.
4. Y/C CIRCUIT (1) No Video in EE Mode, No Video in EE Mode Check the Video Input Does the Video signal Jack. appear at the IC301 Pin 48? (Line In Jack) Is 5V applied to the IC301 Check the 5.2V, 5.4VA Pins 18, 24, 42, 55, 72, 91? Line.
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3. Y/C CIRCUIT (2) When the Y(Luminance) signal doesn’t appear on the screen in PB Mode, Is 5.2VT, 5.4VA applied to the Check the line of the 5.2V IC301 Pins 24, 42, 55, 72, 91? Line. (Power Circuit) Is the I C Bus siganl applied Refer to ‘SYSTEM I C BUS...
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3. Y/C CIRCUIT (3) When the C(Color) signal doesn’t appear on the screen in PB Mode, Is 5.2V/5.3VA applied to the Check the line of the 5.2V/ 5.3VA Line. (Power Circuit) IC301 Pins 24, 42, 55, 72, 91. Is the Color Rotary signal Check the Color Rotary applied to the IC301 Circuit.
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3. Y/C CIRCUIT (4) When the Video signal doesn’t appear on the screen in REC Mode, Is the EE signal normal? Check EE Mode. Is 5.2V/5.3VA applied to the Check the line of the 5.2V/ IC301 Pins 24,42,55,72,91? 5.3VA Line.(Power Circuit) Does PB Mdoe operate Check PB Mode.
5. Tuner/IF circuit (1) No picture on the TV screen No picture on the TV screen Does the Video signal at Is +30V applied to Check 34V line. the TU701 Pin24? TU701 Pin 16? Is +5.2V applied to Check 5.2V line. TU701 Pin 13? Does the Clock signal Check the liC Clock...
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(2) No sound (Mono Model) No sound Check the Vcc of IC301 Pin 18. Check 5.2V power. Check the Tuner Audio signal Chekc the signal flow from TU701 at IC301 Pin 13. Pin21 to IC301 Pin 13. Check the Audio signal at IC301 Pin 11. Replace IC301.
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(3) No sound (Hi-Fi Model) No sound Check the Vcc of IC751 Pins 1, 19, 33. Check 5V power. Check the Tuner SiF signal at IC751 Pin 2. Check the Tuner Audio of TU701 Pin 21. Check the oscillator of IC751 Pins 5, 6. Replace X751.
6. Hi-Fi Circuit (Hi-Fi Model) Hi-Fi Playback. Check the Vcc of No sound IC801.(Pins 34, 40) Check the Hi-Fi Selection Check power. Switch and the Tape quality. Is the RF Envelope at Is the Head switching signal Check IC501 Pin 19. IC801 Pin 44 over 2Vp-p? IC802 Pin 41 O.K? (Audio head switch 25)
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Hi-Fi REC. It is impossible to record and playback Hi-Fi Audio signal. Check Vcc of IC801. (Pins 34,40) Check IC801 Pin 42(Data),Pin 43(CLOCK). Check Power. Do Audio signals appear at IC801 Check ports of µ-COM. Pins 16, 17? Do FM Audio signals appear at IC801 Check Audio input signal of IC801 Pin 36? Pins 2, 3(TU.A.), 6, 7(Scart 1)
CIRCUIT DIAGRAMS 1. Power Circuit Diagram Power is dead. D109, C120 are defective. No power. BD101, R101 are defective. No 12VA and 12V. D102 is defective. No 5.3VA and 5.1V. D106 is defective. Switching dead. IC101 is defective. Power dead. F101 is defective.
3. A/V Circuit Diagram IC301 Pin70 is defective. PB COLOR Signal disappear. D301 or IC301 Pin 80 REC is defective. IC301 Pin 84 is defective. Audio Tracking is failed. IC301 Pin 69, 68 are defective. PB and Recording is failed. (IC301 doesn’t operate.) 8 13 X301 is defective.
4. System Circuit Diagram • Reset is defect. • Set dead. IC504 is defective. 3 4 9 Speaker will not operate. IC201, X201 are defective. Clock setting will not operate. Remote control is Pulse coil not Receive. X501 is defective. OSD will not operate.
DECK MECHANISM DISASSEMBLY 2. Plate Top (Fig. A-2-1) 2) Unhook three Hooks(H3,H4,H5) on bottom side of the Chassis, lift up the Bracket assembly L/M and disassem- 1) Pull the (B) portion of the Plate Top back in direction of ble the Bracket assembly L/D Motor. arrow and separate the right side of it.
DECK MECHANISM DISASSEMBLY Arm Assembly Cleaner (Fig. A-3-1) (S4) Base Assembly A/C Head *(Fig. A-3-3) Head F/E (Fig. A-3-2) Chassis Fig. A-3 9. Arm assembly Cleaner (Fig. A-3-1) 11. Base assembly A/C Head (Fig. A-3-3) 1) Breakaway the (A) portion as Fig. A-3-1 from the 1) Remove the Screw(S4) and lift the Base assembly A/C Embossing of the Chassis, turn the Arm assembly Head up.
DECK MECHANISM DISASSEMBLY Opener Lid (Fig. A-5-2) Assembly Pinch (Fig. A-5-3) Base Assembly P4 Lever T/up (H13) (Fig. A-5-1) (Fig. A-5-4) (H13) Arm T/up (Fig. A-5-5) Chassis Fig. A-5 16. Base assembly P4 (Fig. A-5-1) 19. Lever T/up (Fig. A-5-4)/ 1) Breakaway the (A) portion of the Base assembly P4 from Arm T/up (Fig.
DECK MECHANISM DISASSEMBLY (S7) Base Tension Base Loading (Fig. A-9-2) Arm Assembly Idler Jog (Fig. A-9-1) (Fig. A-9-3) Chassis Fig. A-9 31. Base Loading (Fig. A-9-1) 33. Arm assembly Idler Jog(Fig. A-9-3) 1) Remove the Screw(S7). 1) Make narrower the two parts, (A) and (B), as Fig. A-9-3. 2) Lift the Base Loading up.
DECK MECHANISM ADJUSTMENT • Tools and Fixfures for Service 1. Cassette Torque meter 2. Alignment tape 3. Torque gauge SRK-VHT-303(Not SVC part) Parts No NTSC: DTN-001 600g.Cm ATG Parts No: D00-D006 PAL:DTN-0002 Parts No:D00-D002 4. Torque gauge adaptor 5. Post height adjusting driver 6.
DECK MECHANISM ADJUSTMENT 1.Mechanism Alignment Position Check Purpose:To determine if the Mechanism is in the correct position, when a Tape is ejected. Test Conditions (Mechanism Test Equipment/ Fixture Check Point Condition) • Mechanism and Mode Switch Position • Blank tape •...
DECK MECHANISM ADJUSTMENT 2. Preparation for Adjustment (To set the Cassette without Tape. Cover the Holes of the End Sensors at the both sides of Deck Mechanism to the Loading state the Bracket Side(L) and Bracket Assembly Door to pre- without inserting a Cassette Tape).
DECK MECHANISM ADJUSTMENT 4.Guide Roller Height Adjustment Purpose: To regulate the Height of the Tape so that the Bottom of the Tape runs along the Tape Guide Line on the Lower Drum. 4-1. Preliminary Adjustment Test Equipment/ Fixture Test Conditions (Mechanism Condition) Adjustment Point •...
DECK MECHANISM ADJUSTMENT 5. Audio/Control (A/C) Head Adjustment Purpose: To insure that the Tape passes accurately over the Audio and Control Tracks in exact Alignment in both the Record and Playback Modes. 5-1. Preliminary Adjustment (Height and Tilt Adjustment) Perform the Preliminary Adjustment, when there is no Audio Output Signal with the Alignment Tape. Test Equipment/ Fixture Test Conditions (Mechanism Condition) Adjustment Point...
DECK MECHANISM ADJUSTMENT 5-2. Confirm that the Tape passes smoothly slowly turn the Tilt Adjustment Screw(C) in the Counterclockwise direction. between the Take-up Guide and Pinch Roller(using a Mirror or the naked eye). After completing Step 5-1.(Preliminary Adjustment), NOTE: check that the Tape passes around the Take-up Guide and Pinch Roller without Folding or Curling at the Top or Check the RF Envelope after adjusting the A/C Head, if Bottom.
DECK MECHANISM ADJUSTMENT 7. Adjustment after Replacing Drum Assembly (Video Heads) Purpose: To correct for shift in the Roller Guide and X value after replacing the Drum. Test Conditions Test Equipment/ Fixture Connection Point Adjustment Points (Mechanism Condition) • CH-1: PB RF Envelope •...
MAINTENANCE/INSPECTION PROCEDURE 1 Check before starting repairs The following faults can be remedied by cleaning and oil- ing. Check the needed lubrication and the conditions of cleanliness in the unit. Check with the customer to find out how often the unit is used, and then determine that the unit is ready for inspec- tion and maintenance.
MAINTENANCE/INSPECTION PROCEDURE 4. Supplies Required for Inspection and 2. Required Maintenance Maintence The recording density of a VCR(VCP) is much higher than that of an audio tape recorder. VCR(VCP) components must (1) Grease : Kanto G-311G (Blue) or equivalent be very precise, at tolerances of 1/1000mm, to ensure com- (2) Isopropyl Alcohol or equivalent patiblity with other VCRs.
MAINTENANCE/INSPECTION PROCEDURE (2) Periodic greasing 5-2) Greasing Grease specified locations every 5,000 hours. (1) Greasing guidelines Apply grease, with a cleaning patch. Do not use excess 1) Loading Path Inside & Top side 5) Lever Tension Groove grease. It may come into contact with the tape transport 2) Shaft 6) Clutch Assembly D33 Shaft or drive system.
MECHANISM TROUBLESHOOTING GUIDE 1.Deck Mechanism Auto REW doesn't work. Is the output of END sensor of supply side "H"? “H”: more than 3.5V “L”: less than 0.7V~1V Is the Vcc. voltage of End Check the syscon power. sensor 5V? Replace End sensor. Is the voltage across IR LED Replace LED.
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MECHANISM TROUBLESHOOTING GUIDE AUTO STOP. (PLAY/CUE/REV) Check aligment positions (page 4- 14) Check spring Pinch. In Play/Cue/Rev is the pinch roller in contact with the capstan Is the output of DFG, DPG OK? Replace Drum Motor. shaft. Are there T/up and supply reel Check Servo, Syscon.
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MECHANISM TROUBLESHOOTING GUIDE In PB mode Tape Presence not sensed. Is the Pinch Roller attached Check Alignment positions to the Capstan Motor Shaft? (page 4-14) Does the T/Up Is the Belt ok? Replace the Belt. Reel turn? Check the clutch and the Idler Does the Capstan Motor turn? Assembly.
MECHANISM TROUBLESHOOTING GUIDE 2. Front Loading Mechanism Cassette cannot be inserted. Does the Lever Assembly Is the Lever Assembly Switch Replace or add the Lever Switch work? Spring damaged or omitted? Assembly Switch Spring. Does the CST IN Switch work Replace CST IN Switch.
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MECHANISM TROUBLESHOOTING GUIDE Cassette will not load. Does the CST insert? Does the opener Lid work? Does the Gear Assembly Rack F/L Replace the Opener Lid. work? Replace the Gear Rack F/L. Does the Opener Door work? Does the Arm Assembly F/L work? Is the opener Door assembled correctly? Does the L/D Motor work? Replace the Arm Assembly F/L.
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