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FILE NO. 120-200222 SERVICE MANUAL VIDEO CASSETTE RECORDER V-852EW FEB, 2002...
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TOTAL CONTENTS 1. Precautions 2. Reference Information 3. Product Specifications 4. Disassembly and Reassembly 5. Alignment and Adjustment 6. Exploded View 7. Replacement Parts List 8. Block Diagram 9. PCB Diagrams 10. Schematic Diagrams...
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Alternatively, wear a discharging Wrist-strap device. (Be sure to remove it prior to applying power--this is an electric shock precaution.) Toshiba...
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Always inspect for pinched, out- of-place, or frayed wiring. Do not change the spacing between components and the printed circuit board. Check the AC power cord for damage. Make sure that leads and components do not touch thermally hot parts. Toshiba...
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2. Reference Information 2-1 Operation of Controls Toshiba...
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Reference Information 2-2 IC Blocks 2-2-1 IC301 (LA71750M) Toshiba 2-25...
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Reference Information 2-2-2 IC501 (LA72646M) 2-26 Toshiba...
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Reference Information 2-2-3 IC601 (uPD784927GF) Toshiba 2-27...
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Reference Information MEMO 2-28 Toshiba...
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68 dB min (IHF A filter) Frequency response 20Hz - 20kHz Power requirement 220-240V (AC 50Hz) Power consumption Approx. 17 watts Operation temperature 41°F-104°F (5°C-40°C) Operation humidity 10%-75% Weight 3,5 Kg (net) Dimensions (WxHxD) 430 x 94 x 409 mm Toshiba...
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4-1-3 Ass’y Front A/V PCB Removal Disconnect the CN708/CN710 from the Ass'y PCB-Main and then lift the Ass'y Function PCB up. ´ RELEASE 3 HOOKS (Bottom View) Fig. 4-2 Ass’y Front Panel Removal CN708 CN701 Fig. 4-3 Ass’y Front A/V PCB Removal Toshiba...
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4-2-1 Top View Œ ´ ˇ ¨ ˆ Ø Fig. 4-5 Top parts Location-1 Œ GEAR FL CAM ´ MOTOR LOADING ASS’Y ˇ LEVER FL ARM ASS’Y ¨ HOLDER FL CASSETTE ASS’Y ˆ LEVER FL DOOR Ø SLIDER FL DRIVE Toshiba...
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´ CYLINDER ASS’Y ˝ GEAR IDLE ˇ ACE HEAD ASS’Y Ô LEVER IDLE ¨ LEVER UNIT PINCH ASS’Y LEVER T BRAKE ASS’Y ˆ LEVER #9 GUIDE ASS’Y Ò DISK T REEL Ø LEVER TENSION ASS’Y ∏ BAND BRAKE ASS’Y Toshiba...
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Œ GEAR JOINT 1 ´ GEAR JOINT 2 ˇ BRACKET GEAR ¨ MOTOR CAPSTAN ASS’Y ˆ LEVER T LOAD ASS’Y Ø GEAR LOADING DRIVE ∏ LEVER S LOAD ASS’Y ” HOLDER CLUTCH ASS’Y ’ BELT PULLEY ˝ SLIDER CAM Toshiba...
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"A" of the Lever FL Cassette-R ´ at disassembling and reassembling. Fig. 4-9 Lever FL Door Removal RAIL [B] Œ HOLDER FL ´ LEVER FL CASSETTEE -R CASSETTEE ASS`Y "A" BOSS [A] Fig. 4-8 Holder FL Cassette Ass’y Removal Toshiba...
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Œ LEVER FL ARM ASS`Y Fig. 4-12 Lever FL Arm Ass’y Removal ´ GEAR FL CAM Œ SLIDER FL DRIVE Fig. 4-10 Slider FL Drive Removal Œ GEAR FL CAM GEAR WORM WHEEL POST TIMING POINT Fig. 4-11 Gear FL Cam, Gear Worm Toshiba...
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Œ CABLE FLAT LOADING MOTOR CYLINDER CONNECTING PART CONNECTING PART "B" ¨ DAMPER ´ CONNECTOR WAFER CAPSTAN Œ GEAR WORM WHEEL "A" "C" Fig. 4-13 Gear Worm Wheel Removal ˇ CONNECTOR WAFER Fig. 4-14 Cable Flat Removal Toshiba...
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TIMING POINT 3 Fig. 4-18 Gear Loading Drive, Slider Cam, Lever T, S Load Ass’y Removal PIN A PIN C PIN D PIN B ˇ SLIDER CAM Fig. 4-19 Gear Loading Drive, Slider Cam, Lever Load S, T Ass’y Assembly Toshiba 4-10...
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Main Base to the Mark[B]. ˇ BAND BRAKE ASS`Y ´ LEVER TENTION ASS`Y Œ SPRING TENTION LEVER Fig. 4-20 Lever Pinch Drive, STOPPER "A" Lever Tension Drive Removal MARK[B] Fig. 4-21 Lever Tension Ass’y, Band Brake Ass’y Removal 4-11 Toshiba...
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´ GEAR IDLE "B" ´ GEAR IDLE HOOK "C" HOOK(A) ˇ SPRING BRAKE Œ LEVER S BRAKE ASS`Y HOOK(C) HOOK(B) ´ LEVER T BRAKE ASS`Y Fig. 4-23 Gear Idle Ass’y Removal Fig. 4-22 Lever Brake S, T Ass’y Removal Toshiba 4-12...
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Center Ass'y as shown in detail B. ´ DISK T REEL Œ WASHER SLIT ´ HOLDER CLUTCH ASS`Y Fig. 4-24 Disk S, T Reel Removal DETAIL A <BAD> SPRING <GOOD> DETAIL B SPRING <BAD> <GOOD> Fig. 4-25 Holder Clutch Ass’y Removal 4-13 Toshiba...
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´ GEAR CENTER ASS`Y Fig. 4-28 Guide Cassette Door Removal Fig. 4-26 Lever Up Down Ass’y Removal GEAR CENTER ASS'Y GUIDE LEVER UP DOWN ASS'Y RING GEAR POST HOOK MAIN BASE Fig. 4-27 Lever Up Down Ass’y Removal Toshiba 4-14...
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Œ LEVER UNIT PINCH ASS`Y Œ SPRING #9 GUIDE ´ LEVER #9 GUIDE ASS`Y "B" ´ PLATE JOINT ˇ SPRING PINCH DRIVE Fig. 4-30 Lever #9 Guide Ass’y Removal Fig. 4-29 Lever Unit Pinch Ass’y, Plate Joint, Spring Pinch Drive Removal 4-15 Toshiba...
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Ass’y ´. 2) Lift the FE Head ´. 2) Remove the screw Œ. 3) Lift the ACE Head Ass’y ´. Œ FE HEAD Œ SCREW ´ HEAD ACE ASS`Y Fig. 4-31 FE Head Removal Fig. 4-32 ACE Head Removal Toshiba 4-16...
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2) When reinstalling, Don't push down too much on Screw Driver. Œ 3 SCREWS Fig. 4-33 Slider S, T Ass’y Removal ´ PLATE GROUND DECK ˇ CYLINDER ASS'Y Fig. 4-34 Plate Ground Deck, Cylinder Ass’y Removal 4-17 Toshiba...
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Main Base. After reinstalling, adjusting the tape transport system again. ´ 3 SCREWS Fig. 4-35 Belt Pulley Removal Œ DAMPER CAPSTAN ˇ MOTOR CAPSTAN ASS'Y Fig. 4-36 Damper Capstan,Motor Capstan Ass’y Removal Toshiba 4-18...
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3) Rotate Gear Worm Œ clockwise using screw driver Œ HOOK again up to the state of eject mode and then pick out the tape.(Refer to Fig.4-39) SLEEVE-HEAD CLEANER FRAME Fig. 4-38 Post #8 Guide Ass’y Removal Fig. 4-40 4-19 Toshiba...
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∆ ∆ CAPSTAN MOTOR PULLEY BELT PULLEY ∆ HOLDER CLUTCH ASS’Y GEAR CENTER ASS’Y GEAR IDLE (2Point) LOADING MOTOR BAND BRAKE ASS’Y BRAKE T ASS’Y ∆ : Cleaning O : Check and replacement in necessary : Add Oil Toshiba 4-20...
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X-Point (Tracking Center) Adjustment TV VOL I.SELECT ENTER F.ADV INDEX COUNT/TR CLR/RST MENU / TIMER TXT/TV NVRAM Option Setting PLAY SLOW PAUSE/STILL CURSOR STOP SP/LP AUDIO DISPLAY TV/VIDEO Head Switching Adjustment A.DUB SAT.MONI. SAT.CONT. PROG. EJECT PICTURE VT-852EW Fig. 5-1 Toshiba...
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Alignment and Adjustment 5-1-2 SW713 location for adjustment mode setting SW701 SW703 SW713 PRESS Fig. 5-2 Main PCB (Top View) Toshiba...
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Fig. 5-3 Location of Tape Transport Adjustment PINCH ROLLER FE HEAD CYLINDER ASS'Y GUIDE ROLLER "S" GUIDE ROLLER "T" POST TENSION #8 GUIDE POST #9 GUIDE POST #3 GUIDE POST MAIN BASE ACE HEAD CAPSTAN SHAFT Fig. 5-4 Tape Travel Diagram Toshiba...
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Test point : TP601 (Control Pulse) TP602 (H’D S/W -Trigger) TP301 (Envelope) TP302 (Audio output) TP303 (Video output) Test tape : ST-N1 BLANK TAPE : T-160 AUDIO OUTPUT ENVELOPE HEAD SWITCHING Fig. 5-5 Location of Test point (Main PCB-Top View) Toshiba...
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4) Connect the CH-1 probe to TP303 (Envelope) the CH-2 probe to TP601 (H’D switching pulse) and then trigger to CH-1. 5) Insert the (-) driver into the X-Point adjustment hole and adjust it so that envelope waveform is maximum. 6) Turn the Power off. Toshiba...
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) driver to obtain a flat video RF envelope as shown in Fig. 5-11. IDEAL ENVELOPE S HEIGHT TOO HIGH S HEIGHT TOO LOW T HEIGHT TOO HIGH T HEIGHT TOO LOW GUIDE ROLLER S GUIDE ROLLER T Fig. 5-11 Guide Roller S, T Height Adjustment Toshiba...
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3) Brake is operated by slider cam at FF/REW mode. 4) Transportation of accurate driving force is done by gears. (Gear Center Ass’y) Note : If the spec. does not meet the followings speci- fications, replace the holder clutch ass’y and then recheck. Toshiba...