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No. 5301E VT-FX795A SERVICE MANUAL SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT VIDEO CASSETTE RECORDER March 2003 Digital Media Division, Tokai...
SAFETY PRECAUTION FOR REPAIR 1-1 IMPORTANT SAFETY PRECAUTIONS 1-1-1 Product Safety Notice H. When a power cord has been replaced, check that 5 - 6 kg of force in any direction will not loosen it. Some electrical and mechanical parts have special I.
1-1-3 Safety Check after Servicing Examine the area surrounding the repaired location for damage or deterioration. Observe that screws, parts, Chassis or Secondary Conductor and wires have been returned to their original posi- tions. Afterwards, do the following tests and confirm the specified values to verify compliance with safety Primary Circuit Terminals standards.
1-2 STANDARD NOTES FOR SERVICING 1-2-1 Circuit Board Indications 1-2-3 How to Remove / Install Flat Pack-IC a. The output pin of the 3 pin Regulator ICs is indi- cated as shown. 1. Removal With Hot-Air Flat Pack-IC Desoldering Machine:. Top View Bottom View (1) Prepare the hot-air flat pack-IC desoldering...
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With Soldering Iron: (4) Bottom of the flat pack-IC is fixed with glue to the CBA; when removing entire flat pack-IC, first apply (1) Using desoldering braid, remove the solder from all soldering iron to center of the flat pack-IC and heat pins of the flat pack-IC.
2. Installation 1-2-4 Instructions for Handling Semi-conductors (1) Using desoldering braid, remove the solder from the foil of each pin of the flat pack-IC on the CBA Electrostatic breakdown of the semi-conductors may so you can install a replacement flat pack-IC more occur due to a potential difference caused by electro- easily.
2-2 COMPARISON OF MODELS 2-2-1 Comparison of Features ITEM VT-FX795A VT-FX695A/FX695AC Cabinet Size 360(W) x 92(H) x 216(D) mm 435(W) x 92(H) x 216(D) mm Weight 1.8 kg 2.5 kg Power Consumption 14 W 14 W Video Format Y/C Separation...
2-2-2 Comparison of Main Control ICs ITEM OPERATION VT-FX795A VT-FX695A/FX695AC Video Video Signal Process LA71091M(IC301) LA71091M(IC301) FM Audio Signal Process LA72670M(IC451) LA72655M(IC451) Audio Linear Audio Signal Process Included in IC301 Included in IC301 Main Microcomputer µP MN101D08EFA4(IC501) M37765MAA1N1GP(IC501) VCR-EEP ROM...
2-3 FUNCTION INDICATOR SYMBOLS Note: The following symbols will appear on the indicator panel to indicate the current mode or operation of the VCR. On-screen modes will also be momentarily displayed on the tv screen when you press the operation buttons. Display panel LED MODE INDICATOR ACTIVE...
2-4 OPERATING CONTROLS AND FUNCTIONS Front Panel Remote Control 1. EJECT button 2. NUMBER buttons 3. MENU button POWER EJECT VCR /TV 4. RECORD button POWER CHANNEL REC/IRT STOP/EJECT PLAY F.FWD 5. SPEED button 6. REW button VIDEO IN L-AUDIO IN-R CHANNEL 7.
TROUBLESHOOTING 3-1 TROUBLESHOOTING Video problem 1 (No recording Video) RF INPUT LINE INPUT Check Video signal at pin Check TU701. Check Video signal at pin Check A/V cable. 42 of IC301. 38(or pin40) of IC301. Check signal at pin 89(or pin90) or pin84(or pin83) of IC301. Cleaning Video the Head.
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Audio problem 1 (No recording Normal Audio) RF INPUT LINE INPUT Check SIF signal at pin Check TU701. Check Video signal at pin Check A/V cable. 57 of IC451. 69(or pin71) or pin 7 (or pin9)of IC451. Check Audio signal at pin 6 of IC451. Check IC451.
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Audio problem 3 (No recording Hi-Fi Audio) RF INPUT LINE INPUT Check SIF signal at pin Check TU701. Check Video signal at pin Check A/V cable. 57 of IC451. 69(or pin71) or pin 7 (or pin9) of IC451. Check signal at pin 26 of IC451. Check IC451.
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1] Check for any defective parts while the secondary Power problem rectifying diodes are disconnected. Perform a diode check in both forward and reverse directions through a tester. It is highly recommended that a variable isolation transformer which can monitor current be used. 2] Remove the following components and check for (Alternatively a variable AC source which moni- defects: snubber diode (D051), switching FET (Q001),...
3-2 STANDARD MAINTENANCE 3-2-1 Service Schedule of Components h: Hours : Check I: Change Deck Periodic Service Schedule Ref.No. Part Name 1,000 h 2,000 h 3,000 h 4,000 h Cylinder Assembly Loading Motor Assembly Pulley Assembly B587 Tension Lever Assembly ACE Head Assembly B573,B574 Reel (SP)(D2), Reel (TU)(D2)
3-2-2 Cleaning Cleaning of Audio Control Erase Head Clean the head with a cotton swab. Cleaning of Video Head Procedure Clean the head with a head cleaning stick or chamois 1.Remove the top cabinet. cloth. 2.Dip the cotton swab in 90% Isopropyl alcohol and Procedure clean the audio control erase head.
ADJUSTMENT 4-1 PREPARATION FOR SERVICING 4-1-1 How to Enter the Service Mode About Optical Sensors Caution: An optical sensor system is used for the Tape Start and End Sensors on this equipment. Carefully read and follow the instructions below. Otherwise the unit may operate erratically.
4-2 FIXTURE AND TAPE FOR ADJUSTMENT 1. Alignment Tape 2. Guide Roller Adj. Screwdriver No. 7099046 (MH-1) No. 7099028 3. Flat Screwdriver (Purchase Locally) 4-2-1 How To Use The Fixtures And Tape Item No. Name Part No. Adjustment I Head Switching Point Alignment Tape 7099046 I Tape Interchangeability Alignment...
4-3 ELECTRICAL ADJUSTMENT INSTRUCTIONS General Note: "CBA" is an abbreviation for "Circuit Board Assembly." NOTE: Figure 1 1.Electrical adjustments are required after replacing circuit components and certain mechanical parts. It is important to do these adjustments only after EXT. Syncronize Trigger Point all repairs and replacements have been com- pleted.
4-4 MECHANICAL ALIGNMENT PROCEDURES Explanation of alignment for the tape to correctly run B. Method to place the Cassette Holder in the tape- starts on the next page. Refer to the information below loaded position without a cassette tape on this page if a tape gets stuck, for example, in the 1.
4-4-2 Tape Interchangeability Alignment Note: To do these alignment procedures, make sure that the Tracking Control Circuit is set to the center position every time a tape is loaded or unloaded. (Refer to page 4-7, procedure 1-C, step 2.) Equipment required: Dual Trace Oscilloscope VHS Alignment Tape (MH-1) Guide Roller Adj.
1-A. Preliminary/Final Checking and 3. Check to see that the tape runs without creasing at Alignment of Tape Path Take-up Guide Post [4] or without snaking between Guide Roller [3] and ACE Head. (Fig. M3 and M5) Purpose: 4. If creasing or snaking is apparent, adjust the Tilt To make sure that the tape path is well stabilized.
6. Press CH DOWN button on the unit until the CTL Dropping envelope level at the end of track. waveform has shifted from its original position (not the position achieved in step 5, but the position of CTL waveform in step 4) by approximately -2ms. Make sure that the envelope is simply attenuated (shrinks in height) once CTL waveform passes its original position and is further brought in the minus...
DISASSEMBLY AND REASSEMBLY 5-1 CABINET DISASSEMBLY INSTRUCTIONS 5-1-1. Disassembly Flowchart (1): Identification (location) No. of parts in the figures (2): Name of the part This flowchart indicates the disassembly steps to gain (3): Figure Number for reference access to item(s) to be serviced. When reassembling, (4): Identification of parts to be removed, unhooked, follow the steps in reverse order.
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(S-3) (L-2) (L-2) (S-3) [4]Cylinder Shield Cylinder FE Head Assembly ACE Head Assembly [2] Front Assembly (L-1) [5] Deck Fig. D2 Assembly (S-2) (S-4) (S-2) [6] Main CBA (S-4) (S-4) [3]VCR Chassis Unit From Capstan From From From Motor Cylinder ACE Head FE Head Assembly...
5-2 DISASSEMBLY/ASSEMBLY PROCEDURES OF DECK MECHANISM Before following the procedures described below, be sure to remove the deck assembly from the cabinet. (Refer to CABINET DISASSEMBLY INSTRUCTIONS on page 5-1.) All the following procedures, including those for adjustment and replacement of parts, should be done in Eject mode;...
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REMOVAL INSTALLATION STEP START- REMOVE/*UNHOOK/ /LOC. PART ADJUSTMENT Fig. No. UNLOCK/RELEASE/ CONDITION UNPLUG/DESOLDER Loading Arm (TU) (+)Refer to Alignment [32] [33] DM2,DM14 Assembly Sec.Page 5-12 [34] [2],[25] M Brake (TU) Assembly DM1,DM15 *(P-7), Brake Belt [35] [2],[25] M Brake (SP) Assembly DM1,DM15 *(P-8) [36] [35]...
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(S-1) (S-1) (L-1) (L-3) (L-2) (P-1) Fig. DM5 [46] Fig. DM3 [47] Pin D (L-14) Pin C Pull up Slide Pin A Pin B Slot A (S-2) Slots B Slot A First, while pushing the locking tab as shown at right, slide and pull up the right side on [2] to release Pin A and Pin B from the slots A.
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(S-4) (S-5) [14] (S-6) [16] [15] Desolder from bottom (S-3) Lead with White Stripe Belt View for A Fig. DM7 Fig. DM9 Adj. Screw [11] [18] (L-4) (L-5) (P-3) [17] [13] [19] [12] (P-4) [10] (P-2) (S-7) Pin of [12] Pin of [10] Fig.
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[22] (C-4) (S-8) (C-1) [23] (L-6) [21] (P-5) [20] Cap Belt (P-5) [28] Fig. DM11 When installing [23], install the spring (P-5) to [28] as shown in the left figure, and then install [23] while Pin on pressing the spring (P-5) to bottom the direction of the arrow in of [23]...
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(P-6) [25] [31] Refer to the Alignment (C-3) Section, Page 5-12. (S-9) [29] [33] [30] (L-11) [32] (L-10) (L-8) (C-2) [27] [28] [24] [26] (L-9) Fig. DM14 [36] Position of Mode Lever when installed Break belt Pin of [35] (P-7) Pin of [31] Pin of [34] [34]...
5-3 ALIGNMENT PROCEDURES OF MECHANISM The following procedures describe how to align the Alignment 1 individual gears and levers that make up the tape Loading Arm (SP) and (TU) Assembly loading/unloading mechanism. Since information about the state of the mechanism is provided to the Install Loading Arm (SP) and (TU) Assembly so System Control Circuit only through the Mode Switch, that their triangle marks point to each other as...
6-2 REPLACEMENT PARTS LIST 6-2-1 Mechanical Parts List SYMBOL-NO P-NO DESCRIPTION SYMBOL-NO P-NO DESCRIPTION B483 TJ16909 LOCK LEVER MECHANISM SECTION B487 TJ16911 BAND BRAKE TS18461 FRONT ASSEMBLY B488 TJ16912 MODE LEVER TJ16961 CASE, TOP B491 TJ16913 CAM GEAR TJ16964 JACK BOARD(HIFI) B492 TJ16914 MODE GEAR...
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SYMBOL-NO P-NO DESCRIPTION SYMBOL-NO P-NO DESCRIPTION ACCESSORIES TJ16963 REMOTE CONTROL UNIT TE15081 RF CABLE...
Note: Although some parts in the schematic diagrams have different names from those in 6-2-2 Electrical Parts List the parts list, there is no problem in replacing parts. SYMBOL-NO P-NO DESCRIPTION SYMBOL-NO P-NO DESCRIPTION Q503 TJ15141 PHOTO TRANSISTOR PT204-6B-12 RESISTOR Q504 TJ15141 PHOTO TRANSISTOR PT204-6B-12...
SCHEMATIC, CIRCUIT BOARD AND BLOCK DIAGRAMS 1 SCHEMATIC DIAGRAMS / CBA’S AND TEST POINTS Standard Notes Notes: 1. Do not use the part number shown on these draw- WARNING ings for ordering. The correct part number is shown Many electrical and mechanical parts in this chassis in the parts list, and may be slightly different or have special characteristics.
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LIST OF CAUTION, NOTES, AND SYMBOLS USED IN THE SCHEMATIC DIAGRAMS ON THE FOLLOWING PAGES: 1. CAUTION: FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, REPLACE ONLY WITH THE SAME TYPE FUSE. ATTENTION: POUR UNE PROTECTION CONTINUE LES RISQES D'INCELE N'UTILISER QUE DES FUSIBLE DE MEMO TYPE.
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2 WIRING DIAGRAMS AC CORD FRONT REAR VIDEO AUDIO AUDIO VIDEO AUDIO AUDIO VIDEO AUDIO AUDIO IN (R) IN (L) IN (R) IN (L) OUT (R) OUT (L) ANT-IN ANT-OUT (DECK ASSEMBLY) ACE HEAD ASSEMBLY CL504 AUDIO AE-H ERASE HEAD AE-H/FE-H A-COM AUDIO HEAD...
3-4 Main 4/5 Schematic Diagram CAUTION FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, CAUTION ! REPLACE ONLY WITH THE SAME TYPE FUSE. NOTE : Fixed voltage ( or Auto voltage selectable ) power supply circuit is used in this unit. ATTENTION : POUR UNE PROTECTION CONTINUE LES RISQES The voltage for parts in hot circuit is measured If Main Fuse (F1001) is blown, check to see that all components in the power supply D'INCELE N'UTILISER QUE DES FUSIBLE DE MÊME TYPE.
4 WAVEFORMS (TP301 of Main CBA) UPPER (TP502 of Main CBA) LOWER C-PB 10mV x 10 RF-SW 0.5V x 10 5msec (J23 of Main CBA) UPPER (TP502 of Main CBA) LOWER V-OUT 0.1V x 10 RF-SW 0.5V x 10 50usec (J23 of Main CBA) V-OUT E-E 10usec...
5 CIRCUIT BOARD DIAGRAMS 5-1 Main CBA Top View & Sensor CBA Top View CAUTION CAUTION ! FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, NOTE : Fixed voltage ( or Auto voltage selectable ) power supply circuit is used in this unit. REPLACE ONLY WITH THE SAME TYPE FUSE.
5-2 Main CBA Bottom View CAUTION CAUTION ! FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, NOTE : Fixed voltage ( or Auto voltage selectable ) power supply circuit is used in this unit. REPLACE ONLY WITH THE SAME TYPE FUSE. The voltage for parts in hot circuit is measured If Main Fuse (F1001) is blown, check to see that all components in the power supply ATTENTION : POUR UNE PROTECTION CONTINUE LES RISQES using hot GND as a common terminal.
6-2 Video Block Diagram MAIN CBA TP751 IC501 (OSD) V-OUT Q391 REC VIDEO SIGNAL PB VIDEO SIGNAL MODE: SP/REC CHARACTER BUFFER JK751 V-OUT IC301 TU701 (VIDEO SIGNAL PROCESS/ HEAD AMP) (TUNER UNIT) VIDEO IN Q301 CCD 1H BUFFER DELAY VIDEO OUT CHARA LUMINANCE DOC YNR Y/C COMB...
6-5 Power Supply Block Diagram CAUTION CAUTION ! FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, NOTE : Fixed voltage ( or Auto voltage selectable ) power supply circuit is used in this unit. REPLACE ONLY WITH THE SAME TYPE FUSE. The voltage for parts in hot circuit is measured using If Main Fuse (F001) is blown, check to see that all components in the power supply ATTENTION : POUR UNE PROTECTION CONTINUE LES RISQES hot GND as a common terminal.
7 SYSTEM CONTROL TIMING CHARTS Mode SW : LD-SW LD-SW Position detection A/D Input voltage Limit Symbol (Calculated voltage) 3.76V~4.50V (4.12V) 4.51V~5.00V (5.00V) 0.00V~0.25V (0.00V) 1.06V~1.50V (1.21V) 0.66V~1.05V (0.91V) 1.99V~2.60V (2.17V) 1.51V~1.98V (1.80V) 3.20V~3.75V (3.40V) 0.26V~0.65V (0.44V) 4.51V~5.00V (5.00V) 2.61V~3.19V (2.97V) Note: Note:...
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Still/Slow Control Frame Advance Timing Chart 1) SP Mode 18 RF-SW The first rise of RF-SW after a rise in F-AD signal F-AD (Internal Signal) "H" "H" "Z" C-DRIVE "L" "L" Stop detection (T2) Acceleration Detection (T1) Slow Tracking Value PB CTL Reversal Limit Value 20ms...
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2) LP/SLP Mode 18 RF-SW The first rise of RF-SW after a rise in F-AD signal F-AD (Internal Signal) "H" "H" "Z" C-DRIVE "L" "L" Stop detection (T2) Acceleration Detection (T1) Slow Tracking Value PB CTL Reversal Limit Value 20ms 27 C-F/R 79 H-A-SW 78 ROTA...
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1. EJECT (POWER OFF) -> CASSETTE IN (POWER ON) -> STOP(B) -> STOP(A) -> PLAY -> RS -> FS -> PLAY -> STILL -> PLAY -> STOP(A) PIN NO. LD-SW CL/SS 0.3S 0.3S LM-FWD "M" /REV 0.2S 0.2S 0.2S 0.2S 0.2S "Z"...
8 IC PIN FUNCTION DESCRIPTIONS IC501( SERVO / SYSTEM CONTROL IC ) Signal Active Function Name Level “H” ≥ 4.5V, “L” ≤ 1.0V System Reset Signal Active RESET Signal Function Name Level (Reset=”L”) Power Loading Motor LM-FWD/ Voltage Down 21 OUT FWD/ REV Out- H/Z/L P-DOWN -L...
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Signal Active Signal Active Function Function Name Level Name Level VDD2 VDD2 Video Head Switching Pulse PG-DELAY Low Path Filter Signal Adjusted AFCC Input Signal For Voltage A/D Key Data KEY-2 Low Path Filter Signal 2 44 OUT AFCLPF Output Signal For A/D Key Data KEY-1 Signal 1...