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Sec. 2: Deck Mechanism Section and Parts List Section Specifications Standard Maintenance Preparation for Servicing Alignment for Mechanism Exploded views Adjustment Procedures Disassembly/Assembly of Mechanism Parts List Schematic Diagrams Alignment Procedures of Mechanism CBA’ s VIDEO CASSETTE RECORDER 23C-250 23C-250A H7700CVR...
MAIN SECTION VIDEO CASSETTE RECORDER 23C-250 / 23C-250A Sec. 1: Main Section Specifications Preparation for Servicing Adjustment Procedures Schematic Diagrams CBA’ s TABLE OF CONTENTS Specifications..............................1-1-1 Important Safety Precautions..........................1-2-1 Standard Notes for Servicing ..........................1-3-1 Preparation for Servicing ........................... 1-4-1 Cabinet Disassembly Instructions........................
SPECIFICATIONS Description Unit Minimum Nominal Maximum Remark 1. Video 1-1. Video Output (PB) Vp-p FL6A 1-2. Video Output (R/P) Vp-p 1-3. Video S/N Y (R/P) SP Mode, W/O Burst 1-4. Video Color S/N AM (R/P) SP Mode 1-5. Video Color S/N PM (R/P) SP Mode 1-6.
IMPORTANT SAFETY PRECAUTIONS I. Also check areas surrounding repaired locations. Product Safety Notice J. Use care that foreign objects (screws, solder drop- Some electrical and mechanical parts have special lets, etc.) do not remain inside the set. safety-related characteristics which are often not evi- K.
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 their original positions. Chassis or Secondary Conductor Afterwards, do the following tests and confirm the speci- fied values to verify compliance with safety standards.
STANDARD NOTES FOR SERVICING Circuit Board Indications How to Remove / Install Flat Pack-IC a. The output pin of the 3 pin Regulator ICs is indicated 1. Removal as shown. With Hot-Air Flat Pack-IC Desoldering Machine: (1) Prepare the hot-air flat pack-IC desoldering ma- Top View Bottom View chine, then apply hot air to the Flat Pack-IC (about...
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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.
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2. Installation Instructions for Handling Semiconductors (1) Using desoldering braid, remove the solder from the foil of each pin of the flat pack-IC on the CBA so you Electrostatic breakdown of the semiconductors may can install a replacement flat pack-IC more easily. occur due to a potential difference caused by electro- (2) The "...
PREPARATION FOR SERVICING About REC-Safety Switch How to Enter the Service Mode Caution: The REC-Safety Switch is directly mounted on the Main About Optical Sensors CBA. When the Deck Mechanism Assembly is removed Caution: from the Main CBA for servicing, this switch does not work automatically.
CABINET DISASSEMBLY INSTRUCTIONS 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 access to item(s) to be serviced. When reassembling, 3 : Figure Number for reference follow the steps in reverse order.
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[1]Top Case (S-1) (S-1) (L-3) Lift PCB up and over tab [4] Function CBA [8] Main CBA CN505 Fig. 4 (S-1) Spacer (S-3) (S-3) (S-4) Fig. 1 [7]REC Arm [6]Cylinder Assembly Shield (L-2) [5]Deck Assembly [4]Function C.B.A. (L-2) CN501 [2]Front Assembly CN251 (L-1) CN506...
ELECTRICAL ADJUSTMENT INSTRUCTIONS General Note: "CBA" is an abbreviation for "Circuit 1. Head Switching Position Board Assembly". Adjustment Notes: Purpose: To determine the Head Switching point dur- 1. Electrical adjustments are required after replacing ing playback. circuit components and certain mechanical parts. It Symptom of Misadjustment: May cause Head is important to do these adjustments only after all Switching noise or vertical jitter in the picture.
BLOCK DIAGRAMS Servo/System Control Block Diagram TP507 AL+5V IC501 MAIN CBA FUNCTION CBA (SERVO/SYSTEM CONTROL) S-INH RS501 D555 REMOTE KEY-1 CN505 CN651 REMOCON SENSOR SWITCH S-LED KEY-2 KEY SWITCH KEY-2 REC-CTL(+) REC-CTL(-) TP501 FIP501 (DECK ASSEMBLY) F I P AC HEAD ASSEMBLY IC503 (1/3) CN287...
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Video Block Diagram REC-VIDEO SIGNAL PB-VIDEO SIGNAL MODE: SP/REC IC370 (PAL/SECAM DECTECOTR) SECAM CBA TP751 V-OUT MAIN CBA SECAM-CHARA-H Q371 TO CN101 CN751 Q305 CN371 CN370 BUFFER TO SERVO/SYSTEM SECAM-H V-OUT BUFFER SECAM-H CONTROL BLOCK FROM/TO TRICK-H V-IN TRICK-H JACK BLOCK PAL/SECAM Q372 TU-VIDEO...
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Audio Block Diagram PB-AUDIO SIGNAL REC-AUDIO SIGNAL Mode : SP/REC MAIN CBA J981 A-OUT TO CN101 CN751 TU-AUDIO A-OUT JACK BLOCK A-IN TU701 TU-AUDIO 21 IC301 (AUDIO PROCESS) PB-ON LINE MUTE SP/LP-ON (DECK ASSEMBLY) ACE HEAD ASSEMBLY CN287 CN504 A-PB/REC AUDIO 7 A-PB/REC Q402...
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Power Supply Block Diagram NOTE : CAUTION CAUTION ! Fixed voltage (or Auto voltage selectable ) power supply circuit is used in this unit. The voltage for parts in hot circuit is measured using FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, If Main Fuse (F001) is blown, check to see that all components in the power supply REPLACE ONLY WITH THE SAME TYPE T1.6AL/250V FUSE.
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Jack Block Diagram PB-AUDIO SIGNAL REC-AUDIO SIGNAL REC-VIDEO SIGNAL PB-VIDEO SIGNAL JACK CBA IC101 (1/2) INPUT/OUTPUT SELECT JK101 CLAMP CLAMP V-OUT V-IN DRIVE TO CN751 CN101 V-IN CLAMP JK102 TO VIDEO BLOCK V-OUT V-OUT TU-VIDEO V-IN DRIVE CLAMP AL+5V JK102 IC101 (2/2) Q101 TO CN751...
FUNCTION INDICATOR SYMBOL 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 PWR.
SCHEMATIC DIAGRAMS / CBA’S AND TEST POINTS Standard Notes Note: WARNING 1. Do not use the part number shown on these draw- Many electrical and mechanical parts in this chassis ings for ordering. The correct part number is shown have special characteristics. These characteristics in the parts list, and may be slightly different or often pass unnoticed and the protection afforded by amended since these drawings were prepared.
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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. 2. CAUTION: Fixed Voltage (or Auto voltage selectable) power supply circuit is used in this unit. If Main Fuse (F001) is blown, first check to see that all components in the power supply circuit are not defective before you connect the AC plug to the AC power supply.
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Main 1/4 Schematic Diagram 1-8-3 1-8-4 1-8-5 H8624SCM1...
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Main 2/4 Schematic Diagram 1-8-6 1-8-7 1-8-8 H8624SCM2...
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Main 3/4 Schematic Diagram 1-8-9 1-8-10 1-8-11 H8624SCM3...
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Main 4/4 Schematic Diagram H8624SCM4 Function Schematic Diagram H8743SCF 1-8-12 1-8-13 1-8-14...
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Jack Schematic Diagram 1-8-15 1-8-16 H8622SCJ...
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Main CBA Top View CAUTION ! BECAUSE A HOT CHASSIS GROUND IS PRESENT IN THE POWER CAUTION NOTE : Fixed voltage (or Auto voltage selectable ) power supply circuit is used in this unit. SUPPLY CIRCUIT , AN ISOLATION TRANSFORMER MUST BE USED. FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, 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...
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Main CBA Bottom View CAUTION ! BECAUSE A HOT CHASSIS GROUND IS PRESENT IN THE POWER CAUTION NOTE : Fixed voltage (or Auto voltage selectable ) power supply circuit is used in this unit. SUPPLY CIRCUIT , AN ISOLATION TRANSFORMER MUST BE USED. FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, 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...
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Function CBA Top View Function CBA Bottom View BH8700F01031 1-8-25 1-8-26...
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Jack CBA Top View Jack CBA Bottom View BH8700F01021 1-8-27 1-8-28...
WAVEFORMS (TP751 of Main CBA) V-OUT E-E 10usec 50mV x 10 (TP751 of Main CBA) UPPER (TP302 of Main CBA) LOWER V-OUT 0.1V x 10 RF-SW 0.5V x 10 50usec (TP301 of Main CBA) UPPER (TP302 of Main CBA) LOWER C-PB 10mV x 10 RF-SW...
IC PIN FUNCTION IC501 ( SERVO / SYSTEM CONTROL IC ) Signal Active Function Name Level "H" ≥ 4.5V, "L" ≤ 1.0V – – Pins that have * in the Pin No. section on table below are not used. SECAM SECAM Mode at High Signal...
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Signal Active Signal Active Function Function Name Level Name Level Capstan Motor P-ON Power POW- Power Voltage Detection Input C-POW- Control Signal, Signal (FF/REW= Tape End Position "H") END-S Detect Signal Special Automatic OUT TRICK-H Playback="H" in Frequency Control SECAM Mode Signal A-MODE Hi-Fi Tape Video Envelope...
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Signal Active Function Name Level OUT P6 Display Segment – N.U. Not Used – – N.U. Not Used – Notes: Abbreviation for Active Level: PWM ---------------------- Pulse Wide Modulation A/D ------------------------ Analog - Digital Converter 1-11-3 H8743PIN...
LEAD IDENTIFICATIONS BN1L4M-T BN1F4M-T 2SC1815-Y(TPE2) KRA104M BA1F4M-T BD6655FP 2SC1815-GR(TPE2) DTA144ES KTA1266(GR) 2SC3331(T,U) 2SD1246(S,T) KTC3193(Y) 2SC2120-Y(TPE2) KTA1267(Y.GR) KTC3199(Y,GR,BL) KTC3203(Y) 2SA1175(J.H.F) 2SC2785(J.H.F.K) 2SC1815-BL(TPE2) 2SC2058(Q) KRA103M KRC103M DTC124ESA 2SA1015-GR(TPE2) DTA124ESA E C B E C B LA71586M 2SC536NF(NG)-NPA-AT LTV-817(B.C)-F BR24C02F-W QSZAC0RMB046 AT24C02N-10SC M24C02-MN6 LM7158M-TRM LM324D LA7358...
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DECK MECHANISM SECTION VIDEO CASSETTE RECORDER 23C-250 / 23C-250A Sec. 2: Deck Mechanism Section Standard Maintenance Alignment for Mechanism Disassembly/Assembly of Mechanism Alignment Procedures of Mechanism TABLE OF CONTENTS Standard Maintenance............................2-1-1 Service Fixtures and Tools..........................2-2-1 Mechanical Alignment Procedures ........................2-3-1 Disassembly / Assembly Procedures of Deck Mechanism ................
STANDARD MAINTENANCE Service Schedule of Components H: Hours : Check : 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 Tension Lever Sub Assembly AC Head Assembly B573, B574 Reel (S), Reel (T) Capstan Motor Cap Belt...
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Cleaning Cleaning of Audio Control Head Clean the head with a cotton swab. Cleaning of Video Head Procedure Clean the head with a head cleaning stick or chamois cloth. 1. Remove the top cabinet. 2. Dip the cotton swab in 90% isopropyl alcohol and Procedure clean the audio control head.
SERVICE FIXTURE AND TOOLS J-1-1, J-1-2 Ref. No. Name Part No. Adjustment J-1-1 Alignment Tape FL6A Head Adjustment of Audio Control Head J-1-2 Alignment Tape FL6N8 Azimuth and X Value Adjustment of Audio Control (1speed only) Head / Adjustment of Envelope Waveform FL6NS8 (2speed only) Guide Roller Adj.Screwdriver FSJ-0006...
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.
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1. 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 2-3-4, procedure 1-C, step 2.) Equipment required: Dual Trace Oscilloscope VHS Alignment Tape (FL6N8) Guide Roller Adj.
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to apply adequate torque to the shaft of each 1-A. Preliminary/Final Checking and Guide Roller so that the Guide Roller turns prop- Alignment of Tape Path erly. Even when adjusting the height of the Guide Purpose: Roller(s), do not touch these two small screws. To make sure that the tape path is well stabilized.
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6. Press CH DOWN button on the VCR until the CTL 1-D. Azimuth Alignment of Audio/Control/ waveform has shifted from its original position (not Erase Head the position achieved in step 5, but the position of Purpose: CTL waveform in step 4) by approximately To correct the Azimuth alignment so that the Audio/Con- -2msec.
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 1-5-1.) All the following procedures, including those for adjustment and replacement of parts, should be done in Eject mode; see the positions of [48] and [49] in Fig.
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(S-1) (L-1) (S-1) (L-1) (S-2) (S-4) (S-3) (P-1) Fig. DM5 Fig. DM3 Connector Pin D Pin C [53] Pull up Connector Slide [54] Pin A Pin B (L-6) Slot A Slots (S-5) (S-19) Slot A Fig. DM6 First, while pushing the locking tab as shown in the 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-7) (S-9) [13] FFC Cable (S-10) (S-11) [15] ACH Connector [16] 9B (9P) [14] (L-4) ACH Connector AN (9P) (S-6) Belt Fig. DM7 Fig. DM9 (L-2) (S-8) [10] [18] After removing the Screw (S-12), [12] while pressing the Locking Tab (P-3) (L-7) (L-7), remove [17].
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Cap Belt (C-2) (C-3) [20] [24] [26] (P-4) (P-4) [31] Fig. DM11 (S-14) When installing [26], install the spring (P-4) to [31] as shown in the left figure, and then install [26] while Pin on (C-1) pressing the spring (P-4) to bottom the direction of the arrow in of [26]...
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Refer to the Alignment Section, Page 2-4-9. [28] (C-5) (P-5) [38] (S-16) [37] [40] [39] (C-7) [30] [36] [29] (C-6) [32] (C-4) [33] [31] [27] [34] Fig. DM15 [43] [35] Position of Mode Lever when installed (C-10) Pin of [42] Pin of [38] (P-7) [45]...
ALIGNMENT PROCEDURES OF MECHANISM The following procedures describe how to align the Alignment 1 individual gears and levers that make up the tape load- Loading Arm, S and T Assembly ing/unloading mechanism. Since information about the state of the mechanism is provided to the System Con- Install Loading Arm S and T Assembly so that their trol Circuit only through the Mode Switch, it is essential triangle marks point to each other as shown in...
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Alignment 3 Cam Gear (A), Rack Assembly Install the Rack Assembly so that the first tooth on the gear of the Rack Assembly meets the first groove on the Cam Gear (A) as shown in Fig. AL4. Cam Gear (A) Top View Alignment 3 First tooth...
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EXPLODED VIEWS AND PARTS LIST SECTION VIDEO CASSETTE RECORDER 23C-250 / 23C-250A Sec. 3: Exploded views and Parts List Section Exploded views Parts List TABLE OF CONTENTS Exploded Views ..............................3-1-1 Mechanical Parts List............................3-2-1 Electrical Parts List .............................. 3-3-1 Deck Parts List..............................
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Cabinet 2L011 See Electrical Parts List for parts with this mark. 2L011 2L011 Some Ref. Numbers are not in sequence. B529 2B18 2B18 B360 B359 2L011 2L032 2L011 2L032 B361 JACK CBA 2L012 2L021 2L051 2L021 2L061 2L021 2L061 JW751 2L061 2L061 2B22...
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Packing Some Ref. Numbers are not in sequence. Unit 3-1-3 H8740PEX...
! have special characteristics important to safety. Before replacing any of these components, read care- fully the product safety notice in this service manual. Don't degrade the safety of the product through improper servicing. Model: 23C-250 Ref. No. Description Part No. FRONT ASSEMBLY H8743FP...
ELECTRICAL PARTS LIST PRODUCT SAFETY NOTE: Products marked with a Ref. No. Description Part No. ! have special characteristics important to safety. CHIP CERAMIC CAP. B K 0.01µF/50V CHD1JK30B103 Before replacing any of these components, read care- C053 ELECTRIC DOUBLE LAYER CAP. 0.047F/5.5V CA0J473MS014 Z or fully the product safety notice in this service manual.
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Ref. No. Description Part No. Ref. No. Description Part No. C326 CHIP CERAMIC CAP. B K 0.047µF/50V or CHD1JKB0B473 CHIP CERAMIC CAP. F Z 0.1µF/25V CHD1EZ30F104 CHIP CERAMIC CAP. B K 0.047µF/25V or CHD1EKB0B473 C372 CHIP CERAMIC CAP. CH J 680pF/50V or CHD1JJBCH681 CHIP CERAMIC CAP.
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Ref. No. Description Part No. Ref. No. Description Part No. C414 CERAMIC CAP.(AX) B K 820pF/50V or CCA1JKT0B821 CHIP CERAMIC CAP. B K 0.022µF/50V or CHD1JK30B223 CERAMIC CAP.(AX) B J 820pF/50V CCA1JJT0B821 CHIP CERAMIC CAP. B K 0.022µF/25V CHD1EK30B223 C415 ELECTROLYTIC CAP.
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Ref. No. Description Part No. Ref. No. Description Part No. C703 ELECTROLYTIC CAP. 10µF/16V M H7 CE1CMASSL100 ZENER DIODE DZ-8.2BSBT265 NDTB0DZ8R2BS C704 CERAMIC CAP.(AX) F Z 0.1µF/50V CCA1JZTFZ104 D016 RECTIFIER DIODE BA157 or NDQZ000BA157 C705 CERAMIC CAP.(AX) SL J 56pF/50V CCA1JJTSL560 FAST RECOVERY DIODE ERA18-04 QDPZ0ERA1804...
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Ref. No. Description Part No. Ref. No. Description Part No. LINE FILTER 50MH LF-4D-E503 or LLBG00ZKQ009 Q057 TRANSISTOR 2SB892(S) or QQSS002SB892 LINE FILTER 58MH ELF15N902AN or LLBG00ZMS035 TRANSISTOR 2SB892(T) QQST002SB892 LINE FILTER 56MH TLF14CB5630R2 LLBG00ZTU022 Q058 RES. BUILT-IN TRANSISTOR BA1F4M-T or QQSZ00BA1F4M L007 CHOKE COIL 47µH-K...