1. Manuals
  2. Brands
  3. Sharp Manuals
  4. VCR
  5. VC-A422U
  6. Service manual

Sharp VC-A422U Service Manual

Hide thumbs
Table of Contents

Advertisement

Quick Links

VC-A422U
VC-H822U
1. GENERAL INFORMATION ........................................................................................................... 5
2. DISASSEMBLY AND REASSEMBLY ........................................................................................... 7
3. FUNCTION OF MAJOR MECHANICAL PARTS ......................................................................... 10
5. ELECTRICAL ADJUSTMENT ..................................................................................................... 31
6. MECHANISM OPERATION FLOWCHART AND TROUBLESHOOTING GUIDE ...................... 33
7. TROUBLESHOOTING ................................................................................................................ 39
8. BLOCK DIAGRAM ....................................................................................................................... 50
9. SCHEMATIC DIAGRAM AND PWB FOIL PATTERN ................................................................. 58
10. REPLACEMENT PARTS LIST .................................................................................................... 73
11. EXPLODED VIEW OF MECHANICAL PARTS ........................................................................... 80
12. PACKING OF THE SET .............................................................................................................. 84
SHARP CORPORATION
SERVICE MANUAL
MODELS
In the interests of user-safety (Required by safety regula-
tions in some countries) the set should be restored to its
original condition and only parts identical to those specified
be used.
CONTENTS
VC-A422U/H822U .......... Models for U.S.A. and Canada
This document has been published to be used for
after sales service only.
The contents are subject to change without notice.
1
VIDEO CASSETTE RECORDER
VC-A422U
VC-H822U
VC-A422U
VC-H822U
S41S7VC-A422U
Page

Advertisement

Table of Contents
loading

Related Manuals for Sharp VC-A422U

Summary of Contents for Sharp VC-A422U

  • Page 1: Table Of Contents

    10. REPLACEMENT PARTS LIST ....................73 11. EXPLODED VIEW OF MECHANICAL PARTS ................80 12. PACKING OF THE SET ......................84 VC-A422U/H822U ..Models for U.S.A. and Canada This document has been published to be used for SHARP CORPORATION after sales service only.
  • Page 2 VC-A422U VC-H822U IMPORTANT SERVICE NOTES BEFORE RETURNING THE VIDEO CASSETTE etc.) and measure the AC voltage drop across the RECORDER resistor. Reverse the AC plug on the set and repeat AC voltage measurements for each exposed part. Any reading of 0.45V rms (this corresponds to 0.3mA Before returning the video cassette recorder to the user, perform the following safety checks.
  • Page 3 VC-A422U VC-H822U NOTES DE SERVICE IMPORTANTES AVANT DE RENDRE LE MAGNETOSCOPE pièces métalliques exposées ayant un parcours de retour au châssis (connexions d’antenne, coffret Avant de rendre le magnétoscope à l’utilisateur, effectuer métallique, tétes de vis, boutons et arbres de commande, etc.) et mesurer la chute de tension CA...
  • Page 4 VC-A422U VC-H822U PRECAUTIONS IN PART REPLACEMENT When servicing the unit with power on, be careful to the section marked white all over. This is the primary power circuit which is live. When checking the soldering side in the tape travel mode, make sure first that the tape has been loaded and then turn over the PWB with due care to the primary power circuit.

  • Page 5: General Information

    VC-A422U VC-H822U 1. GENERAL INFORMATION 1-1 FEATURES Only for VC-H822U • 5 sec. Timer Backup • Hi-Fi Stereo Sound • Field-Still/Variable Slow/Frame Advance • Built-in MTS (Multi-channel TV Sound) Decoder • Real-Time Counter (On Screen Display) • Automatic Daylight Saving-Time (D.S.T.) Adjustment Common Features •...
  • Page 6 VC-A422U VC-H822U 1-3 LOCATION OF MAJOR COMPONENTS AND CONTROL...

  • Page 7: Disassembly And Reassembly

    VC-A422U VC-H822U 2. DISASSEMBLY AND REASSEMBLY 2-1 DISASSEMBLY OF MAJOR BLOCKS : Remove 2 screws 1. TOP CABINET : Remove 2 screws 2 and 7 clips 3. FRONT PANEL : Remove 1 screw 4. OPERATION SHIELD ANGLE : Remove 1 screw 5 with shield angle.
  • Page 8 VC-A422U VC-H822U 2-2 DISASSEMBLING THE MECHANISM/MAIN PWB ASSEMBLY 2. Removing the mechanism and cassette housing. 1. When removing the mechanism from the main PWB, Remove 2 screws 4 fixing the cassette housing to the remove the antenna cover 1 screw 1, and remove the mechanism, and remove the cassette housing.
  • Page 9 VC-A422U VC-H822U 2-3 CARES WHEN REASSEMBLING cassette housing. (Conditions: When mechanism and PWB INSTALLING THE CASSETTE HOUSING have been installed) When the cassette housing is installed on the mechanism, the initial setting is essential condition. 2. Mechanical initial setting There are two initial setting methods, namely electrical and Feed the pulley feed gear of loading motor with screw mechanical.

  • Page 10: Function Of Major Mechanical Parts

    VC-A422U VC-H822U 3. FUNCTION OF MAJOR MECHANICAL PARTS (TOP VIEW) Function Function Full erase head Take-up main brake Supply pole base ass’y Pinch drive cam Tension arm A/C head ass’y Idler wheel ass’y Reverse guide lever ass’y Pinch drive lever ass’y...
  • Page 11 VC-A422U VC-H822U FUNCTION OF MAJOR MECHANICAL PARTS (BOTTOM VIEW) Function Function Drum ass’y Reel belt Loading motor Clutch lever Drum drive motor Limiter pulley ass’y Take-up pole base ass’y Shifter Slow brake lever Master cam Capstan D.D. motor...

  • Page 12: Adjustment, Replacement And Assembly Of Mechanical Units

    VC-A422U VC-H822U 4. ADJUSTMENT, REPLACEMENT AND ASSEMBLY OF MECHANICAL UNITS The explanation given below relates to the on-site general service (field service) but it does not relates to the adjustment and replacement which need high-grade equipment, jigs and skill. For example, the drum assembling, replacement and adjustment service must be performed by the person who have finished the technical courses.
  • Page 13 VC-A422U VC-H822U 4-2 MAINTENANCE CHECK ITEMS AND EXECUTION TIME Perform the maintenance with the regular intervals as follows so as to maintain the quality of machine. Maintained 1000 1500 2000 Possible symptom Remarks hrs. hrs. hrs. hrs. encountered Parts Abnormal rotation or significant Guide roller ass’y...
  • Page 14 VC-A422U VC-H822U 4-3 REMOVING AND INSTALLING THE CAS- Notes: SETTE HOUSING 1. When fitting the S/E sensor holder to the cassette controller frame L/R, take care. • Removal 2. Misengagement of teeth of casecon drive gear and drive 1. In the cassette removing mode, remove the cassette.
  • Page 15 VC-A422U VC-H822U 4-5 REEL DISK REPLACEMENT AND HEIGHT 4. Assemble the Supply main brake ass'y. CHECK Notes: • Removal 1. When installing the reel disk, take due care so that the 1. Remove the cassette housing control assembly. tension band ass'y is not deformed and grease does no 2.
  • Page 16 VC-A422U VC-H822U Note: Notes: Whenever replacing the reel disk, perform the height check- 1. Hold the torque gauge by hand so that it is not moved. ing and adjustment. 2. Do not keep the reel disk in lock state. Do not allow long- time measurement.
  • Page 17 VC-A422U VC-H822U Notes: 4-9 CHECKING AND ADJUSTMENT OF TAKE- 1. Hold the torque gauge by hand so that it is not moved. UP TORQUE IN VIDEO SEARCH REWIND 2. Do not keep the reel disk in lock state. Do not allow long- MODE time measurement.
  • Page 18 VC-A422U VC-H822U 4-10 CHECKING THE VIDEO SEARCH REWIND BACK TENSION • Remove the cassette housing control assembly. • After short-circuiting between TP803 and TP802 Tension gauge Pinch roller provided at operation PWB, plug in the power cord. 900 - 1,200gf •...
  • Page 19 VC-A422U VC-H822U 2. Visually check to see if the right edge of the tension pole Tension pole adjuster adjusting range is within the 2.3 ± 0.25 from the right edge of the Sup guide shaft. Tension pole adjuster Sup guide shaft Tension pole 2.3 ±...
  • Page 20 VC-A422U VC-H822U • Adjustment • Checking the brake torque at the take-up side 1. If the indication of torque cassette meter is lower than the setting, shift the tension spring engagement to the part A. Torque gauge 2. If the indication of torque cassette meter is higher than the setting, shift the tension spring engagement to the part B.
  • Page 21 VC-A422U VC-H822U 4-15 REPLACEMENT OF A/C (AUDIO/CONTROL) C head front section) (See the figure below.) 3. Align the left end of gear of A/C head arm with the HEAD punched mark of chassis, tentatively tighten the screws 1. Remove the cassette housing control assembly.
  • Page 22 VC-A422U VC-H822U 4-16 A/C HEAD HEIGHT ROUGH ADJUSTMENT 4-17 HEIGHT ADJUSTMENT OF REVERSE GUIDE • Setting Azimuth screw 1. Adjust the height from the mechanism chassis to the reverse guide lower flange to 13.38 mm, using the reverse guide height adjustment jig, in tape loading state.
  • Page 23 VC-A422U VC-H822U Notes: 4-18 ADJUSTMENT OF TAPE DRIVE TRAIN 1. Previously set the tracking control in the center position, 1. Tape run rough adjustment and adjust the ATR signal to maximum with X value 1 Remove the cassette housing control assembly.
  • Page 24 VC-A422U VC-H822U 3 Next, press the tracking button (+), (–) and change the envelope waveform from max to min and from PB ATR min to max. At this time adjust the height of supply Signal and take-up side guide roller with the adjustment driver (JiGDRiVERH-4) so that the ATR signal changes nearly parallel.
  • Page 25 VC-A422U VC-H822U 4-20 REPLACEMENT OF DRUM D.D. MOTOR 4-19 REPLACEMENT OF THE CAPSTAN D.D. 1. Set the ejection mode. (DIRECT DRIVE) MOTOR 2. Withdraw the main power plug from the socket. • Remove the mechanism from the main PWB (refer to 2- 2 item 1 When removing the mechanism from the main •...
  • Page 26 VC-A422U VC-H822U 4-21 REPLACING THE UPPER AND LOWER 4-22 ASSEMBLING OF PHASE MATCHING DRUM ASSEMBLY MECHANISM COMPONENTS • Assemble the phase matching mechanism compo- • Replacement (Perform in the numerical order) nents in the following order. 1 Remove the motor as stated in 4-20 D.D. motor replace- 1.
  • Page 27 VC-A422U VC-H822U 1Insert Reverse Guide Lever Ass’y Insert reverse guide lever ass'y 2 Insert pinch drive cam Align here. Turn the reverse guide lever assembly counterclockwise Fit the pinch drive cam so that the notch of pinch to the stopper.
  • Page 28 VC-A422U VC-H822U 1. Make sure that the loading gear is at the Phase-Match- 4-23 INSTALLING THE SHIFTER ing point 1 as shown below. 2. Install, paying attention to insert point 5 and release point 3. Drum 3. For the phase matching at the insert point 1, see the Capstan Phase-Matching point 2 as shown below.
  • Page 29 VC-A422U VC-H822U 4-24 INSTALLING THE MASTER CAM (AT 4-25 REPLACEMENT OF LOADING MOTOR • Removal REAR SIDE OF MECHANISM CHASSIS) 1. Make sure beforehand that the shifter is at the point as shown below. 2. Place the master cam in the position as shown below.
  • Page 30 VC-A422U VC-H822U 4-26 ASSEMBLY OF CASSETTE HOUSING 1. Drive Gear and R Drive angle ass’y MSPRT0381AJFJ Apply grease Apply grease Apply grease Figure 4-47. 2. Synchro Gear, Drive Gear L and Drive Gear R LANGF9592AJFW Top surface should be free from scratches or soil.

  • Page 31: Electrical Adjustment

    VC-A422U VC-H822U 5. ELECTRICAL ADJUSTMENT Notes: • Before the adjustment: Electrical adjustments discussed here are often required after replacement of electronic components and mechanical parts such as video heads. Check that the mechanism and all electric components are in good working condition prior to the adjustments,otherwise adjustments cannot be completed.
  • Page 32 VC-A422U VC-H822U SERVO CIRCUIT ADJUSTMENT 5-2 ADJUSTMENT OF FV (False Vertical Sync) OF STILL PICTURE 5-1 ADJUSTMENT OF HEAD SWITCHING Measuring Color TV monitor POINT instrument Measuring Dual-trace oscilloscope Mode Playback still instrument Cassette Self-recorded tape (SP mode) Mode Playback...
  • Page 33 VC-A422U VC-H822U...
  • Page 34 VC-A422U VC-H822U...
  • Page 35 VC-A422U VC-H822U...
  • Page 36 VC-A422U VC-H822U...
  • Page 37 VC-A422U VC-H822U...
  • Page 38 VC-A422U VC-H822U...
  • Page 39 VC-A422U VC-H822U...
  • Page 40 VC-A422U VC-H822U...
  • Page 41 VC-A422U VC-H822U...
  • Page 42 VC-A422U VC-H822U...
  • Page 43 VC-A422U VC-H822U...
  • Page 44 VC-A422U VC-H822U...
  • Page 45 VC-A422U VC-H822U...
  • Page 46 VC-A422U VC-H822U...
  • Page 47 VC-A422U VC-H822U...
  • Page 48 VC-A422U VC-H822U...
  • Page 49 VC-A422U VC-H822U...

  • Page 50: Block Diagram

    VC-A422U VC-A422U VC-H822U VC-H822U 8. BLOCK DIAGRAM SYSTEM SERVO BLOCK DIAGRAM USMODEL̲SYSBLO.eps 50~51...
  • Page 51 VC-A422U VC-A422U VC-H822U VC-H822U SIGNAL FLOW BLOCK DIAGRAM(VC-A422U) 52~53...
  • Page 52 VC-A422U VC-A422U VC-H822U VC-H822U SIGNAL FLOW BLOCK DIAGRAM(VC-H822U) 54~55...
  • Page 53 VC-A422U VC-H822U POWER CIRCUIT BLOCK DIAGRAM...
  • Page 54 VC-A422U VC-H822U SCHEMATIC DIAGRAM • The indicated voltages in the following diagram IMPORTANT SAFETY NOTICE: are measured with an SSVM, upon receiving color bars (400 Hz sound signal) in either the PARTS MARKED WITH " å " ( ) ARE...

  • Page 55: Schematic Diagram And Pwb Foil Pattern

    VC-A422U VC-A422U VC-H822U VC-H822U 9. SCHEMATIC DIAGRAM AND PWB FOIL PATTERN MAIN CIRCUIT(1) J202 G0006AJ(H822U/UC) F0065AJ(A422U/UC) BLN-0090GE * VOLTAGE MEASUREMENT MODE PB ..Parentheses ( REC ..Without Parentheses 58~59...
  • Page 56 VC-A422U VC-A422U VC-H822U VC-H822U MAIN CIRCUIT(2) 2PD601AR 2PB709AR J201 L0006AJZZ(H822U/UC) H0011AJZZ(A422U/UC) 2PD601AR 2PD601AR * VOLTAGE MEASUREMENT MODE PB ..Parentheses ( REC ..Without Parentheses 60~61...
  • Page 57 VC-A422U VC-A422U VC-H822U VC-H822U MAIN CIRCUIT(3) (H822U) (A422U) (ML) 2PB709AR * VOLTAGE MEASUREMENT MODE PB ..Parentheses ( REC ..Without Parentheses 62~63...
  • Page 58 VC-A422U VC-A422U VC-H822U VC-H822U MAIN CIRCUIT(4) 2PD601AR 2PD601AR 2PD601AR * VOLTAGE MEASUREMENT MODE PB ..Parentheses ( REC ..Without Parentheses 64~65...
  • Page 59 VC-A422U VC-A422U VC-H822U VC-H822U LCD CIRCUIT U0085GE * VOLTAGE MEASUREMENT MODE PB ..Parentheses ( REC ..Without Parentheses 66~67...
  • Page 60 VC-A422U VC-H822U OPERATION CIRCUIT * VOLTAGE MEASUREMENT MODE PB ..Parentheses ( REC ..Without Parentheses...
  • Page 61 VC-A422U VC-H822U PWB FOIL PATTERN OPERATION PWB LCD PWB...
  • Page 62 VC-A422U VC-A422U VC-H822U VC-H822U MAIN PWB 70~71...
  • Page 63 VC-A422U VC-H822U - M E M O -...

  • Page 64: Replacement Parts List

    Pour que votre commande soit rapidement et correctement remplie, 3. PART NO. 4. DESCRIPTION veuillez fournir les renseignements suivants. in USA : Contact your nearest SHARP Parts Distributor to order. 1. NUMERO DU MODELE 2. NO. DE REF For location of SHARP Parts Distributor, Please Call Toll-free;...
  • Page 65 VCKYCY1HF103Z V 0.01 50V Ceramic å L901 RCiLF0312GEZZ J Coil(VC-H822U/UC) C307 VCKYCY1HF103Z V 0.01 50V Ceramic å L901 RCiLF0005AJZZ V Coil(VC-A422U/UC) C308 VCKYCY1HB562K V 5600p 50V Ceramic å L923 RCiLP0147GEZZ J Coil, 10µH C309 VCKYCY1HB562K V 5600p 50V Ceramic å L924 RCiLP0147GEZZ J Coil, 10µH...
  • Page 66 VC-A422U VC-H822U Ref. No. Part No. Description Code Ref. No. Part No. Description Code C501 VCEA9M0JW107M V 100 6.3V Electrolytic C678 VCKYCY1HF103Z V 0.01 50V Ceramic C502 VCKYCY1CF104Z V 0.1 16V Ceramic (VC-H822U/UC) C503 VCKYCY1HB472K V 4700p 50V Ceramic C679 VCKYCY1CF224Z V 0.22...
  • Page 67 VC-A422U VC-H822U Ref. No. Part No. Description Code Ref. No. Part No. Description Code å C932 R619 VRS-CY1JF470J V 47 1/16W Metal Oxide VCEA9M1HW104M V 0.1 50V Electrolytic å C933 R620 VRS-CY1JF153J V 15k 1/16W Metal Oxide VCEA9M1HW104M V 0.1...
  • Page 68 VC-A422U VC-H822U Ref. No. Part No. Description Code Ref. No. Part No. Description Code å R917 R721 VRS-CY1JF223J V 22k 1/16W Metal Oxide VRD-RA2BE562J V 5.6k 1/8W Carbon å R927 R722 VRS-CY1JF473J V 47k 1/16W Metal Oxide VRD-RA2BE102J V 1k 1/8W Carbon å...
  • Page 69 VC-A422U VC-H822U Ref. No. Part No. Description Code Ref. No. Part No. Description Code R886 VRD-RA2BE472J V 4.7k 1/8W Carbon MLEVP0301AJZZ V Reverse Guide Lever Ass’y AL MLEVP0275AJZZ V Reverse Guide Drive Lever AD SWITCHES MLEVP0292AJZZ V Slow Brake Lever...
  • Page 70 PSPAP0009AJZZ V Reverse Guide Adjusting CPNLC2907TEV1 V Front Panel Ass'y (VC-A422U/UC) LX-WZ1041GE00 J CW 2.6-6-0.5 CAM 500-1 ————— V Front Panel(VC-A422U/UC) — XBPSD30P06000 V Drum Base Mounting (Not Replacement Item) Screw(SW 3P+6S) 500-1 ————— V Front Panel(VC-H822U/UC) — LX-WZ1098GE00 J CW 2.6-4.7-0.5 RED...

  • Page 71: Exploded View Of Mechanical Parts

    VC-A422U VC-H822U 11. EXPLODED VIEW OF MECHANICAL PARTS Ref. No. Part No. Description Code Ref. No. Part No. Description Code MECHANISM CHASSIS PARTS 202-1 202-2 35-1 35-2...
  • Page 72 VC-A422U VC-H822U CASSETTE HOUSING CONTROL PARTS Ref. No. Part No. Description Code Ref. No. Part No. Description Code...
  • Page 73 VC-A422U VC-H822U CABINET PARTS Ref. No. Part No. Description Code Ref. No. Part No. Description Code VC-H822U VC-A422U VC-H822U VC-A422U...
  • Page 74 VC-A422U VC-H822U Ref. No. Part No. Description Code FRONT PANEL PARTS(VC-A422U/H822U) Ref. No. Part No. Description Code 500-4 500-1 500-6 500-2 500-7 500-8 500-3 500-5 PRECAUTION ON FRONT PANEL SET-UP Cassette cover Front panel Cassette housing Cassette cover open lever...

  • Page 75: Packing Of The Set

    VC-A422U VC-H822U Ref. No. Part No. Description Code Ref. No. Part No. Description Code 12. PACKING OF THE SET Setting position of the Knobs RF conv. CH. preset at "3" channel Accessories TiNS-3944AJZZ Instruction Book (VC-A422U/H822U) TiNS-3970AJZZ Instruction Book (VC-H822UC)
  • Page 76 VC-A422U VC-H822U - M E M O -...
  • Page 77 Part No. Description Code © COPYRIGHT 2001 BY SHARP CORPORATION ALL RIGHTS RESERVED. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of the publisher.

This manual is also suitable for:

Vc-h822u

Table of Contents