VC-M522HM VC-MH722HM VC-MH732HM SERVICE MANUAL SX9R2VC-M522H VIDEO CASSETTE RECORDER VC-M522HM VC-MH722HM VC-MH732HM 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.
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VC-M522HM VC-MH722HM VC-MH732HM 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.
Video recording system: Two rotary heads, helical scan system Video signal: PAL colour and I signals, 625 lines Recording/playing time: 240 min max. with SHARP E-240 tape (PAL SP) 480 min max. with an E-240 tape (LP) Tape width: 12.7mm Tape speed: 23.39 mm/s (PAL SP)
VC-M522HM VC-MH722HM VC-MH732HM 2. DISASSEMBLY AND REASSEMBLY 2-1 DISASSEMBLY OF MAJOR BLOCKS : Remove 4 screws 1. TOP CABINET PWB HOLDER : Remove 2 screws 2 and 7 clips 3. OPERATION (2) : Remove 2 hooks c and 3 hooks d.
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VC-M522HM VC-MH722HM VC-MH732HM 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 2 screws 1 and 1 screw 2 and H/A shield.
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VC-M522HM VC-MH722HM VC-MH732HM 2-3 CARES WHEN REASSEMBLING cassette housing. (Conditions: When mechanism and INSTALLING THE CASSETTE HOUSING PWB have been installed) When the cassette housing is installed on the mechanism, the initial setting is essential condition. 2. Mechanical initial setting...
VC-M522HM VC-MH722HM VC-MH732HM 3. FUNCTION OF MAJOR MECHANICAL PARTS (TOP VIEW) Function Function Full erase head Reverse guide lever ass’y Supply pole base ass’y Casecon drive gear Tension arm ass’y Take-up reel disk Idler wheel ass’y Pinch roller lever ass’y Pinch drive lever ass’y...
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VC-M522HM VC-MH722HM VC-MH732HM FUNCTION OF MAJOR MECHANICAL PARTS (BOTTOM VIEW) Function Function Slow brake Clutch lever Master cam Limiter pulley ass'y Capstan D.D. motor Casecon drive gear Reel belt Shifter...
VC-M522HM VC-MH722HM VC-MH732HM 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.
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VC-M522HM VC-MH722HM VC-MH732HM MAINTENANCE CHECK ITEMS AND EXECUTION TIME Perform the maintenance with the regular intervals as follows so as to maintain the quality of machine. Maintained 500 1000 1500 2000 Possible symptom Remarks Parts hrs. hrs. hrs. hrs. encountered Abnormal rotation or significant vi- Guide roller ass’y...
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VC-M522HM VC-MH722HM VC-MH732HM REMOVING AND INSTALLING THE CASSETTE Notes: 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.
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VC-M522HM VC-MH722HM VC-MH732HM REEL DISK REPLACEMENT AND HEIGHT 4. Assemble the Sup 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.
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VC-M522HM VC-MH722HM VC-MH732HM 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.
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VC-M522HM VC-MH722HM VC-MH732HM Notes: CHECKING AND ADJUSTMENT OF TAKE-UP 1. Hold the torque gauge by hand so that it is not moved. TORQUE IN VIDEO SEARCH REWIND MODE 2. Do not keep the reel disk in lock state. Do not allow long- •...
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VC-M522HM VC-MH722HM VC-MH732HM CHECKING THE VIDEO SEARCH REWIND BACK TENSION • Remove the cassette housing control assembly. • After short-circuiting TP801 provided at the center Tension gauge Pinch roller (facing to the main PWB), plug in the power cord. 8.8 ~ 11.8 N (900 - 1,200gf) •...
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VC-M522HM VC-MH722HM VC-MH732HM 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 ±...
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VC-M522HM VC-MH722HM VC-MH732HM • 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.
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VC-M522HM VC-MH722HM VC-MH732HM REPLACEMENT OF A/C (Audio/Control) HEAD 3. Align the left end of gear of A/C head plate with the punched mark of chassis, tentatively tighten the screws 1. Remove the cassette housing control assembly. 1 and 2 so as to ensure smooth motion of A/C head 2.
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VC-M522HM VC-MH722HM VC-MH732HM A/C HEAD HEIGHT ROUGH ADJUSTMENT HEIGHT ADJUSTMENT OF REVERSE GUIDE • Setting 1. Adjust the height from the mechanism chassis to the Azimuth screw reverse guide lower flange to 13.38 mm, using the reverse guide height adjustment jig, in tape loading state.
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VC-M522HM VC-MH722HM VC-MH732HM Notes: ADJUSTMENT OF TAPE DRIVE TRAIN 1. Previously set the tracking control in the center position, 1. Tape run rough adjustment and adjust the envelop waveform to maximum with X 1 Remove the cassette housing control assembly.
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VC-M522HM VC-MH722HM VC-MH732HM 3 Next, change the alignment tape to VROCPSV(VC- PB CHROMA MH742HM) or VROUBZFS(VC-M332HM) to play- Envelope back. Press the tracking button (+), (–) and change the envelope waveform from max to min and from min to max. At this time adjust the height of supply...
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VC-M522HM VC-MH722HM VC-MH732HM REPLACEMENT OF DRUM D.D. MOTOR 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 Page 5 item 1.
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VC-M522HM VC-MH722HM VC-MH732HM REPLACING THE UPPER AND LOWER DRUM ASSEMBLING OF PHASE MATCHING 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 Page 22 D.D. motor 1.
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VC-M522HM VC-MH722HM VC-MH732HM 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.
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VC-M522HM VC-MH722HM VC-MH732HM 1. Make sure that the loading gear is at the PHASE- INSTALLING THE SHIFTER MATCHING 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.
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VC-M522HM VC-MH722HM VC-MH732HM INSTALLING THE MASTER CAM (AT REAR REPLACEMENT OF LOADING MOTOR • Removal 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.
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VC-M522HM VC-MH722HM VC-MH732HM ASSEMBLY OF CASSETTE HOUSING 1. Drive Gear and R Drive angle ass’y MSPRT0381GEFJ Apply grease Apply grease Apply grease Figure 4-47. 2. Synchro Gear, Drive Gear L and Drive Gear R LANGF9592GEFW Top surface should be free from scratches or soil.
VC-M522HM VC-MH722HM VC-MH732HM 5. ELECTRICAL ADJUSTMENT Notes: • Before the adjustment: Electrical adjustments discussed here are often required after replacement of electronic components and mechani- cal parts such as video heads. Check that the mechanism and all electric components are in good working condition prior to the adjustments, otherwise adjustments can not be completed.
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VC-M522HM VC-MH722HM VC-MH732HM SERVO CIRCUIT ADJUSTMENT ADJUSTMENT OF HEAD SWITCHING POINT CH-1: 1V/div 50µs/div Measuring Dual-trace oscilloscope CH-2: 2V/div 50µs/div CH-2 instrument Colour TV monitor VIDEO OUT Mode Playback Cassette Alignment tape (VROCPSV) 6.5 ± 0.5H (lines) CH-1 V-sync. HEAD Test point Pin(2) of P201 (H.SW.P.) to CH-1,...
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VC-M522HM VC-MH722HM VC-MH732HM ADJUSTMENT OF RF AGC ADJUSTMENT ADJUSTMENT OF PAL SYSTEM FV(False Vertical Sync) OF STILL PICTURE Measuring Colour TV monitor Measuring Colour TV monitor instrument DV voltmeter instrument RF signal at 40CH(by VHF Mode signal generator) Mode Playback still Test point Pin(2)(Sig.) of P1501.
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VC-M522HM VC-MH722HM VC-MH732HM REPLACEMENT OF IC705(E PROM) Servicing precautions When the IC705(E PROM) has been replaced, make the following reprogramming. Depending on models, the IC705(E PROM) has been factory adjusted for it’s memory function. It’s therefor necessary to reprogram the memory function for the model in question.
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VC-M522HM VC-MH722HM VC-MH732HM 2. Memory recording preset level reprogramming. 1. Similarly to the above step 1-1 and 2 the same operate. 2. Using the CHANNEL (+) AND (-) buttons, select the right function numbers continued from recording preset number as has been JP0~JP39, which appear in the fluorescent display tube, referring to the E PROM map.
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VC-M522HM VC-MH722HM VC-MH732HM ROM MAP MODEL MH732HM MH722HM M522HM PAL SP PAL LP NTSC SP NTSC EP JP39 A.DUB JP38 NOT SLOW ATR JP37 S.PIC SERIAL JP36 NTPB JP35 NTSC SKEW JP34 HEAD2 JP33 HEAD1 JP32 HEAD0 JP31 GAMMA JP30...
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VC-M522HM VC-M522HM VC-MH722HM VC-MH722HM VC-MH732HM VC-MH732HM SIGNAL FLOW BLOCK DIAGRAM EE Signal PB Luminance Signal REC Luminance Signal PB Chrominance Signal REC Chrominance Signal...
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VC-M522HM VC-M522HM VC-MH722HM VC-MH722HM VC-MH732HM VC-MH732HM AUDIO BLOCK DIAGRAM (VC-M522HM) EE Signal PB Signal REC Signal...
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VC-M522HM VC-M522HM VC-MH722HM VC-MH722HM VC-MH732HM VC-MH732HM AUDIO BLOCK DIAGRAM (VC-MH722HM/MH732HM) EE Signal PB Signal REC Signal...
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VC-M522HM VC-MH722HM VC-MH732HM POWER CIRCUIT BLOCK DIAGRAM...
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VC-M522HM VC-MH722HM VC-MH732HM SCHEMATIC DIAGRAM NOTES: IMPORTANT SAFETY NOTICE: 1. The unit of resistance "ohm" is omitted (k=1000 BE SURE TO USE GENUINE PARTS FOR SE- ohm, M=1 Meg ohm). CURING THE SAFETY AND RELIABILITY OF 2. All resistors are 1/8 watt, unless otherwise noted.
- OPERATION (2) Unit — (VC-M522HM/MH722HM) DUNTK5736TEVB (VC-M522HM) DUNTK5738TEV3 - OPERATION (2) Unit — (VC-MH732HM) DUNTK5736TEV2 (VC-MH722HM) DUNTK5739TEV2 - F A/V Unit (VC-M522HM) — DUNTK5736TEV3 (VC-MH732HM) DUNTK5739TEV1 - F A/V Unit — Main Unit (VC-MH722HM/MH732HM) TUNER TU1551 VTUATMCB1-101 U Tuner...
VC-M522HM VC-MH722HM VC-MH732HM 12. PACKING OF THE SET TiNS-3584UMZZ (VC-M522HM) QCNW-7870UMZZ TiNS-3563UMZZ (VC-MH722HM) 75ohm Coaxial Cable TiNS-3564UMZZ (VC-MH732HM) Operation Manual Dry batteries SPAKP0051MZZ RRMCG0247AJSA (VC-M522HM/ Foam Bag MH722HM) RRMCG0269AJSB (VC-MH732HM) Infrared Remote Control Unit SPAKX1043UMZZ Buffer Material (Paper) CPAKC4061UMZZ (VC-M522HM)
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VC-M522HM VC-MH722HM VC-MH732HM COPYRIGHT C 1999 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.