Sharp VC-H800X User manual

1
VC-H800X
VIDEO CASSETTE RECORDER
SERVICEMANUAL
CONTENTS
Page
1. SPECIFICATIONS................................................................................................................. 3
2. DISASSEMBLY AND REASSEMBLY ................................................................................... 4
3. FUNCTION OF MAJOR MECHANICAL PARTS................................................................... 7
4. ADJUSTMENT, REPLACEMENT AND ASSEMBLY OF MECHANICAL UNITS.................. 9
5. ELECTRICAL ADJUSTMENT ............................................................................................. 28
6. MECHANISM OPERATION FLOWCHART AND TROUBLESHOOTING GUIDE .............. 32
7. TROUBLESHOOTING ........................................................................................................ 38
8. BLOCK DIAGRAM............................................................................................................... 53
9. SCHEMATIC DIAGRAM AND PWB FOIL PATTERN......................................................... 62
10. REPLACEMENT PARTS LIST............................................................................................ 82
11. EXPLODED VIEW............................................................................................................... 92
12. PACKING OF THE SET ...................................................................................................... 96
SHARP CORPORATION
In the interests of user-safety (Required by safety regula-
tions in some countries) the set should be restored to its
originalcondition andonly partsidentical tothosespecified
be used.
MODEL VC-H800X
SY9S8VC-H800X

2
VC-H800X
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.
Make readjustment, if needed after replacement of part, with the mechanism and its PWB in position in the main frame.
(1) Start and end sensors: Q701 and Q702
Insert the sensor’s projection deep into the upper hole of the holder. Referring to the PWB, fix the sensors tight
enough.
(2) Photocoupler: IC902
Refer to the symbol on the PWB and the anode marking of the part.
(3) Cam switches A and B: D708 and D709.
Adjust the notch of the part to the white marker of the symbol on the PWB. Do not allow any looseness.
(4) Take-up and supply sensors: D707 and D706.
Be careful not to confuse the setting direction of the parts in reference to the symbols on the PWB. Do not allow any
looseness.

3
VC-H800X
1. SPECIFICATIONS
Format: VHS PAL/NTSC standard
Video recording system: Rotary, slant azimuth two heads helical scan system
Video signal: PAL Colour or monochrome (CCiR system B/G ) signals
Recording/playing time: 240 min max. with SHARP E-240 tape (PAL: SP mode)
480 min max. with SHARP E-240 tape (PAL: LP mode)
160 min max. with SHARP T-160 tape (NTSC: SP mode)
480 min max. with SHARP T-160 tape (NTSC: EP mode)
Tape width: 12.7mm
Tape speed: 23.39 mm/s (PAL: SP mode)
11.70 mm/s (PAL: LP mode)
33.35 mm/s (NTSC: SP mode)
16.67 mm/s (NTSC: LP mode) (Playback only)
11.12 mm/s (NTSC: EP mode)
Antenna: 75 ohm unbalanced
Receiving channel: VHF Channel AU0 - AU12, UHF Channel AU28 - AU69
RF converter output signal: UHF Channel AU28 - AU69 Adjustable preset to AU37
Power requirement: 240V/50Hz
Power consumption: Approx. 19W (Approx 1W Max at low power mode)
Operating temperature: 5°C to 40°C
Storage temperature: –20°C to 55°C
Weight: Approx. 3.9 kg
Dimensions: 430 mm (W) x 281 mm (D) x 92 mm (H)
VIDEO
Input: 1.0 Vp-p, 75 ohm
Output: 1.0 Vp-p, 75 ohm
S/N ratio: 45 dB (PAL-SP)
Horizontal resolution: 250 lines (PAL-SP)
AUDIO 0 dBs = 0.775 Vrms
Input: Line 1: -8 dBs/47k ohm
Line 2: -8 dBs/47k ohm
Output: Line -8 dBs/1k ohm
S/N ratio: 43 dB (SP mode)
Frequency responce: 80 Hz ~ 10 kHz (SP mode)
80Hz ~ 5 kHz (LP/EP mode)
Hi-Fi dynamic range: 85dB min.
Hi-Fi Wow and flutter 0.005% max.
Hi-Fi Frequency responce: 20 Hz ~ 20 kHz (SP mode)
Hi-Fi distortion: 0.5% max.
Hi-Fi Crosstalk: 55dB min.
Accessories included: 75 ohm coaxial cable
Operation manual
Infrared remote control
Battery
Note: The antenna must correspond to the new standard DIN 45325
(IEC 169 - 2) for combined UHF/VHF antenna with 75 ohm connector.
Aspartofourpolicyofcontinuousimprovement,wereservethe
right to alter design and specifications without notice.

4
VC-H800X
cb
b
a
A
B
D
D
D1
D1
A
B
C
15
11
11 11
567
8
8
c
9
10
16
15
13
14
1
1
14
12
C1
3
3
4
C
10
C1
2
SHARP
17
2. DISASSEMBLY AND REASSEMBLY
2-1 DISASSEMBLY OF MAJOR BLOCKS
TOP CABINET
SHIELD
ANGLE
ANTENNA
TERMINAL
COVER
MECHANISM/
MAIN PWB
ASSEMBLY
MAIN FRAME
FRONT PANEL
JACK PWB
FRONT A/V
PWB
PWB HOLDER
BOTTOM PLATE
TOP CABINET : Remove 4 screws 1.
FRONT PANEL : Remove 2 screws 2and 7 clips
3.Remove button 4.
JOG SWITCH : Remove 3 screws u.
JACK PWB : Remove 1 screw 5and 1 hook 6.
FRONT PWB : Remove 1 connector 7and 3 hooks
8.
OPERATION PWB : Remove 1connector 9and 3 hooks
0.
PWB HOLDER : Remove 3 screws q.
MECHANISM/ : Remove 1 screw wand Shield Angle.
MAIN PWB UNIT Remove 2 screws eand 4screws
r.
ANTENNA : Remove 2 Screws t.
TERMINAL
COVER
BOTTOM PLATE : Remove 6 screw y.
OPERATION
PWB
JOG SWITCH

5
VC-H800X
1. When removing the mechanism from the main PWB,
removetheantennacover1screw1,andremovethe
antenna cover.
Remove the PWB bottom plate 1 screw 2.
Remove the FFC cable (AA, AD, AH) 3which con-
necting the PWB and the mechanism.
Take out vertically the mechanism so that it does not
damage the adjacent parts.
2. Removing the mechanism and cassette housing.
Remove2screws4fixingthecassettehousingtothe
mechanism, and remove the cassette housing.
MECHANISM CHASSIS
2
1
3
4
CASSETTE
HOUSING
MAIN PWB
2-2 DISASSEMBLING THE MECHANISM/MAIN PWB ASSEMBLY

6
VC-H800X
cassette housing. (Conditions: When mechanism and
PWB have been installed)
2. Mechanical initial setting
Feed the pulley feed gear of loading motor with screw
driver. After ascertaining the return to the initial set posi-
tion (*1) install the cassette housing in the specified
position.(Thismethodisappliedonlyforthemechanism.)
Pulley feed gear
Screwdriver
Casecon
drive gear
Drive angle of
cassette housing
Tilt mark (*1)
INSTALLING THE CASSETTE HOUSING
Whenthecassettehousingisinstalledonthemechanism,
the initial setting is essential condition.
There are two initial setting methods, namely electrical
and mechanical.
1. Electrical initial setting
So as to perform initial setting of mechanism execute the
Step1 of Installation ofcassettehousing. After ascertain-
ing the return to the initial setting position (*1) install the
2-3 CARES WHEN REASSEMBLING
START SENSOR
PARTS WHICH NEED PARTICULAR CARE
Wheninstalling the mechanismchassis on thePWB unit,
take care so as to prevent deformation due to contact of
mechanism chassis with REC TIP SW.
AE CONNECTOR
AL CONNECTOR
REC TIP SW
END SENSOR
AC CONNECTOR
INSTALLING THE MECHANISM ON PWB
Lower vertically the mechanism, paying attention to the
mechanism edge, and install the mechanism with due
care so that the parts are not damaged. So as to fix the
mechanismtothemain PWBinstalltwohousings. (Fitthe
antenna cover to one of them. For other, fix the vicinity of
loading motor and solder joint side of main PWB.) Con-
nect again the FFC cable (AA-MH, AD-ME, AH-MH)
between the mechanism and the main PWB.

7
VC-H800X
3. FUNCTION OF MAJOR MECHANICAL PARTS (TOP VIEW)
1715 10
11
5
9
14
12
8
16
13
4
6
2
7
3
1
18
No. Function No. Function
1 Full erase head
2 Supply pole base ass’y
3 Tension arm ass’y
4 Idler wheel ass’y
5 Pinch drive lever ass’y
6 Supply reel disk
7 Supply main brake ass’y
8 Take-up main brake ass’y
9 Pinch drive cam
10 A/C Head ass’y
11 Reverse guide lever ass’y
12 Casecon drive gear
13 Take-up reel disk
14 Pinch roller lever ass’y
15 Drum ass’y
16 Loading motor
17 Drum motor
18 Take-up pole base ass’y

8
VC-H800X
FUNCTION OF MAJOR MECHANICAL PARTS (BOTTOM VIEW)
26
24
21
22
19
20
12
23
No. Function No. Function
19 Slow brake
20 Master cam
21 Capstan D.D. motor
22 Reel belt
23 Clutch lever
24 Limiter pulley ass'y
12 Casecon drive gear
26 Shifter

9
VC-H800X
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.
4-1 MECHANISM CONFIRMATION ADJUSTMENT JIG
So as to perform completely the mechanism adjustment prepare the following special jigs. So as to maintain the initial
performance of the machine the maintenance and check are necessary. Utmost care must be taken so that the tape is
not damaged. If adjustment needs any jig, be sure to use the required jig.
JiGTG1200 CN
JiGMP0001 BY
1. Torque Cassette Meter JiGVHT-063 CZ
No. Jig ltem Part No. Code Configuration Remarks
JiGTG0090 CM
3. Torque Gauge Head JiGTH0006 AW
5. JiGRH0002 BR
JiGSG2000 BS
JiGSG0300 BF
6.
7. JiGADP003 BK
2. Torque Gauge
Tension Gauge
These Jigs are used for checking
and adjusting the reel disk height.
Whenfixinganyparttothethreaded
hole using resin with screw, use the
jig. (Specified torque 5 kg)
Thiscassettetorquemeterisusedforcheck-
ing and adjusting the torque of take-up for
measuring tape back tension.
These Jigs are used for checking
and adjusting the torque of take-up
and supply reel disks.
Master Plane Jig and
Reel Disk Height
Adjusting Jig
Pinch pressing force
measuring jig
This Jig is used with the tension
gauge.Rotarytransformerclearance
adjusting jig.
There are two gauges used for the
tension measurements, 300 g and
2.0kg.
4. Torque Driver JiGTD1200 CB
9. JiGDRiVER11055 AR
Reverse guide height
adjusting box driver This Jig is used for height adjustment of the
reverse guide (for reverse guide height ad-
justment).
Guide roller height
adjustment drive This screwdriver is used for adjusting the
guide roller height.
For X value adjustment
X value adjustment
gear type screw driver
This Jig is used for height
adjustment of the reverse guide.
13. JiGRVGH-F18 BU
12. JiGDRiVER-6 BM
Reverse Guide Height
Adjusting Jig
11. JiGDRiVERH-4 AP
10. Alignment Tape VROCPSV CK

10
VC-H800X
Video head cleaning procedure
1. Apply one drop of cleaning liquid to the cleaning paper with the baby oiler.
2. Gentlypressthecleaningpaperagainstthe videoheadtofixyourfinger,and movetheupperdrumsothateachhead
is passed to and from 5 times (do not move the cleaning paper).
3. Wipe with the dry cleaning paper.
Notes :
• Use the commercially available ethanol of Class 1 as
cleaning liquid.
• Since the video head may be damaged, do not move up
and down the cleaning paper.
• Whenever the video head is cleaned, replace the clean-
ing paper.
• Do not apply this procedure for the parts other than the
video head.
Parts Code Description Code
ZPAPRA56-001E Cleaning Paper AW
ZOiLR-02-24TE Babe Oiler (Spoit) AH
Gently press the cleaning paper to
fix with your finger, and rotate the
upper drum to clean.
Move to and from 5 times for each head.
(Do not move the cleaning paper.)
Rotate the upper drum
with one hand.
NOTE : Part replacement. : Cleaning : Apply grease
<Specified> Cleaning liquid Industrial ethyl alcohol
* This mechanism does not need electric adjustment with variable resistor. Check parts. If any deviation is found,
clean or replace parts.
Maintained
Parts Remarks
500
hrs. 1000 hrs. 1500 hrs. 2000 hrs. Possible symptom
encountered
Guide roller ass’y
Sup guide shaft
Reverse guide
Slant pole on pole base
Full erase head
A/C head
Upper and lower drum ass’y
Capstan D.D. motor
Pinch roller
Reel belt
Tension band ass’y
Loading motor
Idler ass’y
Limiter pulley
Supply/take-up main brake levers
AHC (Automatic Head Cleaner)
color and beating
Small sound or sound
distortion
Poor S/N ratio, no color
Poor flatness of the
envelope with alignment
tape
No tape running,
uneven color
No tape running, tape
slack
No tape running, tape
slack, no fast forward/
rewind motion
Lateral noises Head
occasionally blocked
Abnormal rotation or significant
vibration requires replacement.
Clean tape contact part with the
specified cleaning liquid.
Clean tape contact area with the
specified cleaning liquid.
Clean rubber and rubber contact
area with the specified cleaning
liquid.
Replace the roller of the cleaner
when it wears down.
Just change the AHC roller
assembly for new one.
Screen swaying
Cassette not loaded or
unloaded
No tape running, tape
slack
Tape slack
MAINTENANCE CHECK ITEMS AND EXECUTION TIME
Perform the maintenance with the regular intervals as follows so as to maintain the quality of machine.