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VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
SERVICE MANUAL
S99N9VC-A230N
VIDEO CASSETTE RECORDER
(VC-A230NZ/X)
(VC-A280NZ/X,A480NZ/X)
VC-A230NZ/X VC-A280NZ/X MODEL VC-A480NZ/X
In the interests of user-safety (Required by safety regulations in some countries) the set should be restored to its original condition and only parts identical to those specified be used.
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. ELECTRICAL TROUBLESHOOTING ................................................................................. 38 8. BLOCK DIAGRAM ............................................................................................................... 49 9. SCHEMATIC DIAGRAM AND PWB FOIL PATTERN ......................................................... 57 10. REPLACEMENT PARTS LIST ............................................................................................ 71 11. EXPLODED VIEW OF MECHANISM PARTS ..................................................................... 78 12. PACKING OF THE SET ...................................................................................................... 82
SHARP CORPORATION 1
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
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: IC901
Refer to the symbol on the PWB and the anode marking of the part.
(3) Cam switches A and B: D708 and D705.
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: D711 and D712.
Be careful not to confuse the setting direction of the parts in reference to the symbols on the PWB. Do not allow any looseness.
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VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
1. SPECIFICATIONS
Format: Video recording system: Video signal: Recording/playing time: VHS PAL/NTSC standard Rotary, slant azimuth two heads helical scan system PAL colour or monochrome (CCiR system B/G) signals 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) 12.7mm 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) 75 ohm unbalanced VHF Channel NZ1 - NZ11, UHF Channel E21 - E69(VC-A230NZ/A280NZ/A480NZ) VHF Channel AU0 - AU12, UHF Channel AU28 - AU69(VC-A230X/A280X/A480X) UHF Channel E21 - E69 Adjustable preset to E3(VC-A230NZ/A280NZ/A480NZ) UHF Channel AU28 - AU69 Adjustable preset to AU37(VC-A230X/A280X/A480X) AC230V ± 15%(NZ) ,AC240V ± 10%(X) , 50Hz Approx. 16W 5°C to 40°C 20°C to 55°C Approx. 2.9 kg 360 mm (W) x 256 mm (D) x 92 mm (H)
Tape width: Tape speed:
Antenna: Receiving channel: RF converter output signal: Power requirement: Power consumption: Operating temperature: Storage temperature: Weight: Dimensions: VIDEO Input: Output: S/N ratio: Horizontal resolution: AUDIO Input: Output: S/N ratio: Frequency responce:
1.0 Vp-p, 75 ohm 1.0 Vp-p, 75 ohm 45 dB (PAL-SP) 250 lines (PAL-SP) 0 dBs = 0.775 Vrms Line -8 dBs/47k ohm Line -8 dBs/1k ohm 43 dB (SP mode) 80 Hz ~ 10 kHz (SP mode) 80Hz ~ 5Hz (LP/EP mode) Accessories included: 75 ohm coaxial cable Operation manual Infrared remote control Guarantee Card Battery As part of our policy of continuous improvement, we reserve the right to alter design and specifications without notice. Note: The antenna must correspond to the new standard DIN 45325 (IEC 169 - 2) for combined UHF/VHF antenna with 75 ohm connector.
3
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
2. DISASSEMBLY AND REASSEMBLY
2-1 DISASSEMBLY OF MAJOR BLOCKS
TOP CABINET FRONT PANEL : Remove 2 screws 1. : Remove button and knob 2. Remove 2 screws 3 and 7 clips 4. : Remove 2 screws 5. : Remove 1 screw 6.
TOP CABINET
1
PWB HOLDER OPERATION PWB SHIELD ANGLE : Remove 1 screws 7 with shield angle. MECHANISM/ : Remove 1 screw 8, 1 screw 9, 2 MAIN PWB screws 0, 2 screws q. Remove 1 screw w with antenna terminal cover. Remove 1 screw e with top cabinet fix angle.
SHIELD ANGLE
7 3 11 3
C H/A SHIELD
TOP
A
ANTENNA TERMINAL COVER
10
B
12
MECHANISM/ MAIN PWB ASSEMBLY
A
5
PWB HOLDER
8
TOP CABINET FIX ANGLE
13
C B
MAIN FRAME FRONT PANEL
9
4
6
OPERATION PWB
2
4
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
2-2 DISASSEMBLING THE MECHANISM/MAIN PWB ASSEMBLY
1. When removing the mechanism from the main PWB, remove the antenna cover 1 screw 1, and remove the antenna cover. Remove the PWB bottom plate 1 screw 2. Remove the FFC cable (AA, AD, AH) 3 which connecting 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. Remove 2 screws 4 fixing the cassette housing to the mechanism, and remove the cassette housing.
4
MECHANISM CHASSIS
1
CASSETTE HOUSING
3
MAIN PWB
2
5
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
2-3 CARES WHEN REASSEMBLING
INSTALLING THE CASSETTE HOUSING When the cassette housing is installed on the mechanism, 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 Step 1 of Installation of cassette housing. After ascertaining the return to the initial setting position (*1) install the
Pulley feed gear Casecon drive gear
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 position (*1) install the cassette housing in the specified position. (This method is applied only for the mechanism.)
Screwdriver
Tilt mark (*1)
Drive angle of cassette housing
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 mechanism to the main PWB install two housings. (Fit the antenna cover to one of them. For other, fix the vicinity of loading motor and solder joint side of main PWB.) Connect again the FFC cable (AA-MH, AD-ME, AH-MH) between the mechanism and the main PWB.
PARTS WHICH NEED PARTICULAR CARE When installing the mechanism chassis on the PWB unit, take care so as to prevent deformation due to contact of mechanism chassis with REC TIP SW.
AE CONNECTOR END SENSOR
REC TIP SW
AC CONNECTOR
START SENSOR AL CONNECTOR
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VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
3. FUNCTION OF MAJOR MECHANICAL PARTS (TOP VIEW)
15
17
18
10
14 1 9 2 7 11 5
3
12 8
16 6 4 13
No. 1 2 3 4 5 6 7 8 9 10 Full erase head
Function
No. 11 12 13 14 15 16 17 18
Function Reverse guide lever ass'y Casecon drive gear Take-up reel disk Pinch roller lever ass'y Drum ass'y Loading motor Drum motor Take-up pole base ass'y
Supply pole base ass'y Tension arm ass'y Idler wheel ass'y Pinch drive lever ass'y Supply reel disk Supply main brake ass'y Take-up main brake ass'y Pinch drive cam A/C Head ass'y 7
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
FUNCTION OF MAJOR MECHANICAL PARTS (BOTTOM VIEW)
21 22 19 20 26
12
23
24
No. 19 20 21 22 Slow brake Master cam
Function
No. 23 24 12 26 Clutch lever
Function
Limiter pulley ass'y Casecon drive gear Shifter
Capstan D.D. motor Reel belt
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VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
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. No. 1. Jig ltem Torque Cassette Meter Part No. JiGVHT-063 JiGTG0090 2. Torque Gauge JiGTG1200 3. Torque Gauge Head JiGTH0006 CN AW When fixing any part to the threaded hole using resin with screw, use the jig. (Specified torque 5 kg) These Jigs are used for checking and adjusting the reel disk height. There are two gauges used for the tension measurements, 300 g and 2.0kg. This Jig is used with the tension gauge. Rotary transformer clearance adjusting jig.
This Jig is used for height adjustment of the reverse guide (for reverse guide height adjustment).
Code CZ CM
Configuration
Remarks
This cassette torque meter is used for checking 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.
4.
Torque Driver Master Plane Jig and Reel Disk Height Adjusting Jig Tension Gauge
JiGTD1200 JiGRH0002 JiGMP0001 JiGSG2000
CB BR BY BS BF BK AR CK
5.
6.
JiGSG0300 7. 9. Pinch pressing force measuring jig Reverse guide height adjusting box driver JiGADP003 JiGDRiVER11055 VROCPSV 10. Alignment Tape VROUBZFS (VC-A230NZ/X, A280NZ/X)
11. adjustment drive X value adjustment 12. gear type screw driver 13. Reverse Guide Height Adjusting Jig
Guide roller height
JiGDRiVERH-4 AP JiGDRiVER-6 JiGRVGH-F18 BM BU
This screwdriver is used for adjusting the guide roller height.
For X value adjustment
This Jig is used for height adjustment of the reverse guide.
9
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
Parts 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 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 Screen swaying Cassette not loaded or unloaded No tape running, tape slack Tape slack Replace the roller of the cleaner when it wears down. Just change the AHC roller assembly for new one. Lateral noises Head occasionally blocked Maintained 500 1000 1500 2000 hrs. hrs. hrs. hrs. Possible symptom encountered Remarks 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.
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)
Clean rubber and rubber contact area with the specified cleaning liquid.
NOTE : Part replacement. : Cleaning : Apply grease 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.
Video head cleaning procedure 1. Apply one drop of cleaning liquid to the cleaning paper with the baby oiler. 2. Gently press the cleaning paper against the video head to fix your finger, and move the upper drum so that each head is passed to and from 5 times (do not move the cleaning paper). Rotate the upper drum 3. Wipe with the dry cleaning paper. with one hand. 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 cleaning paper. · Do not apply this procedure for the parts other than the video head.
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.)
Parts Code ZPAPRA56-001E ZOiLR-02-24TE
Description Cleaning Paper Babe Oiler (Spoit)
Code AW AH
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VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
REMOVING AND INSTALLING THE CASSETTE HOUSING
· Removal 1. In the cassette removing mode, remove the cassette. 2. Unplug the power cord. 3. Remove in the following numerical order. a) Remove two screws 1. b) Slide and pull up the cassette housing control.
1
Notes: 1. When fitting the S/E sensor holder to the cassette controller frame L/R, take care. 2. Misengagement of teeth of casecon drive gear and drive angle gear causes malfunction. (The cassette cannot be set, load and ejection are repeated). 3. In the case when you use the magnet screw driver, never approach the magnet driver to the A/C head, FE head, and drum. 4. When installing or removing, take care so that the cassette housing control and tool do not contact the guide pin or drum. 5. After installing the cassette housing control once perform cassette loading operation.
TO RUN A TAPE WITHOUT THE CASSETTE HOUSING CONTROL ASSEMBLY
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Figure 4-1. · Reassembly 1. Before installing the cassette housing control, shortcircuit TP801 provided at the center (when facing to the main PWB), press the eject button. The casecon drive gear turns and stops when the positioning mark appears. Engage two teeth of casecon drive gear with the three teeth of casecon drive angle gear, and set on the mechanism chassis as shown below. Remove the full-surface panel. Short-circuit TP801. Plug in the power cord. Turn off the power switch. (The pole bases move into U.L.position.) Open the lid of a cassette tape by hand. Hold the lid with two pieces of vinyl tape. Set the cassette tape in the mechanism chassis. Stabilize the cassette tape with a weight (500g) to prevent floating. Turn on the power switch. Perform running test.
500g
Weight to prevent float (500g)
Mechanism chassis
Figure 4-3. Note: The weight should not be more than 500g.
Casecon drive angle gear
Casecon drive gear
To take out the cassette tape. 1. Turn off the power switch. 2. Take out the cassette tape.
Figure 4-2. 2. Install in the reverse order of removal. 11
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
REEL DISK REPLACEMENT AND HEIGHT CHECK
Removal Remove the cassette housing control assembly. Pull the tension band out of the tension arm ass'y. Remove the Supply/Take-up main brake ass'y. Open the hook at the top of the reel disk, and remove the reel disk. Note: Take care so that the tension band ass'y and main brake ass'y (especially soft brake) are not deformed.
Tension arm ass'y
· 1. 2. 3. 4.
4. Assemble the Supply main brake ass'y. Notes: 1. When installing the reel disk, take due care so that the tension band ass'y is not deformed and grease does no adhere. 2. Do not damage the Supply main brake ass'y. Be careful so that grease does not adhere to the brake surface. · Reassembly (Take-up reel disk) 1. Clean the reel disk shaft and apply grease (SC-141) to it. 2. Align the phase of the reel disk to that of the reel relay gear and to install a new take-up reel disk onto the shaft. 3. Check the reel disk height and reassemble the take-up main brake ass'y. Note: 1. Take care so that the Take-up main brake ass'y is not damaged. Take care so that grease does not adhere the brake surface. 2. After reassembly, check the video search rewind back tension (see page 15), and check the brake torque (see page 17). · Height checking and adjustment Note: 1. Set the master plane with due care so that it does not contact the drum. 2. When putting the master plane, shift the reverse guide a little in the loading direction. Care must be taken since excessive shift results in damage.
Take-up main brake Supply main brake ass'y
Tension band ass'y
ass'y
Supply reel disk
Take-up reel disk Master plane Reverse
Figure 4-4. Note: When the tension band ass'y is pressed in the direction of the arrow for removal, the catch is hard to be deformed.
Take-up reel disk Supply reel disk Cassette lock release shaft guide Position pin
Figure 4-6. Note: · Check that the reel disk is lower than part A but higher than part B. If the height is not correct, readjust the reel disk height by changing the poly-slider washer under the reel disk.
Figure 4-5. · Reassembly (Supply reel disk) 1. Clean the reel disk shaft and apply grease (SC-141) to it. 2. Match the phases of reel disk and reel relay gear, and set the new reel disk. 3. After checking the reel disk height, wind the tension band ass'y around the reel disk, and insert into the hole of tension arm ass'y. 12
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X Note: Whenever replacing the reel disk, perform the height checking and adjustment.
Master plane Reel disk height adjusting jig Mechanism chassis
Notes: 1. Hold the torque gauge by hand so that it is not moved. 2. Do not keep the reel disk in lock state. Do not allow longtime measurement.
10 ± 0.2mm
Reel disk
CHECKING AND ADJUSTMENT OF TAKE-UP TORQUE IN REWIND MODE
· Remove the cassette housing control assembly. · After short-circuiting TP801 provided at the center (facing to the main PWB), plug in the power cord. · Setting 1. Set a torque gauge to zero on the scale. Place it on the supply reel disk. 2. Press the rewind button. 3. To calculate the remaining capacity, slowly rotate the take-up reel disk, and then shift it into the rewind mode. · Checking 1. Turn the torque gauge slowly (one rotation every 2 to 3 seconds) by hand in the CCW direction. 2. Make sure that the indication of torque gauge is not less than 30mN·m (306gf·cm).
Torque gauge
A
Reel disk
B
Figure 4-7.
CHECKING AND ADJUSTMENT OF TAKE-UP TORQUE IN FAST FORWARD MODE
· Remove the cassette housing control assembly. · After short-circuiting TP801 provided at the center (facing to the main PWB), plug in the power cord. · Setting 1. Set a torque gauge to zero on the scale. Place it on the take-up reel disk. 2. Press the FF button. 3. To calculate the remaining capacity of the play back mode, slowly rotate the supply reel disk, and then shift it into the forward mode. · Checking 1. Turn the torque gauge slowly (one rotation every 2 to 3 seconds) by hand in the CW direction. 2. Make sure that the indication of torque gauge is not less than 30mN·m (306gf·cm).
Torque gauge
30mN·m (306gf·cm) or more CCW
The gauge is held at its maximum value. (Red mark)
Supply reel disk 30mN·m (306gf·cm) or more CW
The gauge is held at its maximum value. (Red mark)
Idler ass'y
Figure 4-9. · Adjustment 1. If the rewind winding-up torque is less than the specified value, clean the capstan D.D. motor pulley, drive belt, and limiter pulley with cleaning liquid, rewind again, and check the winding-up torque. 2. If the winding-up torque is still out of range, replace the drive belt.
Idler ass'y
Figure 4-8. · Adjustment 1. If the FF winding-up torque is less than the specified value, clean the capstan D.D. motor pulley, reel belt, and limiter pulley with cleaning liquid, and check again. 2. If the torque is less than the set value, replace the reel belt.
13
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X Notes: 1. Hold the torque gauge by hand so that it is not moved. 2. Do not keep the reel disk in lock state. Do not allow longtime measurement.
CHECKING AND ADJUSTMENT OF TAKE-UP TORQUE IN VIDEO SEARCH REWIND MODE
· Remove the cassette housing control assembly. · After short-circuiting TP801 provided at the center (facing to the main PWB), plug in the power cord. · Setting Press the playback button and rewind button to set the video search rewinding mode. · Checking Place the torque gauge on the supply reel disk, and turn it counterclockwise very slowly (one rotation every 1 to 2 seconds) and check that the torque is within the set value 14.0 ± 3.9mNm. (144 ± 40gfcm)
Torque gauge
CHECKING AND ADJUSTMENT OF TAKE-UP TORQUE IN RECORD/PLAYBACK MODE
· Remove the cassette housing control assembly. · After short-circuiting TP801 provided at the center (facing to the main PWB), plug in the power cord. · Turn off the power switch. · Open the cassette torque meter lid, and fix it with tape. · Load the cassette torque meter into the unit. · Put the weight (500g) on the cassette torque meter. · Turn on the power switch. · Press the REC button, and set LP picture record mode.
Set value LP6.9 ± 2.5mNm (70 ± 25gfcm)
CCW
500g
Cassette torque meter Supply reel disk
Figure 4-10. · Checking 1. Make sure that value is within the setting 6.9±2.5mN·m (70±25gf·cm). 2. The winding-up torque fluctuates due to variation of rotation torque of limiter pulley ass'y. Read the center value of fluctuation as setting. 3. Set the LP record mode and make sure that the windingup torque is within setting. · Adjustment If the playback winding-up torque is not within the setting, replace the limiter pulley assembly. Note: When the torque cassette is set, put a weight (500g) to prevent rise. When the cassette torque meter is taken out. Turn off the power switch. Figure 4-11.
Note: Surely put the torque gauge on the reel disk to measure. If the torque gauge is raised, accurate measurement is impossible. · Adjustment If the rewinding playback winding-up torque is not within the setting, replace the limiter pulley assembly. Note: The winding-up torque fluctuates due to variation of rotation torque of supply reel disk. Read the center value of fluctuation as setting.
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VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
CHECKING THE VIDEO SEARCH REWIND BACK TENSION
· Remove the cassette housing control assembly. · After short-circuiting TP801 provided at the center (facing to the main PWB), plug in the power cord. · Checking 1. After pressing the play button, press the rewind button, and set the video search rewind mode. 2. Place the torque gauge on the take-up reel disk, and turn it counterclockwise very slowly (one rotation every 2 to 3 seconds) and check that the torque is within the set value 3.4±1.5mNm (35±15gfcm).
Torque gauge Pinch roller Tension gauge 8.8 ~ 11.8 N (900 - 1,200gf)
Capstan shaft Tension gauge adapter
Figure 4-13. 1. Detach the pinch roller from the capstan shaft. Do not separate excessively. Or the pinch lever and pinch double action lever may disengage. 2. Engage the tension gauge adapter with the pinch roller shaft, and pull in the arrow direction. 3. Gradually return the pinch roller, and measure the pulling force when the pinch roller contacts the capstan shaft. 4. Make sure that the measured value is within setting 8.8 to 11.8 N (900 to 1,200gf).
CCW
Take-up reel disk
CHECKING AND ADJUSTMENT OF TENSION POLE POSITION
Figure 4-12. Notes: Set the torque gauge securely on the take-up reel disk. If it is not secure, the measurement will be incorrect. · Remove the cassette housing control assembly. · After short-circuiting TP801 provided at the center (facing to the main PWB), plug in the power cord. · 1. 2. 3. 4. 5. 6. Setting Turn off the power switch. Open the cassette tape (E-180), and fix with tape. Set the cassette tape in loading state. Put the weight (500g) on the cassette tape. Turn on the power switch. Make the adjustment with the beginning of a E-180 tape.
(E-180)
CHECKING THE PINCH ROLLER PRESSURE
· Remove the cassette housing control assembly. · After short-circuiting TP801 provided at the center (facing to the main PWB), plug in the power cord.
· Checking Press the play button to set the playback mode.
500g
Weight to prevent float (500g)
Figure 4-14. · Checking 1. Set a cassette tape, push the REC button to place the unit in the SP record mode. Now check the tension pole position. 15
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X 2. Visually check to see if the right edge of the tension pole is within the 2.3 ± 0.25 mm from the right edge of the Sup guide shaft.
Tension pole adjuster adjusting range
Tension pole adjuster
Sup guide shaft Tension pole
90°
2.3 ± 0.25
90°
Make the adjustment with the beginning of a E-180 tape.
Figure 4-18. Adjust so that the delta mark of tension pole adjuster is within 90° range (left, right).
Figure 4-15. At left side from the center line
CHECKING AND ADJUSTMENT OF RECORD/ PLAYBACK BACK TENSION
· Remove the cassette housing control assembly. · After short-circuiting TP801 provided at the center (facing to the main PWB), plug in the power cord.
2.3 ± 0.25
Figure 4-16. Insert the slotted screwdriver in the tension pole adjuster, and rotate counterclockwise. At right side from the center line
· 1. 2. 3. 4. 5.
Setting Turn off the power switch. Open the torque cassette meter and fix with tape. Set the cassette tape in loading state. Put the weight (500g) on the cassette torque meter. Turn on the power switch.
500g
Weight to prevent float (500g) Cassette torque meter
2.3 ± 0.25
Figure 4-19. · Checking 1. Push the REC button to place the unit in the SP record mode. 2. At this time ascertain that the back tension is within the setting (36.5 to 52g·cm) by seeing the indication of torque cassette meter.
Figure 4-17. Insert the slotted screwdriver in the tension pole adjuster, and rotate clockwise.
16
· Adjustment 1. If the indication of torque cassette meter is lower than the setting, shift the tension spring engagement to the part A. 2. If the indication of torque cassette meter is higher than the setting, shift the tension spring engagement to the part B.
A Tension arm B
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X · Checking the brake torque at the take-up side
Torque gauge
CW Take-up reel disk
CCW
Tension spring
Figure 4-20.
CHECKING THE BRAKE TORQUE
· Checking the brake torque at the supply side
CCW: 4.9~13.7mNm (50~140gfcm) CW: 3.9~10.8mNm (40~110gfcm)
Figure 4-22. · Remove the cassette housing control assembly.
Torque gauge CCW CW
· After short-circuiting TP801 provided at the center (facing to the main PWB), plug in the power cord. · 1. 2. 3. Setting Switch from the FF mode to the STOP mode. Disconnect the power cord. Set a torque gauge to zero on the scale. Place it on the take-up reel disk.
Supply reel disk
CCW: 2.9~9.8mNm (30~100gfcm) CW: 4.9~13.7mNm (50~140gfcm)
Figure 4-21. · Remove the cassette housing control assembly. · After short-circuiting TP801 provided at the center (facing to the main PWB), plug in the power cord. · Setting 1. Set a torque gauge to zero on the scale. Place it on the supply reel disk. 2. Switch from the FF mode to the STOP mode. 3. Disconnect the power cord. · Checking Turn the torque gauge at a rate of about one turn/2 sec in the CW direction/CCW direction with respect to the supply reel disk so that the reel disk and torque gauge pointer rotate at equal speed, and make sure that the value is within the setting (CW direction: 4.9 to 13.7mN·m (50 to 140gf·cm); CCW direction: 2.9 to 9.8mN·m (30 to 100gf·cm).
· Checking 1. Turn the torque gauge at a rate of about one turn/2 sec in the CCW direction/CW direction so that the reel disk and torque gauge pointer rotates at equal speed and make sure that the value is within the setting (CCW direction: 4.9 to 13.7mN·m (50 to 140gf·cm), CW direction: 3.9 to 10.8 mN·m (40 to 110gf·cm). 2. Adjustment of the brake torque at the supply side and the take-up side · Unless the supply side brake torque or take-up side brake torque is within the setting, clean the felt surface of reel disk (supply, take-up) brake lever, check again the brake torque. · If value cannot be set within the setting yet, replace the main brake ass'y or main brake spring.
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VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
REPLACEMENT OF A/C (Audio/Control) HEAD
1. Remove the cassette housing control assembly. 2. In unloading state unplug the power cord. · Removal 1. Remove the screws 123, Azimuth screw, Tilt screw. 2. Unsolder the PWB fitted to the A/C head. Notes: 1. When replacing, never touch the head. If you touched, clean with the cleaning liquid. 2. When removing the screw 3, take care so that the spring may out.
3. Align the left end of gear of A/C head plate with the punched mark of chassis, tentatively tighten the screws 1 and 2 so as to ensure smooth motion of A/C head plate. Tentative tightening torque must be 0.15 to 0.20 N·m (1.5 to 2.0kgf·cm).
1
3
Height screw Left end of A/C head plate gear Punched line mark on chassis
2 3 Tilt screw Azimuth screw
Height screw Spring 1
Figure 4-25. Note: 1. If the screws 1 and 2 are tighten tentatively too loose, the azimuth and height of A/C head may change when they are finally tightened. Therefore care must be taken. 2. After completion of A/C head be sure to adjust tape running. (Execute the running adjustment by the method described in Page 20, 21.)
2
Figure 4-23.
· Replacement 1. Solder the removed PWB to the new head assembly. 2. Adjust the height from the A/C head plate (lower surface) to the A/C head base to 10.8mm with slide calipers. (3 places of azimuth screw section, tilt screw section and hight screw section) (See the figure below.)
Solder New A/C head ass'y A/C head PWB gNever touch the head A/C head base
10.8mm
10.8mm
Figure 4-24. 18
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
A/C HEAD HEIGHT ROUGH ADJUSTMENT
· Setting
Azimuth screw
HEIGHT ADJUSTMENT OF REVERSE GUIDE
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. (Refer to Figure 4-28 (a) (b).)
Reverse guide height adjusting jig
Reverse guide Reverse guide height adjusting jig Height screw Tilt screw
Cassette tape
Mechanism chassis
13.38mm
(a)
500g
(b) Figure 4-28.
Weight to prevent float (500g)
Mechanism chassis
2. Rotate counterclockwise the reverse guide height adjustment nut 1/10 turn. (For height adjustment use the reverse guide height adjustment box driver (JiGDRiVER 11055)).
Figure 4-26.
Box driver
1. Set the cassette tape in the unit. 2. Press the PLAY button to put the unit in the playback mode. 3. Roughly adjust the height of the A/C head by turning the height screw until the tape is in the position shown below.
A/C head
CCW
Height adjusting nut
Tape 0.3mm
Figure 4-29. 3. Set the tape, and check for tape crease near the reverse guide in the playback mode. If crease is found, turn the reverse guide adjustment nut to remove crease. (As for crease check refer to Figure 430.) A Capstan
motor shaft
500g
Figure 4-27. · Adjustment Adjust the height screw visually so that the control head is visible 0.3mm below the bottom of the tape.
Fixing guide Mechanism chassis Reverse guide
Weight to prevent float (500g)
An example of crease near the reverse guide
* Check for crease from the A direction. Figure 4-30.
19
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
ADJUSTMENT OF TAPE DRIVE TRAIN
1. Tape run rough adjustment 1 Remove the cassette housing control assembly. 2 After shortcircuiting TP801 provided at the center (facing to the main PWB), plug in the power cord. 3 Check and adjust the position of the tension pole. (See page 15.) 4 Check and adjust the video search rewind back tension. (See page 15.) 5 Connect the oscilloscope to the test point for PB CHROMA envelope output (TP201). Set the synchronism of the oscilloscope to EXT. The PB CHROMA signal is to be triggered by the head switching pulse (TP202). 6 Set the alignment tape (VROCPSV) to play. (Put a 500g weight on the cassette tape to prevent lift of cassette tape.)
Guide roller Cassette Tape
Notes: 1. Previously set the tracking control in the center position, and adjust the envelop waveform to maximum with X value adjustment nut. Thereby the tape run rough adjustment is facilitated. 2. Especially the outlet side envelope waveform must have higher flatness.
500g
Weight of 500g
Figure 4-31. 7 Press the tracking button (+), () and change the envelope waveform from max to min and from min to max. At this time make sure that the envelope waveform changes nearly parallel. 8 Unless the envelope waveform changes nearly parallel, adjust the height of supply side and take-up side guide roller so that the envelope waveform changes nearly parallel. (For envelop adjustment procedure refer to Figure 4-35.) 9 Turn the tilt screw to remove the tape crease at the fixing guide flange. Playback the tape and check for tape crease at the fixing guide flange. (1) If there is no tape crease Turn the tilt screw clockwise so that tape crease appears once at the flange, and then return the tilt screw so that the crease disappears. (2) If there is tape crease Turn counterclockwise the tilt screw so that the tape crease disappears. (Reference) If the tilt screw is turned clockwise crease appears at the lower flange.
Figure 4-32. 2. Adjustment of A/C head height and azimuth 1 Perform the initial setting of A/C head position by the method stated in "Page 18 Replacement 3". 2 Connect the oscilloscope to the audio output terminal. 3 Using the alignment tape in which 1 kHz linear audio signal has been recorded, adjust the height screw so as to get max audio output. 4 Using the alignment tape in which 6 kHz linear audio signal has been recorded, adjust the azimuth screw so as to get max audio output. 5 Repeat the above adjustment steps 3 and 4 a couple of times. Finally take the step 4 again.
For X value adjustment Adjust the X value, turning the geartype screwdriver.
Figure 4-33. 3. Tape run adjustment 1 Connect the oscilloscope to PB CHROMA envelope output test point, set oscilloscope sync to EXT, trigger-input the PB CHROMA signal (head switching pulse). 2 Rough adjustment of X value Tentatively fix A/C head arm screws 1 and 2 by the method described in Page 18 "Replacement 3". Playback the alignment tape (Use VROUBZFS for VC-A230NZ/X,A280NZ/X) and shortcircuit TP802. As a result the auto-tracking is automatically cancelled, so that the X value adjustment mode is set. Move the A/C head with the X value adjustment gear driver (JiGDRiVER-6) by the method shown in Figure 4-33, and adjust the A/C head so as to get the maximum envelope waveform. (Note: When the A/ C head is adjusted, adjust so that the maximum envelop waveform is obtained nearest the position of initial setting made in Page 18.)
20
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X 3 Next, 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 and take-up side guide roller with the adjustment driver (JiGDRiVERH-4) so that the envelope waveform changes nearly parallel. 4 If the tape is lifted or sunk from the helical lead surface, the PB CHROMA envelope waveform appears as shown in Figure 4-35. 5 Press the tracking button (+), () and make sure that the envelope waveform changes nearly parallel. 6 Finally check tape crease near the reverse guide. If tape crease is found, remove it as stated in Page 19 "HEIGHT ADJUSTMENT OF REVERSE GUIDE" item 3.
PB CHROMA Envelope
CH-1
CH-2
Head switching pulse Figure 4-34. 4. A/C head X value adjustment 1 Tentatively fix A/C head arm screws 1 and 2 by the method described in Page 18 "Replacement 3". 2 Playback the alignment tape (Use the VROUBZFS for VC-A230NZ/X,A280NZ/X) and shortcircuit TP802. As a result the auto-tracking is automatically cancelled, so that the X value adjustment mode is set. 3 Move the A/C head with the X value adjustment gear When the tape is below the helical lead. Supply side Take-up side
When the tape is above the helical lead. Supply side Take-up side
Adjustment
Supply side guide roller rotated in clockwise direction (lowers guide roller) to flatten envelope.
Take-up side guide roller rotated in clockwise direction (lowers guide roller) to flatten envelope.
Supply side guide roller rotated in counterclockwise direction (raises guide roller) to make the tape float above the helical lead. The supply side guide roller is then rotated in the clockwise direction to flatten the envelope.
Take-up side guide roller rotated in counterclockwise direction (raises guide roller) to make the tape float above the helical lead. The take-up side guide roller is then rotated in the clockwise direction to flatten the envelope.
Figure 4-35.
driver by the method shown in Figure 4-33, and adjust the A/C head so as to get the maximum envelope waveform. (Note: At this time adjust so as to get the maximum envelope waveform nearest the A/C head position which has been set in case of X value rough adjustment as stated in Page 20, 3- 2.) 4 Tighten finally the screws 1 and 2. Be sure to tighten at first the screw 1 and then the screw 2. Final tightening torque is 0.6N·m (If the screw 2 is tightened first, the X value may deviate.) 5 Adjust the playback switching point (Refer to the electric adjustment method.) 6 Playback the self-picture-recorded tape, and check the flatness of envelope waveform and sound.
Notes: When the A/C head X value adjustment is performed, be sure to perform at first X value rough adjustment (refer to Page 20, 3-2).
1 2
Figure 4-36.
21
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
REPLACEMENT OF THE CAPSTAN D.D. (DIRECT DRIVE) MOTOR
· Remove the mechanism from the main PWB (refer to Page 5 item 1. When removing the mechanism from the main PWB"). · Removal (Follow the order of indicated numbers.) 1. Remove the reel belt 1. 2. Remove the three screws 2.
2
REPLACEMENT OF DRUM D.D. MOTOR
1. Set the ejection mode. 2. Withdraw the main power plug from the socket. · 1. 2. 3. 4. 5. Removal (Perform in numerical order.) Disconnect the FFC cable 1. Unscrew the D.D. stator assembly fixing screws 2. Take out the D.D. stator assembly 3. Unscrew the D.D. rotor assembly fixing screws 4. Take out the D.D. rotor assembly 5.
Capstan D.D. motor
Capstan D.D. motor control PWB
Notes: 1. In removing the D.D. stator assembly, part of the drum earth spring pops out of the pre-load collar. Be careful not to lose it. 2. Install, so that the D.D. rotor ass'y and upper drum ass'y mounting direction check holes align. (Align the upper drum dent with the rotor hole.) 3. Be careful not to damage the upper drum or the video head. 4. Protect the hole elements from shock due to contact with D.D. stator or D.D. rotor ass'y. 5. After installation adjust the playback switching point for adjustment of servo circuit.
2 D.D. stator ass'y 3 1 4 FFC
1
Reel belt
Figure 4-37.
· Reassembly 1. Taking care so that the capstan shaft does not contact the mechanism chassis, set its position on the mechanism chassis, and then install with the three screws. 2. Install the reel belt. Notes: 1. After installing the capstan D.D. motor, be sure to rotate the capstan D.D. motor and check the movement. 2. Set the tape, and check for the tape crease near the reverse guide in the playback mode. Adjust the A/C head and azimuth as stated in Page 20 Replacement 2. If crease is found, adjust as stated in Page 19 "HEIGHT ADJUSTMENT OF REVERSE GUIDE".
4
5
D.D. rotor ass'y
Upper drum
Figure 4-38.
22
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
REPLACING THE UPPER AND LOWER DRUM ASSEMBLY
· Replacement (Perform in the numerical order) 1 Remove the motor as stated in Page 22 D.D. motor replacement. 2 Remove the drum earth brush ass'y 2. 3 Remove the drum base 3 from the upper and lower drum assembly 1.
ASSEMBLING OF PHASE MATCHING MECHANISM COMPONENTS
· Assemble the phase matching mechanism components in the following order. 1. Assemble the pinch roller assembly and pinch drive cam. 2. Mounting the shifter (on the back of the mechanism chassis). 3. Mounting the master cam (on the back of the mechanism chassis). 4. Assemble the connection gear, slow brake and loading motor parts.
[Cares when replacing the drum] 1. Be careful so that the drum earth brush is not lost. 2. Do not touch directly the drum surface. 3. Fit gently the screwdriver to the screws. 4. Since the drum assembly is an extremely precise assembly, it must be handled with utmost care. 5. Make sure that the drum surface is free from dust, dirt and foreign substances. 6. After replacing the drum be sure to perform the tape running adjustment. After that, perform also the electrical adjustment. · Playback switching point adjustment · X-position adjustment and check · Standard and x-3 slow tracking adjustment 7. After replacing the drum clean the drum.
· Pinch drive cam and pinch roller assembling method.
(Place the following parts in position in numerical order.) (1)Reverse drive lever 1 (2)Reverse guide spring 2 (3)Reverse guide lever ass'y 3 (4)Reverse guide height adjusting nut 4 (5)Pinch drive cam 5 (6)Pinch roller ass'y 6 (7)Open lever 7
7
2 1
4 3 2 1
6
5
3
Figure 4-40.
Figure 4-39.
23
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X 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 to the stopper.
Fit the pinch drive cam so that the notch of pinch drive cam aligns with the dent of pinch drive lever assembly.
Fit the pinch drive cam so that the notch of pinch drive lever assembly aligns with the half-round notch of chassis. Pinch drive lever ass'y
Figure 4-41-1.
2Insert Pinch Roller/Pinch Double Action Lever Ass'y.
3Insert Open Lever.
Pinch Roller Double Action Lever Ass'y Phase Matching Point 2
Open lever
Figure 4-41-2. 24
Figure 4-41-3.
INSTALLING THE SHIFTER
1. 2.
Drum
3. 4.
Capstan D.D. motor
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X Make sure that the loading gear is at the PHASEMATCHING point 1 as shown below. Install, paying attention to insert point 5 and release point 3. For the phase matching at the insert point 1, see the PHASE-MATCHING point 2 as shown below. Finally fix the inserts 1 and 4.
Reel pulley
(Bottom side of mechanism chassis)
Figure 4-42.
Phase-Matching point 2 Loading gear (T) Round mark Insert point 1 Shaft 1 Half round notch
Sifter
Insert point 3
Insert point 2
Insert point 4
Shaft 1
Rotation point 2 Shaft 2
Insert point 5
Shaft 1 Phase-matching point 1
Release point 3
Figure 4-43.
25
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
INSTALLING THE MASTER CAM (AT 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.
REPLACEMENT OF LOADING MOTOR
· Removal
E ring (XRESJ30-06000) Master cam Apply grease Apply grease
Fully turn clockwise
Fully turn counterclockwise Face the wide tooth side ward No grease
Figure 4-44-1.
Note: See the figure below for the phase matching between the master cam and the casecon drive gear. 3. Finally fix with the E ring.
Master cam
Figure 4-45.
Casecon drive gear
Half-round notch Round mark
· Replacement Remove the loading motor, and install the replacement loading motor as shown below.
10.2 +0.2 mm 0.2
When installing the master cam, align the casecon drive gear round mark with the half-round notch of master cam.
Figure 4-44-2.
Figure 4-46. The loading motor pressing-in must be less than 147 N (15 kgf). Adjust the distance between motor and pulley to 10.2 +0.2 0.2 mm). 26
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
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.
Drive angle
Drive gear R
Frame
Figure 4-48.
27
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
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 can not be completed. · Instruments required: Colour TV monitor Dual-trace oscilloscope Alignment tape (VROCPSV), (VROATSV) Blank video cassette tape DC voltmeter Screwdriver for adjustment
Servicing precautions When the IC710 (E2PROM) has been replaced, make the following reprogramming. Depending on models, the IC710 (E2PROM) has been factory-adjusted for it's memory function. It's therefore necessary to reprogram the memory function for the model in question. Note that the servo circuit requires readjustments for the head switching point, slow and still modes. · Location of controls and test points
TP101 P201
R1626 T1601
IF
TP802 TP801
MAIN
Figure 5-1.
28
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
SERVO CIRCUIT ADJUSTMENT
ADJUSTMENT OF HEAD SWITCHING POINT
Measuring instrument Mode Cassette Test point Dual-trace oscilloscope Colour TV monitor Playback Alignment tape (VROCPSV) Pin(2) of P201 (H.SW.P.) to CH-1, VIDEO OUT jack to CH-2 (CH-1 trigger slope switch at (+), Internal trigger at CH-1 side.) 6.5 ± 0.5H (lines)
CH-2 VIDEO OUT CH-1: 1V/div 50µs/div CH-2: 2V/div 50µs/div
CH-1 HEAD SWITCHING PULSE
6.5 ± 0.5H (lines)
V-sync.
Figure 5-2.
Specification
ADJUSTMENT OF PAL SYSTEM SP/LP SLOW TRACKING PRESET
Measuring instrument Mode Cassette Control Specification Colour TV monitor Playback Self-recorded tape (SP/LP mode)(See Note below) Tracking control buttons (]) or ([) Minimized noise on monitor screen
1. Remove the front panel and play the alignment tape. (VROCPSV) 2. Press the PLAY button. (Playback picture on the monitor screen.) 3. Make for a moment short-circuit P802, located at the front side on the main PWB. Press the PLAY button again. Be sure that all the fluorescent display tubes light up into the TEST mode.(See Note below) Be sure the " > " appears in the fluorescent display tubes flashing (about 1Hz) into the auto PG adjustment operating. Note: When the manual PG adjustment, observe the waveform with an oscilloscope and make adjustment FF or REW button so that the specification. 4. Stop the " > " appears in the flashing of fluorescent display tubes at adjusted. 5. Press the STOP button in the return to manual mode. 6. Make this checking of waveform on the oscilloscope screen be as shown in Figure 5-2. just after the head switching point have been adjusted. Note: 1 Set-up of TEST mode. When the adjustment of HEAD SWITCHING POINT, AUTO TRACKING function is invalid. 2 When the cassette housing control ass'y is removed, set-up of mechanism operating mode. 1) Replug the AC power cord it a few minutes later. 2) Make a short-circuit P801 located at the front side on the main PWB, and press both ([) and (]) tracking control button at the same time to set the tracking in center. 3) AC power cord is plugged in. 4) Then set-up of mechanism operating mode is completed, replug the AC power cord a few minutes later.
1. Have the unit to receive a good TV broadcast or feed a video signal to the VIDEO IN jack. (See note 2 below) 2. Set the tape speed in SP mode by using the remote control and record the signal on tape. 3. Rewind and play the tape where signal was recorded in above step. 4. Press the SLOW button on the remote control, and playback the recorded portion in the slow mode. 5. Make for a moment short-ciucuit P802, located at the front side on the main PWB. Be sure that all the fluorescent display tubes light up into the TEST mode. 6. Look at the monitor screen and adjust the (]) or ([) TRACKING buttons so that the there is noise disappears from the screen. 7. Press the STOP button to return to normal mode. 8. Play the tape a few seconds then press the SLOW button again and make sure there is on noise in the screen.(For the LP mode put adjustment at the same adjustmet way as SP mode.) Notes: 1 Self-recorded tape means a cassette whose program was recorded by the unit being adjusted. 2 The TV program will not be recoded if RCA or 21pin plugs are pluged in the AUDIO/VIDEO input terminals. 3 The tracking control is enabled with the (])/([) button.
29
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
ADJUSTMENT OF PAL SYSTEM FV (False Vertical Sync) OF STILL PICTURE
Measuring instrument Mode Cassette Control Specification Colour TV monitor Playback still Self-recorded tape (SP mode) (See Note below 1) Tracking control buttons (]) or ([) No vertical jitter of picture
1. Play a cassette which was recorded by the unit in SP mode. 2. Press the PAUSE/STILL button to freeze the picture. 3. Look at the monitor screen and adjust (]) or ([) TRACKING buttons so that the vertical jitter of the picture to be minimized. 4. Play and freeze the self-recorded tape in SP mode and make sure vertical jitter of the picture is not noticeable.(For the LP mode put adjustment at the same adjustment way as SP mode.) Note: 1 Self-recorded tape is a cassette whose program was recorded by the unit being adjusted. 2 The tracking control is enabled with the (])/([) button.
6. Look at the monitor screen and adjust the (]) or ([) TRACKING buttons so that the there is noise disappears from the screen. 7. Press the STOP button to return to normal mode. 8. Play the tape a few seconds then press the SLOW button again and make sure there is on noise in the screen.(For the E P mode put adjustment at the same adjustmet way as SP mode.) Notes: 1 Self-recorded tape means a cassette whose program was recorded by the unit being adjusted. 2 The TV program will not be recoded if RCA or 21pin plugs are pluged in the AUDIO/VIDEO input terminals. 3 The tracking control is enabled with the (])/([) button.
ADJUSTMENT OF NTSC SYSTEM FV (False Vertical Sync) OF STILL PICTURE
Measuring instrument Mode Cassette Colour TV monitor Playback still Self-recorded tape (SP mode) (See Note below 1) Tracking control buttons (]) or ([) No vertical jitter of picture
Control Specification
ADJUSTMENT OF NTSC SYSTEM SP/EP SLOW TRACKING PRESET
Measuring instrument Mode Cassette Control Specification Colour TV monitor Playback Self-recorded tape (SP/EP mode)(See Note below) Tracking control buttons (]) or ([) Minimized noise on monitor screen
1. Have the unit to receive a good TV broadcast or feed a video signal to the VIDEO IN jack. (See note 2 below) 2. Set the tape speed in SP mode by using the remote control and record the signal on tape. 3. Rewind and play the tape where signal was recorded in above step. 4. Press the SLOW button on the remote control, and playback the recorded portion in the slow mode. 5. Make for a moment short-ciucuit P802, located at the front side on the main PWB. Be sure that all the fluorescent display tubes light up into the TEST mode. 30
1. Play a cassette which was recorded by the unit in SP mode. 2. Press the PAUSE/STILL button to freeze the picture. 3. Look at the monitor screen and adjust (]) or ([) TRACKING buttons so that the vertical jitter of the picture to be minimized. 4. Play and freeze the self-recorded tape in SP mode and make sure vertical jitter of the picture is not noticeable.(For the EP mode put adjustment at the same adjustment way as SP mode.) Note: 1 Self-recorded tape is a cassette whose program was recorded by the unit being adjusted. 2 The tracking control is enabled with the (])/([) button.
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
ADJUSTMENT OF VCO CIRCUIT
Measuring instrument Mode Test point Control Specification Colour TV monitor DC voltmeter RF signal at E12-CH (by VHF signal generator) Pin(1)(AF1) of TP101. Pin(4)(GND.) of TP101. T1601 VCO control 2.5±0.5V
1. Set VCR to Power On mode. 2. Press "Test key" mode. 3. Press channel E12 of R/C at 87.5% mod. and 70dBµ of antenna terminal (Caution: Do not press SW button on set. Use R/C.) 4. Connect a DC voltmeter to test point shown in table. 5. Look at the voltmeter and adjust T1601 at voltage specified.
ADJUSTMENT OF RF AGC
Measuring instrument Mode Test point Colour TV monitor Oscilloscope RF signal at E12-CH (by VHF signal generator) Pin(3) Signal of TP101. Pin(4) GND of TP101. R1626 RF AGC control ----------------------------
Control Specification
1.Receive E12 channel signal at 87.5% mod. and 70dBµ of antenna signal. 2.Connect an oscilloscope to test point shown in table. 3.Look at the oscilloscope and adjust R1626 counterclockwise until sync-tip becomes from noisy to clear just before shrink position. 4. Press "Test key " mode and auto tune to receive signal.
31
6. MECHANISM OPERATION FLOWCHART AND TROUBLESHOOTING GUIDE
CASSETTE INSERTION STOP
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
MECHANISM OPERATION FLOWCHART
End
G mechanical timing
Insert cassette.
Cam graph E
Mode check Cam mark
25
Cassette is ejected and loading motor stops.
Mode detection outside (D709 SW B)
20
Double action rack slides. Start sensor close. Loading motor starts in normal direction and master cam counter clockwise.
Mode detection inside (D708 SW A)
15
10
5
Cassette inserting
120
PU1 179 PU2 200 VSR 233 FF 316 PB 265 SLOW 282 STOP 334
Loading motor turns in reverse direction and master cam counterclockwise.
NO
0 180 240 300 380
60
CA/END CS/EJ
Does mechanism position sw. come off within 2.5 sec.?
YES
0
19.812
UL 81
(Cassette is judged caught halfway.)
32
PU PU2 VSR PB SLW FF STP
10.354 12.812
EJ
UL
Mode detection outside 1 1 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 1 1 0 1 0 0 1 1 0 1 1 0
0 0
0
0
0
1 1 1
Are start/end sensors at low level NO before cassette insertion ? (Cassette LED or some other part is judged defective.)
YES
Mode detection inside
1 1
0
0
0
0 1 1
S sensor
1 1
0
1
1 or 0
Drum motor starts.
Mode detection inside sensor B 0 1 1 1 1 0 1 1 0
Open S sensor Close
Mode detection inside
sensor A 1 1 1 0 0 0 0 0 0
CS/EJ
Tape loading.
ULD
PU1
PU2
VSR
Pinch roller comes into contact.
PB
SLOW
FF
STOP
Fullloading
Cam switch is at PB position.
Loading motor stop.
Is drum FG pulse outputted ?
YES
NO
Unloading
End
STOP PLAY PLAY VSR PLAY VSR STILL
REC/PLAY
Press REC/PLAY key.
Press STILL key.
Press REW key.
Press PLAY Key.
Capstan motor turns counterclockwise. Pinch roller releasing Release pinch roller. Cam switch is at PU2 position. Stop loading motor.
Loading motor turns in counterclockwise direction and master cam clockwise.
Loading motor turns clockwise and master cam counterclockwise.
Loading motor turns counterclockwise and master cam clockwise.
Picture appears. Slow brake comes into contact with capstan motor.
Slow brake pressing
Capstan motor turns counterclockwise. PB speed.
Is take-up reel sensor signal outputted ? Cam switch is at STILL position. Idler swinging Turn capstan motor in reverse direction. Loading motor turns clockwise. Capstan motor stops. Release the supply auxiliary brake. Cam switch is at PU1 position. Pinch roller pressing Turn loading motor counterclockwise. Press pinch roller. Press STOP key. Cam switch is at VSR position. Capstan motor turns in reverse direction. Stop loading motor. Set capstan motor to search speed. Is take-up reel sensor signal outputted ?
YES
NO
YES
Cam switch is at PB position.
End Loading motor stops.
End
Unloading
End
33
REC/PLAY STOP Stop capstan motor. End
PLAY
VSF
Press FF key.
Set capstan motor to search speed.
End
End
NO
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
Unloading
STOP STOP CASSETTE EJECT
FF/REW
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
Press FF/REW key. Press EJECT key.
FF/REW operation
Turn capstan motor in normal or reverse direction, after the remaining tape has been detected. Loading motor turns in clockwise and master cam counterclockwise. Tape unloading Capstan motor turns in reverse direction. End Cam switch is at UL position.
Stop loading motor. FF/REW 4 supply reel pulses outputted ? Press STOP key.
YES NO NO
STOP Capstan motor turns clockwise.
34
YES
Loading motor turns counterclockwise.
Does the take-up reel pulse output two edges?
Capstan motor turns counterclockwise in about 2 seconds.
Brake function Stop capstan motor.
Capstan motor turns clockwise.
Cam switcn is at Stop position. Loading motor turns clockwise. Loading motor stops. Cam switch is at Eject position. Cassette eject Loading motor stops.
End
Capstan motor stops.
End
MECHANISM TROUBLESHOOTING 2. REC/PLAY FAILURE (MODE RELEASE)
1. FF/REW FAILURE (NO TAPE WINDING)
Press FF key.
Is master cam at FF position ? Does loading motor operate ?
YES YES YES NO
NO
Does loading motor operate?
NO
Is voltage applied NO to loading motor ? Voltage supply system in trouble. Is the master cam NO at PB position ?
NO
Is voltage applied NO to loading motor ?
YES
Voltage supply system in trouble.
YES
YES
Modes changing smoothly through cam switch ? Loading motor is damaged. Replace it.
YES
Modes changing smoothly through cam switch ?
Loading motor is damaged. Replace it.
YES
Loading motor control system in trouble.
Mode sensor system in trouble or master cam malpositioned.
Loading motor control system in trouble.
Does capstan NO motor turn in FF (or REW) direction ?
NO
Are Vco 12V and Vcc 5V applied ? Does capstan motor turn ?
YES
Voltage supply system in trouble.
NO
Are Vco 12V and Vcc 5V applied ?
YES
NO
Voltage supply system in trouble.
35
YES YES
YES
YES
Replace the capstan motor.
Replace the capstan motor.
Are idler wheel NO ass'y and reel disk in mesh ?
Replace the idler ass'y.
Are idler wheel NO ass'y and reel disk in mesh ?
Replace the idler ass'y.
YES
Is the pulse NO outputted from reel sensor ?
Replace the reel sensor.
Is the pulse NO outputted from reel sensor ?
Replace the reel sensor.
YES
The cassette tape is presumably damaged.
Check main PWB.
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
3. WINDING FAILURE AT VSR
4. UNUSUAL SOUND IN EACH MODE
4-i) Unusual sound in cassette insertion and ejection mode Go to 2. REC/ PLAY FAILURE routine.
YES
Is Playback function normal ? Replace cassette control ass'y.
NO
YES
Press REW key. Go to 2. REC/ PLAY FAILURE routine.
NO
Is unusal sound heard during cassette coutrol running ?
Master cam shifting to VSR position ? Unusual sound heard with pinch roller lever going up or down ? Replace idler gear ass'y. Is unusual sound heard during loading/unloading ?
YES NO YES
NO
YES
Check pinch roller drive cam, pinch roller drive lever and reverse guide for their actions. Replace damaged one with new one.
Are idler wheel NO ass'y and supply reel disk in mesh ?
YES
36
Replace limiter pulley ass'y. Replace loading motor block. Replace reel sensor.
Is supply reel disk NO winding torque normal ?
YES
Is pulse outputted NO from reel sensor?
YES
Check main PWB.
4-ii) Unusual sound in FF/REW mode
Is reel disk height as specified ?
NO
Adjust reel disk height.
YES
Thrust gap found at reel disk ?
NO
Check reel disk and main chassis. And replace defective parts.
YES
Drive system out of contact with any part on main PWB ? Rearrange the parts on main PWB.
YES
NO
Turn capstan motor by hand. Unusual sound heard ? Replace capstan motor.
YES
37
NO
Check drive system's gears for damage. Replace damaged gear with new one. · Reel disk · Limiter pulley ass'y · Idler wheel ass'y
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
7. TROUBLESHOOTING
FLOW CHART NO.4 POWER TROUBLESHOOTING(4)
No power is turned on No power
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
FLOW CHART NO.1 POWER TROUBLESHOOTING(1)
Unplug the AC power cord. Replug it a few minutes later.
YES
NO
See FLOW CHART NO.2 POWER TROUBLESHOOTING(2)
Does power control (H) signal at pin (4) of IC701 change from "L" to "H" level?
NO NO
Check IC701.
YES
Is the fuse good?
YES
NO
Replace fuse.
Does the base of Q951 change from about 5.0V to 4.5V?
Check IC701 and all the way up thru to Q951.
YES
Is AT 5V voltage line normal?
YES
NO
Check primary circuit.
Is voltage of 5V sent out the collector of Q951.
NO
Check peripheral circuit of Q951 and PC 5V line.
YES Are AT 42V, AT 23V, AT 12.6V, AT -25V NO and filament voltage lines normal?
Check each rectifier circuits and short-circuit of secondary circuit.
Check peripheral circuit for poor soldering.
YES
Is "H" level applied at pin(1) of IC701?
NO
Check peripheral circuits of Q706 and P-FAIL (L) signal line etc.
38
YES
YES
Check system control circuit(IC701).
FLOW CHART NO.5 POWER TROUBLESHOOTING(5)
No power is turned on from STANDBY mode.
FLOW CHART NO.2 POWER TROUBLESHOOTING(2)
Is AT 5V voltage line normal?
NO
In case of Fuse(F901) blown out.
Check rectifier circuit of AT 5V and short-circuit of secondary circuit.
Replace F901, Q901, IC902 and R904, check D901, D902, D903 and D904 as a result of check, if poor, replace at the same time.
Check short-circuit or leak of D921, D922, D923, D903, D924, D925, D926 and secondary circuit.
Does STBY CTL signal at pin(94) of IC701 change from "L" to "H" level?
YES
NO
Check the operation of IC701.
Does the filament STBY SW. circuit Q947 is turn on?
YES
NO
Check peripheral circuit of Q947, Q948, Q949, D940.
FLOW CHART NO.3 POWER TROUBLESHOOTING(3)
In case of abnormal noise(sound)
Does the STBY -25V SW. circuit Q944 is NO turn on?
YES
Check peripheral circuit of Q944.
Check D921, D922, D923, D924, D925 and D926.
NO
The Check D921, D922, D923, D924, D925 and D926 as a result of check, if poor replace.
Does the STBY 5V SW. circuit Q945 NO is turn on?
Check peripheral circuit of Q945, Q946, Q950.
FLOW CHART NO.6 POWER TROUBLESHOOTING(6)
Key-in input is not received
FLOW CHART NO.8 KEY CONTROL TROUBLESHOOTING(1)
In case of output voltage at low level.
Check peripheral circuits IC902, IC921, C933, R932, R929, R930 and R931.
NO
NO
The IC901, C913, R908, R909, R910 and R911 as a result of check, if poor replace.
YES
Does the key switch make good contact, when the cassette tape is inserted? YES
NO
Check switch contact.
Check IC902 and peripheral circuits pin(9) of IC901. Replace IC901.
NO YES
YES NO
Is there the function control voltage inputted at pins (96),(97) and (98) of IC701, when the jog shuttle ring are activated? Replace IC701. ANGLE TERMINAL SW1(Pin96) SW3(Pin97) SW4(Pin98) SW2(GND)
-52 -38
Check peripheral circuit of pins(96), (97) and (98) of IC701, and the jog shuttle ring.
Check short-circuit or leak of T901.
Replace T901.
YES
-60 -50 -40 -30 -20 -10
-15
0
10
15
20
30
40
38
50
52
Check primary circuit and peripheral circuit of Q901.
60
FLOW CHART NO.7 TIMER TROUBLESHOOTING
SW 1/SW 2 INPUT VOLTAGE(V)
39
NO
The flourescent display tube fails light up.
FLOW CHART NO.9 KEY CONTROL TROUBLESHOOTING(2)
Key-in input is not received
Check STBY 5V line.
Is the supply voltage of 5V fed to pin(8) of IC801?
YES NO
Is the supply negative voltage of -25V fed to pin(1) of IC801?
Check negative voltage line(STBY -25V) and power circuit.
Does the key switch make good contact, when the cassette tape is inserted?
NO
Check switch contact.
YES
YES Is there the function control voltage NO inputted at the pins(87) and (88) of IC701, when the keys are activated? YES
Check peripheral circuit of pins(87) and (88) of IC701, and the function keys.
5.0V
NO
Check power circuit and peripheral circuit of D952.
Replace IC701.
4.4V 3.8V 3.1V 2.5V 1.9V 1.2V 0.6V
Is the filament voltage applied between (1)/(2) and (31)/(32) of the fluorescent display tube? Also negative voltage applied between these pins and GND.
KEY OFF CASSETTE P801 CASSETTE P801 TEST P802 TEST P802 S809 MENU S810 CH(+) S811 EJECT S813 POWER KEY 0 IN
S887 REW S886 FF S885 STOP S884 PLAY S883 PAUSE/STILL S882 REC S807 CH(-) S810 MENU KEY 1 IN
YES NO
Does the fluorescent display tube function?
Check for cracks on the fluorescent display tube.
YES
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
Replace IC801.
FLOW CHART NO.10 INFRARED R/C TROUBLESHOOTING
A cassette tape is taken in, but ejected at once.
FLOW CHART NO.12 CASSETTE CONTROL TROUBLESHOOTING(2)
VC-A230NZ/X VC-A280NZ/X VC-A480NZ/X
No operation is possible from the infrared remote control.
NO
Does the infrared remote control function?
Replace infrared remote control as required.
YES NO
Does the start sensor pulse at pin (79) of IC701 change from "L" to "H" level when the cassette tape is loaded?
NO YES NO
Check line between start sensor and pin (79) of IC701.
Is the supply voltage of 5V fed to C804 of (+) side? Check AT 5V and GND lines.
YES NO
Does the end sensor pulse at pin (85) of IC701 change from "L" to "H" level when the cassette tape is loaded?
Replace receiver.
YES
Check line between end sensor and pin (85) of IC701.
Is "L" pulse sent out from pin(1) of the receiver when the infrared remote control is activated?
YES NO
Does the master cam mode shifter operate normally when the cassette tape is loaded?
NO
Check line between cam switch and IC701.
Check between at pin(1) of re