Sharp VC-90ET User manual

VC-90ET
SHARP
SERVICE
MANUAL
VIDEO
CASSETTE
RECORDER
move.
VC-90ET
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 should be used.
CONTENTS
SPECIFICATIONS.
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DISASSEMBLY
AND
REASSEMBLY...........ccssesscsscsecsscrececeeneesneeseeserseeseserscsvenseeseneeesenenaes
FUNCTION
OF
MAJOR
MECHANICAL
ADJUSTMENT, REPLACEMENT AND ASSEMBLY
OF
MECHANICAL
UNITS
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ses
ADJUSTMENT
OF
ELECTRICAL
CIRCUITRY
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TROUBLESHOOTING
GUIDE
BLOCK
DIAGRAM
WAVE
FORMS
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SCHEMATIC
DIAGRAMS
WIRING
SIDE
PWBS
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REPLACEMENT
ELECTRICAL
PARTS
LIST
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EXPLODED
VIEWS.
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PACKING
OF
THE
SET
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SS SS
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eS
SHARP CORPORATION

VC-90ET
Format:
Video recording system:
Video signal:
Recording playing time:
Tape width:
Tape speed:
Antenna:
Receiving channel:
RF converter output signal:
Power requirement:
Power consumption:
Operating temperture:
Storage temperature:
Weight:
Dimensions:
VIDEO
Input:
Output:
AUDIO
Input:
Output:
Accessories included:
Note:
SPECIFICATIONS
VHS
PAL,
SECAM
MESECAM,
NTSC
standard
Rotary,
slant
azimuth
two
head
helical
scan
system
PAL, SECAM, NTSC
colour or monochrome
(CCIR System B/G, I, D/K, M) signal
240
min
max.
with
SHARP
E-240
tape
(PAUMESECAM/SECAM
in
SP
mode)
8
hours
max.
with
SHARP
E-240
tape
(PAL/MESECAM/SECAM
in
LP
mode)
160
min
max.
with
SHARP
T-160
tape
(NTSC
in
SP
mode)
8
hours
max.
with
SHARP
T-
160
tape
(NTSC
in
EP
mode)
12.7mm
23.39
mm/sec.
(PAL
in
SP
mode)
33.35mm/msec.
(NTSC
in
SP
mode)
11.7
mm/sec.
(PALin
LP
mode)
16.68mm/msec.
(NTSC
in
LP
mode)
(PB
only)
11.12
mm/sec.
(NTSC
in
EP
mode)
75 ohm unbalanced
VHF E2~E 12, (44.25MHz~295.25MHz)
UHF E21~E69, (471.25MHz~885.25MHz)
UHF
Channel
E30~E39
(adjustable).
Preset
to
Channel
E36
AC110~240V,
AUTO
50/60
Hz
Approx. 24W (at AC220V 50Hz)
5°C to 40°C
- 20°C to 55°C
5.5kg
430
mm
(W)
x
348
mm
(D)
x
89
mm
(H)
0.5~2.0 Vp-p, 75 ohm
1.0 Vp-p, 75 ohm
Line:
-
8
dB,
more
than
47k
ohm
(with
-
4dB/-
8dB
ATT.
SW
)
Line:
-
8
dB,
less
than
1k
ohm
Antenna
75
ohm
coaxial
connector
cable
(plug
provided)
Operation
Manual
SHUTTLE remote contro!
Dry Battery
AV Cable
As
part
of
our
policy
of
continuous
improvement,
we
reserve
the
right
to
alter
design
and
specifications
without
notice.
The
antenna
must
correspond
to
the
new
standard
DIN
45325
(IEC
169-2)
for
combined
UHF/VHF
antenna
with
75
ohm
connector.

w
wn
VC-S0ET
DISASSEMBLY AND REASSEMBLY
Remove the four upper cabinet fastening screws
Remove the eight bottom panel fastening
screws @.
Remove the one front panel fastening screw ©.
Release the three clips @ and remove the front
panel.
Remove the HiFi PWB holder ©.
Remove the one SYSCON SERVO PWB Holder
fastening screw ©.
Remove the one SUB CHROMA PWE Holder
fastening screw @.
8.
10.
11.
12.
13.
Remove the one RF Converter Holder fastening
screw @).
. Remove the two antenna terminal cover
fastening screws @.
Remove the two main PWB fastening screws @.
Remove the two head amp PWB fastening
screws (1) .
Remove the two power unit fastening screws (2,
Remove the four mechanism chassis fastening
screws (13).
. Release the timer PWB (9 fastening clips.
. Release the operation PWB (5 fastening clips.

Full erase head ass'y Kis
Supply pole base ass'y(2)
" V¥C-90ET
FUNCTION OF MAJOR MECHANICAL PARTS (TOP VIEW)
Take-up pole base ass’y 21)
Drum ass'y
Tension arm assy (3)
Brake shifter (4)
Back tension lever (5)
Supply reel disk (6)
Main supply brake lever &
Full erase head ass’y ;
Erase the whole records on the tape in the
recording mode.
Tension arm ass'y
Detects the tension of tape while running, and
brakes
the supply reel disk via the tension bane.
Brake shifter
Set the position of brake or the like in accordance
with the modes such as stop and playback.
Back tension lever.
Back tension lever
Bakes the supply reel disk to a certain degree to
prevent tape slackening during “loading” and
“shifting from playback to video search rewind”.
Main supply brake
Brakes the supply reel disk to prevent tape
slackening when the unit is stopped in fast forward
or rewind mode.
Main take-up brake
Brakes the take-up reel disk to prevent tape
slackening when the unit is stopped in fast forward
or rewind mode.
Half-loading level
Bring the tape in contact with the A/C head,
putting it in half-loading state in the fast forward
orrewind mode.
Video search brake lever
It is in contact with the take-up reel disk normally,
and brakes it to a certain degree. It applies larger
brake in the video search rewind mode.
24) V.H Cleaner arm ass’y
20) A/C head ass'y (19) Cam switch
(25) Solenoid ass’y (23) Dew sensor
fo] 2
(18) Loading motor
Nate,
A|_—(16)
Pinch
roller
lever
ass'y
°
ie
(5)
Relay
shifter
lever
9
eYay a
=
;
(14)
Capstan
D.D.motor
©) 3 (13) Reverse guide
(12) Take-up reel disk
Sal
(GO)
(11)
Video
search
brake
lever
S
fi
(10) Half-loading lever
(9) Main take-up brake lever
(8) Idler gear ass‘y
Reverse guide
Pulls out the tape in the video search rewind mode,
and controls the tape drive train height with the
upper and lower guides.
Relay shifter lever
Transmits the operation of the master cam to the
brake shifter, and operates the reverse guide.
Pinch roller lever ass’y
Press-fits the tape to the capstan during tape
running. The right protrusion switches the clutch
of the cassette housing control assembly in “ tape
eject”, and makes the mechanism eject the tape.
Master cam
Turns clockwise during loading, and
counterclockwise during unloading, and moves the
shifter or the like in accordance with each mode.
Loading motor
A motive power which drives the mechanism. It
transmits the power to the master cam and
cassette housing control assembly via the belt.
Cam switch
Rotates synchronously with the master cam, and
detects the position of each mode by means of the
internal switch.
Dew sensor
Detects the generation of dew in the set. It stops
the mechanical action of the set when finding any
dew in the set.

VC-SOET
FUNCTION
OF
MAJOR
MECHANICAL
PARTS
(BOTTOM
VIEW)
Relay gear drive lever
Reel sensor
(9) Take-up loading gear
(10) Supply loading gear
(8) Auxiliary fast forward
brake lever
Brake solenoid (5) (6) Reel pulley
Slow brake
Gets in contact with the capstan D.D. motor linking
to the master cam in the slow still mode, and
brakes it to a certain degree.
Capstan D.D. motor
A motive power which runs the tape. It transmits
the power via the reel belt.
Reel belt
Transmits the power to run the tape to the reel
Brake solenoid
Adsorbs and holds the brake shifter in the fast
forward and rewind modes, and releases it in the
Reel pulley
Transmits the power of the capstan D.D. motor to
the reel disk via the reel idler.
Reel sensor
An element which sheds the light onto the
reflection plate affixed to the bottom side of the
reel disk, and detects the rotation of the reel disk
through receiving the reflected light.
Auxiliary fast forward brake lever
Brakes the supply reel disk to a certain degree in
the fast forward and rewind modes.
Take-up loading gear
Shifts the take-up pole base and guide roller via
the loading relay gear, and applies the tape
around the durm assembly, as well as transmits the
power to the supply loading gear.
Supply loading gear
Shifts the supply pole base and guide roller via the
take-up loading gear, and applies the tape around
the drum assembly.
Relay gear drive lever
Transmits the movement of the master cam to the
take-up loading gear via the loading relay gear.

VC-90ET
ADJUSTMENT, REPLACEMENT AND ASSEMBLY
OF MECHANICAL UNITS
Here we will describe a relatively simple service
work in the field, not referring to the more
complicated repairs which would require the use of
We are sure that the easy-to-handle tools listed
below would be more than handy for periodical
maintenance to keep the machine in its original
special
equipment
and
tools
(drum
assembly
working
condition.
replacement, for example).
TOOLS
NECESSARY
FOR
ADJUSTING
THE
MECHANICAL
UNITS
The
following
tools
are
required
for
proper
service
and
satisfactory
repair.
Jig Item
Reel Disk Height Adjustment Jig
JiGRHO002
JiGMP0001
JiGACH-F18
JiGTGOO90
JiGTG1200
JiGTHOO06
JiGVHT-063
JiGSG2000
JiGHWO0009
JiGHWO0015
ac
VROATFPS CA
Master Plane
AIC Head Tilt Adjustment Jig
Torque Gauge (90g)
Torque Gauge (1.2 kg)
Gauge Head
Cassette Torque Meter
Tension Gauge (300g)
Tension Gauge (2.0kg) _
Hex Wrench (0.9mm)
Hex Wrench (1.2mm)
Hex Wrench (1.5mm)
B
B
fa
c
A
CZ
Alignment Tape (NTSC) a
c
Alignment Tape (PAL)
Hi-Fi Alignment Tape (PAL)
Alignment Tape (SECAM)
HiFi Alignment Tape (NTSC)
Code
Rep ht
Y
U
M
N
Ww
D
D
cB
Configuration
These jigs are used for checking and
adjusting the reel disk height
This Jig is used for setting the A/C
head tilt.
These jigs are used for checking and
adjusting the torque of take-up and
supply reel disks.
This cassette torque meter is used
for checking and adjusting the
torque of take-up for measuring
tape back tension.
There are two Gauges used for the
tension measurements, 300 g and
2.0 kg.
These Jigs are used for loosening or
tightening special hexagon type
screws.
These Tapes are especially used for
electrical fine adjustment.
f

VC-90ET
Jig Item Configuration
JiGDT-0001 a
Tension Gauge Adapter JiGADP003 a
Special Bladed Screwdriver jens |
B
Tension Band and Plate ;
Adjustment
Jig
JiGDRiVER-6
C
B
B
This is used for replacement of the
Drum
Replacing
Jig
VCR's
upper
drum.
This Jig is used with the tension
gauge. Rotary Transformer
Clearance Adjusting Jig.
This Screwdriver is used for
adjusting the guide roller height.
This Jig is used for adjusting the
tension band and tension plate.
This is used to screw down resin-
made parts: the specified torque is
5kg.
B
A
Torque Driver (5kq) JiGTD1200
JiGDRIVER1 10-7
15 | Box Driver
JiGDRIVER110-4 Al
Retaining Guide Height JiGGH-F18 ai
Adjustment Jig
jewore Jw |
NOTE:
Current JiGMA0001 contains Master Plane (JiGMP0001) and Disk Height Adjusting Jig
(JiGRHO001).
Even though new Disk Height Adjusting Jig GiGRH0002) covers greater height, this new Jig
(JiGRH0002) can be used for current JiGRH0001, but current Jig JiGRH0001) cannot be used as
JiGRH0002.
Master Plane (JiGMP0001) can be used with JiGRH0001 and JiGRH0002 as well.
This Jig is used for height
adjustment of the AVC head.
This Jig is used for height
adjustment of the retaining guide
and X-position.
This Jig is used for height
adjustment of the retaining guide.
G
K
p
8
V
U
U This Jig is used for height
Retaining Guide Height
adjustment of the reverse guide.
Adjustment Jig

VC-90ET
MECHANICAL PARTS REQUIRING PERIODICAL INSPECTION
Use
the
following
table
as
a
guide
to
maintain
the
mechanical
parts
in
good
operating
condition.
Maintained 500 | 1000
Guide roller ass‘y
Abnormal rotation or
significant vibration
requires replacement.
Clean with pure high
quality isopropyl
alcohol.
Supply impedance roller
ateral noises
Head occasionally
blocked
Supply impedance roller
(inner)
Supply impedance roller
flange
Retaining guide
Slant pole
Clean tape contact area
with the specified
cleaning liquid.
Video head
Poor color,
beating
Sound too small or
distorted
No tape running,
uneven color
No tape running,
tape slack
No tape running,
tape slack, no fast
forward/rewind
Full-erase head Clean tape contact area
with the specified
cleaning liquid.
A/C head
Capstan D.D. Motor
fem |
| za
Poor S/N ratio, no
El eee
Pinch roller ar ea
Clean rubber and
rubber contact area
with the specified
cleaning liquid.
Reel belt
Cassette not
loaded or
unloaded .
Loading belt/Cassette
loading belt
Tension band ass'y
Cassette not
loaded or
unloaded
Loading motor
Replace the roller o
the cleaner when it
wears down. Just
change the video head
cleaner arm assembly
AHC (Automatic Head
Cleaner)
for new one.
ial
below
ae
le
[04 |
Reel block*
*See the table below for servicing the reel block parts.
Supply/Take-up reel disks
i
No
tape
running,
ean
with
pure
hig
;
tape
Sack
°
auallty
isopt
opyl
Main
supply/take-up
brake
levers
Tape slack
Video search brake lever
Idler gear ass'y
No tape running
Reel
Pulley
Saas
NOTE: O: Partreplacement.
O: Cleaning (For cleaning, use a lint-free cloth dampened with pure isopropyl! alcohol).
A:
Oilrefilling
(The
indicated
point
should
be
lubricated
with
high
quality
spindle
oil
every
1000
hrs).
This
model
has
no
adjusting
parts
for
torques,
tensions,
etc.
If
the
reading
is
outside
the
specified
range,
cleanor
replace
the
part.

REMOVAL AND REASSEMBLY OF
CASSETTE HOUSING CONTROL ASSEMBLY
e
1.
2.
3.
Supply reel
disk
2.
Removal
Set the cassette ejected condition in the cassette
eject mode.
Unplug the recorder from the main source.
Follow the procedures below in the specified
order.
a) Remove the cassette loading belt ©.
b) Disconnect the FFC (Full Flat Cable) @.
©) Remove the cassette housing installation
screws @).
d) Slide and pull out the cassette housing control
assembly upward @.
Cassette housing installation
screw
ue (Full Flat Cable)
ou belt
When the belt is
detached, tuck it
as in the figure so
that it is kept free
from grease.
the tab in to the hole.
Cassette housing
(1) Cassette loading
When reassembling, insert
VC-SOET
5. Place the unit in the eject mode in removal or
reassembly of the cassette housing control
assembly.
6. Load the cassette once onto the cassette housing
control assembly after reassembly. (If the
cassette housing control assembly normally
operates after this, the phases of mechanism and
the cassette controller are accurately adjusted
after ejection.)
MECHANICAL OPERATION CHECK
WITHOUT CASSETTE
When power is on, the general operations of the
mechanism can be checked without a cassette.
Note the following points.
1. Check video search rewind and rewind, rotating
the take-up reel disk @ by hand (in either
normal or reverse direction). If it is not rotated,
the reel sensor works to shift the mechanism to
the eject mode.
2. When the stop button is pressed, the mechanism
does not stop at a normal stop position. It shifts
to the eject mode and stops.
3. When the stop button is pressed in the playback,
video search rewind, and video search forward
modes, the supply reel disk © keeps on rotating
for several seconds for elimination of tape slack
in the course of shifting to the eject mode. In
such a case, rotate the take-up reel disk ©
somewhat by hand, and the supply reel disk ©
stops, which can reduce the working time.
REPLACEMENT OF WORM WHEEL
ASSEMBLY
Figure 1-1. frame (L)
Reassembly
. Before installation of the cassette housing
control assembly, place the unit in the stop mode
with the power on, then unplug the power cord.
(The main body is placed in the eject mode.)
oe the procedures for removal in the reverse
order.
Notes:
1.
2.
3.
Be sure to unplug the power cord in removal and
reassembly.
Keep the cassette loading belt free from grease.
In case of its adhesion, clean the belt.
In using a magnet screw driver, be sure to keep it
away from the A/C head, FE (Full Erase) head, or
the drum.
-
In
removal
and
reassembly,
take
care
not
to
hit
the
cassette
housing
control
assembly
or
tools
against
the
guide
pin,
drum,
or
the
like
thereabout.
Start sensor
PWB
Cassette switch
connector
Worm bracket
B tight screw
Phase ‘Worm wheel ass'y
Cassette housing frame (R)
gear
Figure 1-2.

VC-90ET
® Removal
1. Unsolder the cassette switch connectors from the
start sensor PWB.
ui Start sensor PWB
Start sensor PWB
| fixing hook
Cassete switch [- Soldering
connector
Figure 1-3.
2. Lift the start sensor PWB pressing the two start
sensor PWB fixing hooks inward.
—_>
\ Lift hanes sensor PWB
Start sensor PWB fixing hook
Figure 1-4.
3. Unscrew one B tight screw to detach the worm
bracket.
Note:
The worm shaft bearing can easily come out of
position. So be careful not to lose it.
Worm shaft bearing
Worm bracket
worm wheel assy
Figure 1-5.
4. Remove the worm shaft assembly, pulley, and
cassette loading belt all from the cassette
housing frame (R).
Cassette
loading belt
ie Pulley
Cassette housing
frame (R)
%@
Phase gear Worm wheel ass'y
Figure 1-6.
10
Tally mark
5. Place the slider pin just above the worm wheel
assembly (Figure 1-7). (The retainer of the slider
is locked at two positions hen. So unlock it as in
the Figure 1-8.)
6. Pull out the worm wheel assembly toward you
pressing the switch lever upward. (Figure 1-7)
Slider pin
| is lever
Worm wheel ass‘y
2)
I" \—Phase gear
!
Qo Cut washer
Figure 1-7.
Retainer opening
{Also provided on the (L)} side
of cassette housing frame)
Cassette housing
frame {R)
Slider
Retainer
@
Press. Cassette housing frame
(R) {L) side
Figure 1-8.
Reassembly
. Turn the phase gear clockwise until the slider
comes to a halt in the cassette insertion
direction. (See the Figure 1-9.)
. Insert the set up worm wheel gear assembly into
the cassette housing frame (R), matching the
mark on the phase gear with the mark on the
worm wheel gear. Detach the cut washer on the
phase gear assembly and the phase gear for
easier installation of worm wheel assembly.
Note:
Make sure that the slider pin is in the groove of
the drive gear arm.

VC-90ET
5.
Tighten
oneB
tight
screw.
Note:
Do
not
overtighten
the
B
tight
screw
(no
more
than
5.0
+
0.5
kg.cm),
because
the
Slider pin i
phase
ses
SGX
pene
lower
threads
of
the
screw
hole
at
the
|
resin-mode
boss
can
be
broken.
6.
Place
the
start
sensor
PWB
on
the
cassette
housing
frame
(R).
shaft
FAI
6
C)
,
Note:
Check
that
the
switch
connectors
are
in
|
KS
:
the
cassette
switch
mounting
hole.
Taliymak™
|
\
7.
Finally
resolder
the
cassette
switch
connector
to
©
ZF
the
start
sensor
PWB.
X%
cut
washer
Tally
mark
\_
worm
wheel
Oy.
REASSEMBLY
OF
DRIVE
GEAR
(a)
7
(b)
Pillar
Worm
whee
square
hole
Figure
1-9.
:
I.
‘
Drive
gear
arm
.
.
Dnve gear spring (A)
3.
Install
the
pulley
and
the
cassette
loading
belt
on
the
worm
shaft
assembly.
Couple
the
clutch
to
the
clutch
lever.
And
mount
them
together
in
the
cassette
housing
frame
(R).
Note:
Keep
in
mind
that
the
clutch
switching
lever
should
be
in
the
correct
position.
The
mechanism
might
malfunction
if
the
lever
is
slightly
out
of
position.
(See
page
12.)
(a)
Reciprocating spring
Cassette
loading
belt
-
Drive
gear
arm
-
,
Cassette housing frame (R)
Clutch “\
Pulley z
Worm shaft ass’y
Orive gear
=p if
spring
(R)
Drive
gear
|
|
Cassette
:
:
“HU
;
‘
spring
(R)}
if
housing
ee
frame
(R)
Drive
gear
arm
‘
shaft bearing
Worm wheel ass'y
Figure
1-10.
;
2 >
Drive
gear
{R)
4.
Attach
the
worm
bracket
to
the
worm
shaft
Vex
spring
shaft
assembly.
Place
them
onto
the
boss
on
the
(Drive
gear
bottom
view)
cassette
housing
frame
(R).
.
Drive
gear
|
Note:
:
:
spring
(R)
five
gear
arm
insert
©
before
screwing
into
@
and
©.
(b)
Figure 1-12.
Cassette housing frame (R} 1
_Pass
the
tip
of
the
drive
gear
spring
(R)
@
through
the
square
hole
of
the
drive
gear
(R)
to
Switch
lever
hook
the
spring
in
position.
2.
Hook
one
end
@
of
the
reciprocating
spring
to
the
catch
of
the
drive
gear
(R).
3.
Hook
the
other
end
@
of
the
reciprocating
spring
to
the
catch
of
the
worm
wheel.
4.
Insert
the
pillar
@
of
the
drive
gear
(R)
into
the
B
tight
screw
;
square
hole
of
the
worm
wheel.
Turn
the
worm
‘\
wheel
somewhat
counterclockwise
for
insertion
of
the
worm
wheel
to
the
drive
gear
(R),
because
the
reciprocating
spring
is
at
work.
Worm bracket
©)
G)
Cassette
housing
frame
(R)
boss
Figure 1-11.
1

VC-90ET
ce
OF
CASSETTE
LOADING
BEL
\¥
Worm shaft ass‘y
(1) Start sensor PWB
Cassette
housing
frame
(R)
(2)
Worm
bracket
Figure 1-13.
1. Remove the start sensor PWB @ and worm
bracket @ from the cassette housing frame (R).
2. Remove the worm shaft assembly @).
3. Replace the cassette loading belt @ with a new
one.
Notes:
1. Do not overtighten the B tight screw which holds
the worm bracket in position. The specified
torque is 5.0 + 0.5kg-cm.
2. Make sure that the cassette loading belt is free
from grease. If stained with grease, clean the
belt with the cleaning liquid.
3. Perform checking of the clutch switch lever for
proper action.
CHECKING THE CLUTCH SWITCH LEVER
@ Checking
Place the mechanism in the cassette eject mode
when removing and attaching the cassette housing
from and to the mechanism chassis.
Make sure enough that each part in the cassette
housing such as the clutch switch lever is in
position. If not, it causes malfunction.
Note: ;
Figure 1-14 shows the position of each part in the
cassette eject mode.
Switch lever
Clutch
Worm shaft
lever
Rib of cassette Clutch lock fever
housing frame {R)
Rib
Drive gear
Figure 1-14.
Clutch release
12
1. First make sure that the tip of the switch lever is
held at the rib of the drive gear (R).
2.
Check
that
the
rib
of
cassette
housing
frame
(R)
and
the
concavity
of
the
clutch
lock
lever
are
engaged.
3.
Finally
be
sure
that
the
relationship
between
the
clutch
lever
and
the
clutch,
as
well
as
between
the
clutch
and
the
pulley,
are
correct
as
in
the
Figure
1-15.
Clutch Coupling
Ge
Worm shaft ——— A
Clutch lever X Pulley
Check
that
the
clutch
is
engaged
with
the
pulley
through
the
coupling.
Figure 1-15.
@ Resetting
Take the following steps to reset the clutch if it is
unlocked or if the switch lever and the clutch lock
lever are unlocked.
mauenteves Clutch tock lever
Rib of cassette housing frame (R}
?
Driver gear (R)}
Figure 1-16.
1. Shift the slider by turning the coupling in the
arrow direction (clockwise) until the slider pin is
at the bottom of the slider groove as shown in
the Figure 1-16. (The loading mode)
Note: Note that the slider is equipped with a
lock mechanism. Unlock the locks on
cassette housing frames (L) and (R) side
before shifting the slider.
2. When the position is set as shown in the Figure 1-
16, push the clutch release lever in the direction
of the arrow by hand until the clutch lock lever
becomes tightly locked by the rib of cassette
housing frame (R).
3. Then turn the coupling counterclockwise until
the slider reaches the cassette insertion opening
and the reciprocating spring is activated.
Note: There is no need to unlock the slider when
shifting the slider to the cassette insertion
opening. Just keep shifting the slider.
Clutch release leve

REPLACEMENT OF LOCK RELEASE LEVER
ASS'Y
@ Removal
1. Place the slider in the cassette down position.
(Turn the coupling on the worm shaft clockwise
until the slider is in the cassette down position.)
Note: Before shifting, unlock the slider.
2. Slightly widen the cassette housing frames (R)
and (L) to unhook the slider holders (R) and (L) of
the slider assembly off the grooves of the
cassette housing frames.
a a =,
Pulley
(a)
Cassette housing
frame (R)
housing
frame (L)
\ \
\
2
“BEM ye
Tobe BOW To be widened.
widened.
Slider holder (R) Slider holder {L)
Slider
(b)
Figure 1-17.
3. Lift the slider holder (R) upward about 2mm off
the slider by pressing two catches with a thin tip
screw driver. Take care not to damage the
catches.
Slider lock catch
Slider holder (R)
Pin
Slide it upward
Slider about 2mm
Catch
Catch Press here.
Lock release lever
z
--J
!
a]
!
Press here. i
H
'
'
1
Lock release lever spring
Figure 1-18.
VC-S0ET
4. Remove the lock release lever from the slider
holder (R)
@ Reassembly
. Follow the steps for removal in the reverse order.
(See Figures 1-17 and 1-18.)
2. Attach the lock release lever to the slider holder
(R).
3. Slide the slider holder (R) downward so that the
two catches of the slider holder (R) fit the
opening of the slider.
4. Slightly widen the cassette housing frames, and
set the pins of slider holders (R) and (L) into the
grooves of the cassette housing frames.
Note: Check if the pins of the slider holders (R)
and (L) fit the grooves of the cassette
housing frames, and if the drive gear arm
is sufficiently engaged with the slider
holders.
5. Turn the coupling counterclockwise until the
slider is at the cassette insertion opening.
_
TO RUN A TAPE WITHOUT THE CASSETTE
HOUSING CONTROL ASSEMBLY
. Plug in the power cord.
. Turn on the power switch.
. Open the lid © of a cassette tape by hand.
. Hold the lid with a piece of vinyl tape @.
. Set te cassette tape in the mechanism chassis.
. Weight the cassette tape with a weight @ to
prevent float.
7. Perform running test.
Am fwWwn —
Vinyl tapes
Weight to prevent (a
floating (500 g) rs
ZO
¢ a oa
"Mechanism chassis
/£
Note:
The
weight
should
not
be
more
than
500
g.
Figure 1-19.

VC-9O0ET
REPLACEMENT AND HEIGHT CHECKING
AND ADJUSTMENT OF REEL DISKS
@ Removal (Take-up reel disk)
1. Unscrew the screw © and remove the take-up
reel retainer.
2. Release the take-up reel disk catch ©.
3. Pull the take-up reel disk @ upward.
1. Remove the cassette housing control assembly. |
2. Set the mechanism in the playback mode with no
cassette tape in place. Unplug the power cord.
3. Set the idler gear in the center (neutral).
@ Removal (Supply reel disk)
1. Remove the tension band @. (Take care not to
deform it.)
2. Unscrew the screw @ and remove the supply ree] —sTake-up reel disk 4
retainer assembly ©.
3. Release the supply reel disk catch and back screw ss
tension lever @. t ©¥ cee
4. Pull the supply reel disk upward. ae
Notes : ‘wad
1. Take care not to deform the tension band. Take-up reel
2. Check and adjust the tension pole position. (See retainer
page 19.) ©
3. Be careful not to damage the gear and the idler
gear on the supply reel disk.
4. Press the tension band in the direction of the
arrow for removal (See Figure 1-20(b)).
Figure 1-21.
Reassembly (Supply reel disk)
. Clean the reel disk shaft D and apply oil to it.
. Release the supply reel disk catch @ and back
tension lever @.
. Install a new supply reel disk © onto the shaft.
. Replace the tension band © around the supply
reel disk, and insert it to the hole of the tension
arm.
Screw 5. Replace the supply reel retainer assembly © in
place, and tighten up the screw ®.
Notes : ;
1. Take enough care not to deform the tension
band during installation of the supply reel disk.
2. Be careful not to damage the supply reel disk
gear, back tension lever, catch, or the like with
tools.
bw N-— @
oF Supply reel
retainer ass’y
Supply reel disk catch
Back tension lever
(a)
{o=
ft
SSS,
dy
Supply
reel
pS 5 retainer as;"y
(3) Supply reel disk catch
Back tension lever
Figure 1-22.
(b)
Figure 1-20.

@
Reassembly
(Take-up
reel
disk)
1.
Clean
the
reel
disk
shaft
D
and
apply
oil
to
it.
2.
Release
the
take-up
reel
catch
@
and
video
search brake lever @.
3.
Install
a
new
take-up
ree!
disk
@
onto
the
shaft.
4.
Replace
the
take-up
reel
retainer
©
in
position
and
tighten
up
the
screw
©.
Note :
Take
care
not
to
damage
the
video
search
brake
lever.
Clean the reel disk shaft well,
and apply oil to it.
Take-up reel disk i
IW f
Take-up reel disk
catch
Take-up reel
retainer
Video search
brake lever
Apply a thin tip driver to the arrow position in
releasing for easier setting of the take-up reel disk.
Figure 1-23.
*
After
reassembly,
check
the
video
search
rewind
back
tension
(See
page
18),
and
check
the
brake
torque
(See
page
20).
Height checking and adjustment
Note:
Place
the
master
plane
onto
the
mechanism
unit,
taking
care
not
to
hit
the
drum
(See
Figure
1-24)
Setting
Reverse
guide
Cassette lock
release shaft
Jake-up reel disk
Figure 1-24.
Positioning
VC-SOET
Reverse quide
Master plane
Figure 1-25.
1. For height adjustment, press the reel disk with a
finger, and turn it right and left with a
screwdriver (See Figure 1-26 (a)).
Check that the reel disk is lower than part A but
higher than part B. If the height is not correct,
adjust the height adjusting screw (See Figure 1-
26 (b)).
Note :
Whenever replacing the reel disk, perform the
height checking and adjustment.
2.
Slide it right and left.
and check contact with .
the reel disk.
~Gpomesp-
ls
!
Reel disk height
Msterplane
adjusting-Jig
-
~tanse kewee
ma é
10+£0.2mm | Reel disk | r Mechanism chassis
Reel disk
(b)
Figure 1-26.
15

| V¥C-90ET
CHECKING AND ADJUSTMENT OF TAKE-UP
TORQUE IN FAST FORWARD MODE
@ Remove the cassette housing control assembly.
® Setting
Torque gauge
Set the scale to °'0’’.
F Setting
Take-up reel disk
Se
Figure 1-27.
@ Checking
Turn the torque gauge slowly
(one rotation every 2 to 3
seconds) by hand in the
take-up direction
The gauge is held at
its maximum value.
(Red mark)
x we Take-up direction
Figure 1-28.
®
Adjustment
1.
If
the
take-up
torque
is
outside
the
range,
clean
the
capstan
D.D.
motor
pulley,
reel
belt
and
reel
pulley
with
cleaning
liquid,
than
recheck
the
torque.
2.
If
the
take-up
torque
is
still
out
of
range,
replace
the
reel
belt.
Notes:
1.
Hold
down
the
torque
gauge
so
that
it
may
not
fly
off.
2.
When
checking
the
take-up
torque,
do
not
keep
the
reel
disk
locked
for
a
longer
time.
1K
CHECKING AND ADJUSTMENT OF TAKE-UP
TORQUE IN REWIND MODE
@ Remove the cassette housing control assembly.
@ Setting
Torque gauge
Set the scale to ‘’0'’.
Figure 1-29.
@ Checking
Turn the torque gauge slowly
{one rotation every 2 to 3
seconds) by band in the
take-up direction
700g:cm or more
The gauge is held at
its maximum value.
(Red mark)
Figure 1-30.
@ Adjustment
1.
If
the
take-up
torque
is
outside
the
range,
clean
the
capstan
D.D.
motor
pulley,
reel
belt
and
reel
pulley
with
cleaning
liquid,
then
recheck
the
torque.
2.
If
the
take-up
torque
is
still
out
of
range,
replace
the
reel
belt.
Notes:
1.
Hold
down
the
torque
gauge
so
that
it
may
not
fly
off.
2.
When
checking
the
take-up
torque,
do
not
keep
the
reel
disk
locked
for
a
longer
time.

CHECKING AND ADJUSTMENT OF TAKE-UP
TORQUE IN PLAYBACK MODE __ .
1. Remove the cassette housing control assembly.
2. Open the lid of the cassette torque meter, and
hold it with a piece of vinyl tape.
Vinyl tapes
Set value LP 95 +30g.cm aN
? 7
. ¢
Figure 1-31.
@ Checking
1. Check that the torque is in the range of 95 + 30
g.cm.
2. The torque fluctuates due to the rotational
deviation of the reel drive unit. Use the center of
the fluctuation as the value.
3. Place the unit in the LP record mode, and check
that the take-up torque is within the range.
@ Adjustment
If the take-up torque in the playback mode is
Outside the range, replace the take-up reel disk.
Note :
Weight the cassette torque meter to prevent
floating.
Place the torque gauge on the supply 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
170+ 40 g-cm.
17
VC-390ET
CHECKING AND ADJUSTMENT OF TAKE-UP
TORQUE IN VIDEO SEARCH REWIND MODE
@ Remove the cassette housing contro! assembly.
®@ Checking
Push the play button to place Push the video search rewind
the unit in the playback mode. button to place the unit in the
video search rewind mode
Torque gauge
Supply reel disk
Figure 1-32.
‘ Note:
Set the torque gauge securely on the supply reel
disk. If it is not secure, the measurement will be
incorrect.
@ Adjustment
If the take-up torque in video search rewind mode
is outside the range, replace the supply reel disk.
Note:
The torque fluctuates due to the rotational
deviation of the supply reel disk. Use the center of
the fluctuation at the value.

VC-9OET
CHECKING
THE
FAST
FORWARD
BACK
TENSION
@
Remove
the
cassette
housing
control
assembly.
e@ Checking
Place the unit in the
fast forward mode.
; eee reel disk
eect ie
Place
the
torque
gauge
on
the
supply
reek
disk,
and
turn
it
clockwise
very
slowly (one rotation every 2 to 3 seconds)
and
check
that
the
torque
is
within
15+5 g-cm
Figure 1-33.
Note:
Set
the
torque
gauge
securely
on
the
supply
reel
disk.
If
the
torque
gauge
is
not
securely
set
on
the
reel
disk,
measurement
will
be
incorrect.
CHECKING
THE
REWIND
BACK
TENSION
@
Remove
the
cassette
housing
control
assembly.
@ Checking
Ye)
7 Place the unit in the
rewind made. .
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 15+ 5 g-cm.
Figure 1-34.
Note:
Set the torque gauge securely on the take-up
reeldisk. If it is not secure, the measurement will be
incorrect.
Take-up reel disk
IR
CHECKING
THE
VIDEO
SEARCH
REWIND
BACK
TENSION
@
Remove
the
cassette
housing
control
assembly.
@ Checking
ite,
= -lpLay|- =»
ae
vey
7
Push the play button to place Push the video search rewind
the unit in the playback mode. button to place the unit in the
video search rewind mode.
at
Th
a
Take-up reel disk Gi
wv
mp |vse| mp
“TUN.
Torque gauge
Place the torque gauge on the take-up ree!
disk, and turn it couterclockwise very slowly
fone rotation every 2 to 3 seconds) and check
that the torque is within the set value
45+ 20 9-cm.
Figure 1-35.
Note:
Set the torque gauge securely on the take-up
reeldisk. If it is not secure, the measurement will be
incorrect. ;
CHECKING THE PINCH ROLLER PRESSURE
@ Remove the cassette housing control assembly.
gules
> ow >
<7 TNS
Push the play button to place the
unit in the playback mode.
Tension gauge
1,000-1,200 g
Use a finger.
Pinch roller
Capstan
shalt
Tension
gauge
adap!
er
Figure 1-36.

_ Detach the pinch roller from the capstan shaft.
2. Set the tension gauge by hooking the tension
gauge adapter onto the pinch roller shaft.
3. Gradually release the pressure to allow the pinch
roller to touch the capstan shaft. When the
pinch roller just touches the capstan shaft, read
the indication on the gauge.
4. Check that the reading of the tension gauge is in
the range of 1000 to 1200 g.
CHECKING AND ADJUSTMENT OF TENSION
POLE POSITION
e@ Remove the cassette housing control assembly.
—_
e Setting
Vinyl tapes
uul,.
o> [rec]: =>
a
ac: the unitin
the record mode.
Cassette tape
(E-180)
Mechanism chassis
(a)
Guide roller A ic) suide roller.
YD
F.E. head i
Supply \
impedance F
roller
A cgth |" \ Tension arm Vinyl tapes
AX : poe
Check the leftside
position (by
sight).
Tension band“[)
and plate
adjusting ji :
se
ting
Peay
Video
cassette
tape
(E
-
180)
(b)
Figure 1-37.
@ Checking
1. The guide rollers (A, B) operate to bring the tape
outside the cassette tape and simultaneously the
tension pole moves to the left, loading the tape.
At that time (loading completed), check the
position of the tension pole.
19
VC-S90ET
2. At the beginning of the tape (E-180), check that
~ the tension pole’s left side is aligned with the
supply impedance roller’s center by sight.
3. Check that the end of the tape is neither curled
against the flange of the supply impedance
roller nor over it.
4. During the video search rewind mode with no
cassette tape in place, check that the supply reel
disk is free from the tension band.
@ Position adjustment (record mode)
When the tension pole is at the right of the supply
impedance roller’s center:
Untighten the tightening screw, and shift the
tension band adjustment bracket in the direction of
the arrow using a tension band and plate adjusting
jig until it is in the set value range (center). Then
secure it with the tightening screw.
7 Center
_- Supply impedance roller
Tension pole
Tension band
ue Center and plate
Supply adjusting jig
impedance
roller
Tension
pole
Tension arm
Tightening
When the tension
pole is at the right
of the supply
impedance roller’s
center: ?
Tension band adjustment bracket
Figure 1-38.
@ Position adjustment (record mode)
When the tension pole is at the left of the supply
impedance roller’s center:
Untighten the tightening screw, and shift the
tension band adjustment bracket in the direction of
the arrow using a tension band and plate adjusting
jig until it is in the set value range (center). Then
secure it with the tightening screw.
a Center
! Supply impedance roller
Tension pole
Tension band
a Center and plate
adjusting ji
1 Supply ie Tension arm
impedance
roller . ;
Tension Tightening
pole
Supply reel
disk
Figure 1-39.
Fie Roe SSSR ea SE ee Na A a eae

VC-90ET
CHECKING
AND
ADJUSTMENT
OF
RECORD
/
PLAYBACK
BACK
TENSION
A. When using a cassette torque meter:
Remove the cassette housing control assembly.
Checking
Weight of 500g
Cassette torque meter
: Push the record button
to place the unit
in the record mode.
Figure 1-40.
1.
Put
acassette
torque
meter
into
the
unit.
2.
Push
the
record
button
to
place
the
unit
in
the
record mode.
3.
Check
that
the
back
tension
indicated
by
the
gauge
is
within
the
set
range
31
to
36
g.cm.
Notes:
1.
Make
sure
that
the
video
cassette
tape
is
over
the
retaining
guide.
2.
Make
sure
that
the
tape
is
not
slack
nor
damaged
at
either
end.
@ Adjustment
1. If the reading of the cassette torque meter is less
than specified, move the tip of the tension spring
hook plate toward the hole A.
2. tf the reading of the cassette torque meter is
more than specified, move the tip of the tension
spring hook plate toward the hole B.
Put a thin screw driver (-) in the shaft hole, lean
it toward you, and turn it for easier shift of the
tension spring hook plate in the direction of A or
B.
x
Tension
spring
gu
Hole A
Tension spring
hook plate
Figure 1-41.
Tension spring hook plate
an
Figure 1-42. Not used.
CHECKING THE BRAKE TORQUE
@ Checking the brake torque at the supply side
Supply
reel disk
ar
CW: 280-720g-cm
CCW: 90-230g:cm
Adjust the idler gear
Mechanism chassis in the center
Figure 1-43.