Dokorder 7700 - Reel Motor Torques

(1)
Read
the
pressure
indicated
on the spring
balance
when
the
pinch
roller loses
contact
with the
capstan and the
pinch
roller stops
revolving
(2)
Adjust the
pressing
force
of the
pinch
roller by
turning
the
nut
@
and
@,
if nec.ssaty.
rY
g
Note
(1)
Use a
precision
spring
balance
with a scale of up
to
4 kg
graduated
in
steps
of 50
g
or less.
(2)
Loosen lock
nut first before attempting
step
f-(2).
(3)
Fix
the
adjusting
nut
@
with the
lock nut
@
and then
paint-lock
it.
5-3 REEL
MOTOR
TOROUES
2-2
PINCH
ROLLER
PRESSURE
a. Specification
1
'5
ks
tQ"l
Pg
r.t
b.
Adlustment
Adjust the
pressure
adjusting
nut
@.
c.
Reference
Refer to
Fig.
5-3
or
section
2 on
page
M-20.
d. Special
Tools andlor lnstruments
required
A open
end wrench
(4
mm) and spring
balance
(4
kql'
e.
Preparation
Remove the front
panel
(including
pinch
roller
and
head cover).
Fix
the
auto
shut-off
arm ON
by a
piece
of
stickinq tape.
f. Procedure
a. Speci{ication
y
Hold-back
Tension
85
gr
110 gr
(255
+30
g.
cm)
Take-up
Torque 150
gr
(450
g.
cm)
b.
Adjustment
Adjust the
wirewound resistor
R-2
(150
ohm)
for
the
hold-back
tension.
c. Reference
Refer to
Fig.
5 4, 5-5 or section
2
on
page
M-22.
d.
Special
Tools and/or
lnstruments
required
A spring
balance
(200
q)
and
7-inch small-hub
reel
ry
(6
cm in diameter).
e.
Preparation
Remove the back and top
boards.
Fix the auto shut-off
arm ON
by a
piece
of
sticki
ng taPe.
f. Procedure
f-i.
Hold-back
tension
(Playback)
(1
)
Mount the 7-inch
reel on
the
left
turntable
with
a
piece
of string
attached to
it, as shown
in
Fig.
5-5
(A).
(2)
Set
the deck in
play
mode and
pull
the spring
balance
gently
in the
direction
indicated
by
the arrow in
F ig.
5
5
(A)
and read the
indicated figures on the spring
balance.
(3)
Loosen lock screw
@
securing
the slide ring
O
on the
R-2 in Fig. 5-4 and
adjust the
position
of
the slide
ring so that the spring
U
balance indicates
85
g 110
9
(255
g.
cm
130).
f-2. Take-up torque
(Playback)
Pinch Roller
Capstan
Shaft
Capstan
Bearing
Fig.5-3
\Pinch
Roller Arm
@stioe
ning
@Lock
Screw---
lncrease{--
--->Decrease
Fig.5-4
"Moror
chasis
/^-\-i
\ t)---< )
,
\,fo
oo\.,"
q\
4.^/
\\\//
tlo \ /
\\ \ / /
\ L-/ ,,',
F ig.5-5
(1)
Mount
the
7-inch reel on the
right turntable with a
piece
of
string
attached to
it. as shown
in
Fig.
5-5
(B).