Dual CS 626 Service Manual

Direct Drive System Dual EDS 500
For repair of the Dual EDS 500 special tools and measuring
means are required. Work on
the motor or motor electronics
system should,
therefore, only be carried out by an authorized
Dual service stet ion.
Replacement of motor electronic
1. Extract unit plug from power line. Lift off platter 4. Remove
the machine screvv and the monting
plate 27. Loosen connec-
tion on solenoid plate 151. Clamp unit in
repair jig. Bring
unit into
head position.
2.
Loosen connection for operating voltage
on electronic plate
137. Unsolder
connecting leads on speed control 157, turn
switch 6 and generator.
Open twists of holding angle 142
with
flat
pliers.
3.
Pull off motor electronics 143
system from motor 141
carefully.
4. Fix
replacement
motor
electronics.
Solder
connecting cables (see
connection diagram Fig.
5. With
the unit in normal position connect it to
power line.
Switch on
unit and check power
consumption on
Operation:
220
V/50
Hz
approx. 15 mA
110 V/60 Hz approx. 25 mA
Check
nominal speeds. If necessary,
readjust as described
belovv.
6. Bring unit in the base.
Install the platter 4. Mounting plate
27
fix
it with
machine screws.
Fig. 7
123
137
Fig. 8
• 1 ffl 11131
Ondluldschelter
Plmer I.* switch
Commutateur de v.u.,
Eldbaron
Elearonm
Elderond.ue
143
140
7
8
142
Replacement of motor mechanic
1.
See abore. Clamp unit
in repair jig.
2. Unsolder connecting leads to motor and the generator. Open
twists of holding angle 142 with flat pliers. Lift off motor
electronic 143.
Removemachine screw and holding angle 142.
3. Loosen threaded pins 8 and remove platter cone 7. Remove
the
three screws 140. Lift off motor
mechanics 141.
4. Put platter cone 7 on new motor mechanics and
fix it. Fix
new motor mechanics
with the
three
screws 140. Fix holding
angle 142 with screws. Insert
motor electronics 141 and twist
holding pieces.
Solder on
resp. plug connecting
leads (Fig. 8).
5. With
the unit in normal position
connect it to the power line
Switch on unit and check power
consumption when opera-
ting:
220
V/50 Hz approx. 15 mA
110
V/60 Hz approx. 25 mA
Check
nominal speeds. If necessary,
readjust as described
below.
6. Bring unit in the
base. Install the plater 4. Mounting
plate 27
fix it with machine screws.
Setting
nominal
speeds
With
knob 10 bring the fine speed
control 157/R 19 into center
position. With controls R 8
and R 9 on the motor
electronic
system adjust nominal
speeds. Control R 8 is used for 331/3
rpm,
R 9 for
45 rpm. Check with
strobe disk.
Changeover to 78 rpm
nominal speed
lnstead of 45 rpm the can be
changed to a nominal speed of
78
rpm.
To
change the speed bring the
fine speed control 157/R
19 in
center position using
knob 10. Using control R 9
on the motor
electronics
board 143 adjust for 78 rpm.
Check with strobe disk.
Stroboscope
Accurate setting of the
platter
speeds
33 1/3
and 45 rpm can be
checked
during
play with the
aid of the
stroboscope.
When the platter 4 is rotating at
exactly 33
1/3
or 45
rpm the
lines of the
stroboscope appear to stand
still. If
the lines move
in
the direction
of rotation of
the platter, the
platter speed is
too
high. If the lines move
backvvards, the
platter is
rotating more
slovvly than the
nominal speed.
Adjustment of
platter speeds
33 1/3 and
45 rpm can make
with the "pitch"
control 10.
Strobe
markings are provided on the
outer
edge of the platter
for
50 and 60 Hz line frequencies.
To replace LED
154 remove
machine screws 156 and
remove
strobe cover 153.
lt can
happen that the
stroboscope lines
appear to move slightly
although the
exact speed setting
with stroboscope
stationary has
not been
altered. This
apparent contradiction is
explained by the
fact that
the electronic
central drive motor
operates fully inde-
pendently
of line frequency
whilst the only
relatively accurate
line frequency of the AC
current supply is used
for speed
measurement
with the light
stroboscope. The constantly detec-
table fluctuations of line
frequency by
±
0.2% according to the
information of the electricity
supply companies brief
frequency
fluctuations up to 1 % are
possible — only effect the stroboscope
indication and can
cause the lines to "wander" although
the
platter speed is as
constant and absolutely accurate as before.
Pitch Control
Each of
the two standard speeds 33 1/3
and 45 rpm (78
rpm)
can be varied by about 10 %.
The variable speed control 157/R 19
located in the voltage divider is
adjusted by turning the pitch
control knob 10. By this the differential amplifier is
altered and
the motor speed accordingly.
6

Dual CS 626 Specifications

General

Brand	Dual
Model	CS 626
Category	Turntable
Language	English