Dual 604 User manual

Dual
Edition
February
1978
60
1 1
Service
-
Manual
Dual Gebrüder
Steidinger •
7742
St.
Georgen/Schwarzwald
Download from www.dual.de
Not for commerical use

Contents
Page
2
3/4
5
6
6
6
7
7
7
7
8
8
8
8
9
9
9
9
10
10
10
10
11
11
11
11
11
11
11
11 —
17
18
Technical data
Current
Line voltage
Drive
Power input
Power consumption
Time from
start to rated speed
Platter
Platter
speeds
Pitch control
Speed control (monitoring)
Technical data
Wiring
diagram
Audio
connection diagram
Dual EDS 500
electronic direct
drive system
Replacement of motor
electronics
Replacement
of motor mechanic
Adjustment of nominal
speeds
Setting
78 rpm nominal
speed
Stroboscope
Pitch
control
Tonearm and
tonearm
suspension
Removal of
tonearm from bearing frame
Removal of tonearm compl.
with
tonearm suspension
Removal of
spring housing
Adjustment of tonearm
suspension
Antiscating control
Cue control
Replacement of cue control assembly
Tonearm
control
Adjustment
point
Muting switch
Starting and
shut-off
Adjustment points: Segment/power switch
Pick -up
head not parallel
Stylus
slips out of
playing groove
Tonearm does
not set down or lowers onto
record too
quickly
after
Tonearm moves
at zero position of
dials
Motor does not shutt-off when setting down on tonearm rest
Acoustic feedback
Replacement with exploded
views
Lubrication
Sensitivity of the illuminated strobe
(for
0.1 % speed
deviation)
Total
wow and flutter
Rumble
laccording to DIN 45
5001
Tonearm
Effective length of tonearm
Offset
angle
Tangential tracking error
Tonearm bearing friction
Stylus
pressure
Weight
AC 50 to 60
Hz
110 to
125V, 220 to
240V
electronically-regulated direct-drive system, Dual EDS 500
approximately
2 watts, Motor at playing Operation
< 50 mW
220 V 50
Hz: at start 25 mA
110 V
60 Hz: at play 15 mA
at
start 65 mA at play approximately
25 mA
2 — 2.5 s at
33 1/3
rpm
non-magnetic, dynamically balanced, detachable 1 3 kg, 300 mm diameter
33
1/3 and
45 rpm, electronically adjustable
Separate for both speeds, each adjustable by means of variable resistor,
with
calibration scale;
range of
regulation: 10%
with
illuminated
stroboscope for
platter speeds 33 1/3 and 45 rpm,
adjustable to 50 or 60
Hz.
6
division markings per minute at
50 Hz,
7.2 division markings per minute at 60 Hz.
according to
DIN 45 507 (German
Industry Standard)
< ± 0.06 %
Unweighted:
> 45 dB
Weighted:
>
65 dB
Torsional ly rigid tubular aluminum tonearm in
low-friction four-point gimbal
suspension, tonearm counterbalance with
two mechanical anti-resonance filters.
222 mm
25 0
20'
0.16
0 /cm
vertical <
0.07 mN
10.007
g)
horizontal
<
0.16 mN )0.016g)
from 0 to 30 mN 10 to 3
g) infinitely
variable with 1 mN-
11/10 g) calibrations
from 0 to 15 mN 10
to 1.5 g), operable from 2.5 mN
10.25 g) stylus pressure up.
4.6 kg
Dimensions
and
Cutout Required refer
to
Installation
Instructions.
(related to stylus
tip)
2

D
1
( - 1
—
ZPD
7,5
cl
47 p
2
• 66 2/3
Hz
(33
minl)
C
2
220 p
R2
10 k
C4
0,47 p
+
R 1
1
M
C
0,47 /I
Ti
R5
1 M
1—*
G 1
BC 172
R3
68 k
n 33
—t•
4
•
G2
R6 R4
22 k 82 k
C 5
— 10 n
C6
in
G3
—C 7
n
G4
R8
—
A 9
—10 k 22k
R7
47 k
R 10
24 k
T2
BC
172 B
—C8
0,22 p
Transistoren von der Anschlußseite gesehen
Transistors
as seen from the connecting side
Transistors vus
du cöte des connexions
• • e
BC
172
BC
238 C
IC
von der
Bestückungsseite gesehen
as seen
from the top
side
vu du
cöte
el6ments
555
EBC
4069
BD 415
1
4
2
3
1
2
3

R
16
8.2
•
7
15
2
8
4
6
IC
2 —
555 —
3
3
7
1
5
R
11
110k
6
R
19
2,5k
1 2
•
G5
G6
14
in
_C9
—
20 n
560
R
13
15 k
D2
1 N
4148
V
R
15
C 10
— 0,47 p
10
k
R
14
220 k
C
13
47 p
12
— 0,68 p
8.1
7 •
T3
BC 238 C
MIM
1.3
R
12
270 k
10/130
V-
20/240 V-
10 n
=-
12
C 11
+
10 p
R
18
2
R
17
47
k
Si 63
mAT
C
52-
47 n
220 V
C
51
—
68 n
A D 51
/ By 183
R
51
22 k
19
13 16
14 15
52
51 17
1
70 5
, 3 ,
18
10
13
T4
BD 415
20,5 V
C 55
1000 p
T54
0 n
14
9
52
11
51
4
12
53
54

Fig. 2
TA-Anschlußschema / Audio
Connection Diagram / Schema de
branchement /
Esquema de conexion del fono captor
L
a) mit DIN-Stecker 5-polig / with DIN-plug 5 pin
b) mit Cynchstecker / with phono plug
avec ficrie DIN 5 pöles / con enchufe DIN de 5
poles
rechter
Kanal
right channel
canal droit
canal
derecho
rot / red /
rouge / rojo
linker
Kanal
left
channel
canal gauche
canal
izquierdo
weiß / white / blanc
/
blanc
rechter
Kanal
right channel
canal droit
canal
derecho
rot / red / rouge / rojo
[1
ni
,
Masse rechter Kanal
Mass right
channel
1
Masse
canal
droit
1
masa canal
derecho
grün /
green /
vert /
verdc
1
1 1
L J
!
I
i
1 I
1 I
I 1
1 I
loi
1 I
1
1
\
Tonabnehmerkabel
Tonearm
audio cable
Cäble
de
BF
Cable del
fonocaptor
avec fiche cynch / con enchufe Cynch
rechter Kanal / right channel- 1 -
Canal droit / Canal
derecho
rot
(schwarz) / red
(black)
rouge (noir) /
rojo (negro)
Masse draht / Mass lead
Mass cable
/
Mass
cable
_
1 - 1
linker Kanal
left
channel
1 canal gauche
canal izquierdo
-I-weiß
/ white / blanc /
blanco
1 Masse
linker
Kanal
1
Mass left
channel
1
Masse
canal
gauche
1
masa
canal
izquierdo
j blau
/ blue /
bleu /
azul
-
z 1
i i
•. 1
'1 1
—
1
Masse rechter
Kanal - 1
Mass right
channel 1
Masse canal droit
masa canal derecho
I
/ / /
II I I
I
1
Masse schwarz
Mass black
Masse noir
Masa
negro
7
Masseblech
Mass
sheet
Prise de
masse
chapa
de
masa
Kontaktplatte
Contact plate
Plaque de contacts
Placa de contacto
I
-r -linker Kanal / left
channel
I 1
Canal
droit /
Canal
izquierdo
I 1
gelb (weiß) /
yellow (white)
jaune
(blanc)
/ amarillo
(blanco)
I I
fl
I 1
1
I
- -
-- 1 1
Cynch-Tonabnehmerkabel
I
1
Pick
-up lead
with
Cynch
plug
Cäble de BF avec fiche Cynch
Cable del fonocaptor con
I
enchufe
Cynch
I ---
Masse linker Kanal
Mass left
channel
Masse canal
gauche
1 1
masa canal
izquierdo
I
7-•
II 1 15 I
-
I
L
/ / 7 7
L ,
[1
1 Kurzschließer
1 Muting switch
1
Court-circuiteur
i 1 Dispositivo
cortocircuitador
I II I I
Tonarm kopf
Tonearm head
Tate
magnätique
Cabezal
fonocaptor
5

Fig. 3
Direct
Drive System Dual
EDS 500
Fig. 4
Dr.ahlechalter
Platter speed welch
Demreutatem de ritere
Netateil
l ' eT 4
Fig. 5
Netzteil
Supply
unit
Bloc
secteur
Generator
Generateur
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 station.
Removal
1.
Extract unit plug from
power line. Lift off platter
(4).
Bring
unit into head position.
2.
Remove
machine
screws
(112) and
cover of
power part
(113).
3.
Unsolder
connecting leads
to motor
and
generator. Open
twists
of holding
angle
(150) with
pliers.
Remove
motor
electronics (152),
screws (151)
and
holding
angle
(150).
4. Pull off motor electronics (152) system from motor (18) care-
fully.
5. Fix
replacement motor
electronics.
Solder
connecting cables (see
connection diagram Fig. 4).
6. Slide cover
over power part and fix it by
means of machine
screws (112).
7. With the unit
in normal position
connect it to power
line.
Switch on unit and
check power
consumption on
Opera-
tion:
220
V/50 Hz approx. 15 mA
110
V/60 Hz
approx. 25 mA
Check nominal speeds. If
necessary, readjust
as described
below.
Replacement of Motor Mechanics
1. Extract
unit plug from power
line. Remove platter
(4).
2. With the
unit in head
position remove
machine
Screws
(174)
and washers
(173). Pull off motor electronics board (172)
together with cover (175)
carefully from the motor
(18).
Drehzahlregler
/ R 19
Platter
speed
switch / R
19
Commutateur de
vitesse / R
19
R1
r i
1.2
3.1
Cl
) 1.3
•-ig2-4,
-
Motor
Moteur
8.2
Pol* el
R6 1 -•
3
Ti T
C13
-,-
6-1 R13
I-•
jC11 4
e
_p_±.
)2
7 8
T2
•
•
02
IP-
WM f
12
2IC2
e
C7 C8
1. _
)
11 T
-A.C5
•_ii_.
- 1 -- cloib
li p:.
-T
1
*-1
R15
1-•
T3
6

3.
Loosen connection for operating voltage at het
plate (109).
Unsolder connecting leads to speed fine adjustment (129),
rotary switch
(5) and the generator. Open twists of
holding
angle (152)
with pliers.
4. Loosen threaded
pins (36)
and remove platter
cone (35).
Remove the three screws
(148). Lift
off motor mechanics
(149).
5. Put platter cone (35) on new
motor mechanics and fix it. Fix
new motor mechanics with the
three screws (148). Fix holding
angle (150)
with screws (151). Insert motor electronics (152)
and twist holding pieces.
Solder on resp. plug connecting leads (Fig. 4).
Push
cover on
power part and fix lt
with screws
(112).
6.
With the unit in normal position connect lt 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.
Setting
nominal
speeds
With
knob
(7) bring
the
fine
speed
control
(129/R
19) into
center
position. With
controls (R 8)
and (R
9) on
the
motor elec-
tronic
System adjust
nominal
speeds.
Control IR 8)
is used
for
33 1/3
rpm,
R 9 for 45
rpm. Check
with
strobe
disk.
Changeover to 78 rpm nominal speed
I nstead of 45 rpm the Dual 604 can be changed to a nominal
speed of 78
rpm.
To
change the speed bring the fine
speed
control 1129/R
19) in
center
position using knob (7).
Using
control
R 9 on the motor
electronics board (172) 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 backwards, the platter is rotating
more
slowly than the nominal speed. Adjustment of platter speeds
33 1/3 and 45
rpm is carried out separately with the "pitch"
controls
(7).
Strobe markings are provided on the outer
edge of the platter
for 50 and 60
Hz line frequencies.
To replace glow lamp (157) remove machine screws (160) and
remove
strobe
cover (156).
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 ± 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 c,ause
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 178 rpm)
can be varied by about 10 %. The variable speed control 1129/
R 19) located in the voltage divider is adjusted by turning the
pitch control knob (7). By
this the differential
amplifier is
altered and the motor speed accordingly.
Fig. 6
153
144
156
157
159
160
Fig. 7
Netztrafo
Mains transformer
Transformateur de
rgiseau
C55
L537,
C52
. I—•-•
e R52
C51
.1
51
-- *
Z
-K-• R
51
.4=-4
fI
E3,4› ee
63
mA mT
0 223/
10V
Motor
Motor
Moteur
Glimmlampe
Glim
lamp
Lampe ä
effluves
7

194 68 42
60
202
Fig. 8
71
17
19
11 11 3 1
mmmmmmmmmmm
11111111 .uu.7 Iu.II" Piwassiouseinewe e i ' u1111111i
p. ›.. • •
•• • • • • • •
bl
'Luv
it_g_KAA I i m
'L!''. ir
I 3 ZZZZZZZZZZ II i
r. •
197
168
Tonearm and
Tonearm
Suspension
The
feather-light,
extremely torsion
resistant all-metal
tonearm is
suspended in
a gimbal.
Suspension is by
means of 4
hardened
and
precision polished
steel points
which rest in
precision ball
bearings. Tonearm
bearing friction is
thus reduced to
a minimum.
Bearing friction vertical
0.07 mN (0.007 p)
Bearing friction
horizontal 0.16 mN (0.016 p)
as related to stylus point.
As a result, it ensures
most favourable
pick -up conditions.
Before
adjusting
the tracking force
to suit the built-in
pick -up cartridge
the
tonearm is balanced
with the scale set
to zero. Coarse
adjust-
ment is carried out by
moving the weight with the stem
(49), the
subsequent fine
adjustment by turning
the weight. The
balance
weight is designed
such that pick -up
cartridges having a dead-
weight of 4.5 - 10 g can be
balanced.
The tracking force
is adjusted by
turning the graduated
spring
housing (60)
incorporating a coil
spring. The scale has
markings
for a range
of adjustment from 0 to 30 mN
(0 to 3 p) which per -
mit accurate
adjustment of the
tracking force. One
graduation in
the range of 2 - 15 mN
(0.2 - 1.5 p) corresponds
to 1 mN
(0.1
p),
in the range of 15 - 30 mN (1.5 - 3 p) to
2.5 mN (0.25
p).
Fig. 9
208
211
207
206
43
185
34 57
49
219
205 206 203 2 2
11 207
Removing the tonearm froM the bearing frame
We recommend the following
procedure:
1. Clamp unit in the repair stand. Set spring housing scale (60)
to zero. Lock
tonearm
(48). Remove weight (49).
2. Turn unit over
and remove the screening sheet (140). Un-
solder the
tonearm
connections
on the
muting
switch
(137).
3. Remove safety washer (187), washer (186) and bearing (185).
Move
positioning bar
(219) towards muting
switch (137).
4.
Unlock tension spring (208), loosen safety washer (215) and
remove skating lever (214).
5. Remove
safety washer (212) and sliding washer (210)
and
take shut-off bar (161) from segment.
6. Remove hex nuts (210)
and segment
(207).
7. Hold
tonearm (48). Remove hex nut (203) and
tonearm cpl.
with tonearm bearing.
Reverse this procedure when reassembling.
Removal of
tonearm
assembly
with
tonearm bearing
1. Secure unit in repair jig. Remove
weight (49) and undo fixing
screw (52).
Set
tracking force scale (60)
to
zero.
2. Move unit into
head position. Remove
screening plate (140).
Unsolder
tonearm connecting on muting
switch (137).
3. Move
unit into normal
position. Remove
both mounting
screws - SW
4.5 (54).
For installation proceed in the reverse order.
Replacing
spring housing
Remove tonearm
(48) from bearing
frame (51) as
described
above. Loosen lock
nut
(55) and threaded
pin (56).
Unscrew
bearing
screw (61). Lift bearing
frame
(59). Remove
spring hou-
sing (60). When installing
rote that the helical spring
catches the
bearing frame. Slide
in washer (60) and
tighten bearing
screw
(61). Reinstall
tonearm (48). Set
bearing play as described
below
using
threaded pin (56) and
lock
nut
(55).
8

Adjusting the tonearm bearing
First balance tonearm
exactly. Both bearings must have slight,
just perceptible play. The horizontal tonearm bearing is correctly
adjusted when at anti-skating settings "0.5" and being touched lt
slides in without
resistance. The vertical tonearm bearing is
correctly
adjusted when
lt
swings in
after being touched. The
play of the horizontal
tonearm bearing
should be adjusted with
threaded
pin
133) and mat
of the
vertical
tonearm
bearing with
threaded pin
(56).
Anti-skating
Device
To compensate for skating force use the knurled ring (66). The
asymmetric cam
plate (217) displaces
the skating
lever
(214)
from
the
tonearm pivoting point. The
anti-skating force is trans-
mitted to
the segment 1207) and to the tonearm (48)
by
tension
spring
1209).
Optimum adjustment is carried out at the works for
styli having
a tip radius of 15 pm (conical), 5/6 and 18/22 I../m lellipticall,
and CD 4-cartridges.
Any
alteration can only be carried out with the aid of a
Dual
-
Skate -0 -Meter and a test record and should only be done by an
authorized service station.
Recheck as follows:
Balance tonearm (48) correctly. Set knurled ring (661 to 0. The
tonearm should remain at any desired point within its turning
range.
The hole
of the skating lever
(214) should be in alignment
with the center line of the tonearm. Adjustment is made by the
eccentric pulley (E) which is accessible
through the hole in the
installation
plate
(231
between the knurled ring (68)
and the
tonearm.
Then
set
knurled
ring
(66) to "0.5". The tonearm should now
smoothly
rotate from the platter
center to
its rest
(71).
Cue Control
By moving the lever
1194) forward I
•1 lift cam (197)
rotates.
The slide bar
(219) connected to lt transmits this
movement to
the
lift pin (206) (via the compensating
cam which then raises
the tonearm. As a result, the
cue control permits setdown of the
tonearm at any desired point.
The lever (194) is released
by moving the cue control
lever rear-
wards (I).
As a result of the action of
compression spring 12041
the lift pin
(201) is brought back to its
normal position and the
tonearm lowered slowly. Lowering of the
tonearm is damped by
silicone oil in the
lift
tube.
Adjustment Point
The lift height may be varied
by turning the sleeve (202).
The
distance between the
record and the needle is to be 5 - 7 mm
with the
tonearm 1481 having a height play of 1
- 2 mm
Make
adjustment by means of set screw (571.
Replacement of Cue Control Plate
Replace
cue control plate (201) es
follows:
1.
Clamp unit in the repair stand and
lock
tonearm. Turn unit
over.
2.
Remove
safety washer
(187), washer
(186) and
bearing (185).
Lift
positioning bar
(219) and move towards muting switch
(137).
3. Unlock tension spring (208). Loosen safety washer (215) and
lift skating lever (214). Remove safety washer (213) and sli-
ding bar (212). Lift shut-off bar (161) from segment
(207).
4. Remove
hex nuts (211) and segment
(207).
Fig.
10
Fig. 11
Fig.
12
9

5. Remove machine
screws (205). Hold tonearm
bearing.
Linscrew hex nut
(203) and remove lift plate
(201).
6. Secure tonearm with hex nut (203) against falling out.
Reverse this
procedure when
reassembling.
Tonearm set-down mechanism
When turning
knob (68) to "V"
position the recesses
of slide
bar (219) are positioned in the area
of the
spring pin (F) of seg-
ment
12071.
When moving slowly the tonearm
with tonearm cue control in
V position the
spring pin (F) is arrested in
the recesses of slide
bar (217) thus
designing the set-down point
of stylus for 30 cm
and 17 cm records.
To
enable set-down in the
catching range of
the arresting point
of the appropriate
setdown position, the
tonearm set-down
me-
chanism can be
disengaged with the knob (68) in "—" position.
Adjustment Points
a) Balance tonearm
(48) exactly.
Bring knob (68)
into
position. Let
tonearm catch in catch
point for tonearm set-
down point. Check catch
force by means of a spring
balance.
lt
should read 10 — 20 p. The
force is adjustable by means
of
a threaded pin.
b) The
tonearm set-down point can be
adjusted by turning set
screw (42).
Adjustment can be made for 17
-cm- and 30 -cm
records.
Short Circuiter
To prevent
disturbing noises during automatic
operation of the
tonearm the unit is fitted with a short circuiter. Control of the
switch springs for both channels is effected by the camwheel.
With the unit in neutral state the short circuit of
the pick -up
leads is eliminated.
Adjustment
In zero position of the cam there should be
a
clearance of ap-
proximately 0.5 mm
between the contacts of the
short circuiter.
This clearance
should be adjusted
by bending the short
circuit
contact. The contacts
should be sprayed with a
suitable cleaning
agent.
Starting
and shut off
Swing ing in the
tonearm
(48)
rotates the
segment (207)
thus actua-
ting the power switch (116) and shift arm
(146) and
starting
motor 11491 and platter (4) rotating.
The shut-off cycle after
playing a record is initated by the dog
(M)
of the platter 141 and shut-off
lever (A).
The shut-off lever (A) is guided onto the dog by
the movement
of the
tonearm when playing the record with
the aid of the shut-
off
bar (161) proportionate to the
groove lead (Fig. 13 a).
The
eccentrically-mounted dog forces the
shut-off lever (A) back
w,ith each revolution as
long as the advance
of the
tonearm only
amounts to the width of one
groove.
The
cam
wheel (37) is thus guided to the pinion
range of
the
platter. The tonearm is
lifted and the
resetting bar (188) trans-
ports it back to
the rest. The power switch is operated, thus
switch ing the unit off.
Fig. 13
207
Fig.
14
Fig.
15
219
0,2 mm
A
37
161
a.)
b.)
10