Dual CS 731 Q User manual

3
,••••••"-
"VI
'mag.
Dual
Edition April
1979
CS
731 Q
Service Manual
Dual Gebrüder
Steidinger
7742
St.Georgen/Schwarzwald
Download from www.dual.de
Not for commerical use

Fig. 1
TA-Anschlußschema / Audio
Connection Diagram /
Schema de
branchement /
Esquema de
conexion del fono
captor
a) mit
DIN-Stecker 5-polig / with DIN-plug 5 pin
b) mit
Cynchstecker / with phono plug
avec fiche 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
Neiß
/ white / blanc /
blanc
Stummschaltrelais
Silent
switch
relay
Relais -
conmutateur
silencieux
Relä de
conmutacion
silenciosa
rechter
Kanal
right channel
canal droit
canal
derecho
rot
/ red / rouge / rojo
Masse
rechter
Kanal
Mass right
channel
Masse
canal
droit
1
I I
I I
I
I
I
mass
canal
derecho
grün
/green /
vert / verdc , I
I
i
I
I
Tonabnehmerkabel
Tonearm
audio cable
Ca ble
de
BF
Cable del
fonocaptor
avec fiche cynch / con enchufe Cynch
rechter Kanal / right channel
---
Canal droit /
Canal derecho
rot (schwarz) / red
(black)
rouge
(noir) /
rojo
(negro) 1
IM R
E
I 1
I
L_I
1
I I
•
( - 1
I
I 1
'
14 1
1
I
I
I I
Masse draht /
Mass lead
Mass
cable
/
Mass
cable
1
Masse rechter Kanal - 1
Mass
right channel
Masse
canal
droit
mass canal derecho
Stummschal
trelais
Silent
switch
relay
Relais -
conmutateur
silencieux
Relä de
conmutacion
silenciosa
L
r -
1
•
•
f i
1 .
l inker Kanal
1 left
channel
1 canal gauche
canal izquierdo
4 -weiß / white /
blanc / blanco
L _
I
Masse
linker
Kanal
1 Mass left
channel
Masse
canal
gauche
mass canal
izquierdo
1
blau
/blue /
bleu /azul
Masse
schwarz
Mass black
Masse noir
Masa
negro
z//z z / /7 z
I
II
II
— - 4-
_
7 -linker
Kanal / left channel
Canal droit /
Canal
izquierdo
I gelb
(weiß) /
yellow
(white)
.
jaune (blanc)
/
amarillo
(blanco)
4. 1
Cynch-Tonabnehmerkabel
Pick -up
lead
with Cynch
plug
Ca ble de BF avec fiche
Cynch
Cable del fonocaptor con
enchufe
Cynch
I —
Masse linker Kanal
Mass left
channel
Masse canal
gauche
mass
canal izquierdo
0
Masseblech
Mass
sheet
Prise de
masse
chapa de
masa
Kontaktplatte
Contact
plate
Plaque de
contacts
Placa de
contacto
fi r
I 1
I
I 1
I 1
I I 1
1
I
I 1 1
i
I
I i
I
1
L.1 L 1
Kurzschließer
Muting switch
Court-circuiteur
Dispositivo cortocircuitador
/
/7/
/ / / /
I
II I
I
Tonarmkopf
Tonearm
head
Täte
magnätique
Cabezal
fonocaptor
2

Contents
Page
2
3
4
5
5
6
6
6
6
6
6
6
7
7
7
7
8
8
8
8
8
8
8
9
9
9
9
9
10
10
10
10
10
10
11
11
11
11
11
11
11
12—
15
16
Technical data
Current type
Line
voltages
Drive
Power consumption
Run -up time
Platter
Platter speeds
Pitch control
Speed check
Sensitivity of light stroboscope
for 0.3 % speed deviation
Wow
and flutter
Signal-to-noise ratio
Tonearm
Effective tonearm length
Offset
angle
Tangential track error angle
Tonearm bearing friction
(related to stylus point)
Tracking force
Pick -up
head
Cartridge
Weight
Tonearm
connection diagram
Technical data
Block
diagram
Direct drive system EDS 920
Wiring
diagram
General
Fascia
Motor and drive
Replacing motor electronic system
Replacing motor mechanical system
Pitch
control
Stroboscope
Tonearm and
tonearm suspension
Fitting a 1/2" cartridge
Removal of tonearm from bearing frame
Removal of
complete
tonearm
Replacement of spring housing
Adjustment of tonearm suspension
Anti-skating
control
Tonearm cue
control
Adjustment point
Replacement of
cue control plate
Tonearm
control
Continuous play
Starting
Manual
start
Muting
Shut-off
End of play
shut-off
Adjustment
points
Power
fuse
Tonearm set down point
Shut-off point
Tonearm lift off height
Pull
magnet "start/stop"
Pull magnet "cueing"
Tonearm does
not set down
Vertical tonearm
movement is inhibited
Platter does not rotate
Tonearm does not set down on
edge
Motor
does not
shut-off
Spare parts list with exploded views
Lubrication
instructions
AC 50 or 60 Hz
110 — 125 V and 220 — 240 V
Quartz stabilized electronic direct drive system Dual EDS
920, PLL control
Approx.
4 W,
motor
during play
< 50 mW
(until
nominal speed is
reached) approx.
1.8s
at
33 rpm
Non-magnetic dynamically
balanced, complete rotary mass detachable approx. 1.5 kg
33 and 45
rpm, electronically
switchable,
quartz
stabilized
In PLL technology, quartz
accurate for both speeds, separately adjustable,
range of
adjustment ± 5.5 %
Quartz accurate, illuminated stroboscope with
automatic frequency switch-over
for
33 and 45 rpm
20 graduations per minute
DIN
<
±0.025 %
WRMS < ±0.015 %
Rumble unweighted signal-to-noise ratio >
52 dB
Rumble weighted signal-to-noise ratio > 75 dB
Torsion-resistant
"ultra-low-mass" aluminum
tonearm, in gimbal
4-point
suspension, tonearm balance
weight with tuning anti-resonator
221 mm
26° 4'
0.16° /cm
Vertical < 0.07 mN (0.007
g)
Horizontal
<
0.15
mN
(0.015 g)
From 0 —
20 mN (0
-2
g) infinitely
variable with 1
mN
(0.1 g)
Calibration in range
from 2—
15 mN 10.2 -
1.5 g)
Detachable, suitable for
ultra-low-mass
cartridges, with long carrier
plate laccessory) ,
also suitable for
cartridges with Dual shap-in
mounting and for
cartridges with 1/2"
mounting
and a weight of 2 to 9
g (including
mounting hardware)
Adjustable overhang:
5
mm
See separate data sheet
Approx. 8 kg
3

BLOCKSCHALTBILD
BLOCK DIAGRAM
SCHEMA
SYNOPTIQUE
Motor
Motor
Moteur
Frequenz -Generator
Frequency
generator
Gänärateur
de fräquence
Motor -Treiber
Motor Driver
Moteur Driver
Quarz-Oszillator
Quarz-oscillator
Oszillateur Quartz
Amplituden
-Verstärker
Amplitude Amplifier
Amplificateur
d'Amplitude
Sample-and Hold
-Schaltung
Sample-and-hold circuit
Circuit de
contröle avec
mise en memoire
Tonhöhen
-Regler
Pitch Control
Räglage finde la vitesse
Teiler 1 : 81
Divider 1 : 81
Diviseur
1 : 81
Schmitt-Trigger
Schmitt Trigger
Schmitt
Trigger
Drehzahlumschalter
Speed changeover
Commutateur de
vitesse
Teiler 1 : 60
Divider 1 : 60
Diviseur 1 : 60
1
Teiler 1 : 512
Divider
1 :
512
Diviseur 1 : 512
Digital
-Analog -Wandler
Digital
-Analog converter
Convertisseur
digital-analogique
Amplituden
-Begrenzer
Amplitude
Limiter
Limiteur d'Amplitude
Teiler 1 :
512
Divider
1 : 512
Diviseur
1 : 512
PLL-Schaltung
PLL-Ci cuit
Circuit-PLL
0
Tonhöhenschalter
Pitch switch
Commutateur
räglage de la vitesse V
Impuls -Former
Pulse shaper
Modulateur
d'impulsion
Impuls -Decoder
Pulse Decoder
Däcodeur ä
impulsion
Konstant
-Stromquelle
LED-Stroboskob
Constant Cur ent Source
- 1111 0.- LED-Strobe
Source de
courant constante Stroboscope ä LED
Transformator
Transformer
Transformateur
Drehzahl -Drift -Erkennung
Speed deviation
Identification
lndiquateur
variation de vitesse
Plus -Minus -Erkennung
Plus -Minus Identification
Identification Plus -Minus
Plus -Minus Anzeige
Plus -Minus indication
lndication Plus -Minus
Gleichrichter
Rectifier
Redresseur
Spannungs-Konstanthalter
Voltage
Stablizer
Rägulateur
de tension
Digital
-Analog -Umformer
Digital-Analog-Converter
Convertisseur
digital/analogique
Kaskadenschalter
Cascade switch
Contacteur ä plots
13-Digit-Ska a
13-Digit Scale
Indicateur ä
13 positions

EDS 920 direct drive
system
The newly developed direct
drive system of the CS 731 Q
turn-
table is a
successful synthesis of our
well-known motor principle
and a highly sensitive electronic system
which receives its accu-
racy from a quartz crystal. The
drive motor is a DC motor with
no commutator in which
commutation is carried out by two Hall
generators which detect the position of the rotor equipped with
an 8 -pole ring magnet and which also
actuate the corresponding
windings of the rigid flat coils. The
synchronously rotating mag-
netic return circuit plate and the ring magnet enclose with a small
air gap the
non-ferrous coil arrangement so that, on the one
hand, the
drive system displays
an extremely
uniform running
characteristic without pole sensitivity and which displays, on the
other hand, a high torque in spite of the economical energy
supply. After the nominal speed has been attained, the energy
supply required for maintenance of rotation is
less than 50 mW.
F ig. 3
Description of function
At a motor speed of 33 1/3 rpm, the 200 -pole frequency genera-
tor rigidly coupled to the motor delivers a frequency of 111 Hz
which
is amplified in the input amplifier and prepared in the cam
form. This
Signal
is applied as an actual value to the PLL circuit.
An oscillation
frequency of 4.608 MHz,
which is control led by a
highly precise quartz crystal, is generated in the quartz oscillator.
The actual reference
frequency — that is to say, the set value — is
derived from the oscillator frequency by a multi-stage divider.
In the PLL circuit, the
actual value and set value are compared
with one another as regards amount and phase. In the
case of the
slightest deviation, a control pulse is applied to the digital/analog
converter which obtains from this an analog
control signal which
is converted
into a current alteration in the subsequently connec-
ted motor
control circuit. In the drive motor, this current altera-
tion causes spontaneous stabilization of the minimal speed
devia-
tion.

The
set value
necessary for
the 45
rpm
speed is
generated
in the
voltage
divider by
alteration of
the
divider
ratio. For
pitch
control,
a
continuously
variable
control
signal ,
with
which the
control
loop
is fed, is
obtained by
means of
a
complicated
division
pro-
cess.
Thus the complete control
range, like the nominal speeds, is
coupled in a
locked-phase relation to the
quartz oscillator. The
speed
accuracy in the pitch range is
practically the same as in the
case
of nominal speed. The speed
deviation preselected with both
pitch controls is maintained even if the
pitch switch is operated
or if the unit is seitched off.
In the speed logic, the display unit of the
CS 731 0
obtains from
the actual speed the basic
information as to whether the
actual
speed
of the nominal speed is
faster or slower. A further
logic sy-
stem activates the plus or
minus sign of the display unit.
Both
signals are dark at rated speed.
From the digital
information on the actual speed, a further
digital/analog
converter
receives
relative and
analog information
which is transformed
in the cascade switch to
an activation voltage
for the 13
digital displays. In the
display itself the information is
still completely analog as the
individual digits are activated with
differentiated voltages
and light up accordingly.
This display
is as accurate as it is
practical. The power
section
supplies the various partial
circuits with carefully
filtered and
stable operating voltages.
General
The listed item numbers refer to the
following spare parts lists
and exploded
views.
The cover can be easily withdrawn from the
hinged splice pieces.
To remove the turntable,
remove both fillister head screws
(98)
and the discs (86) with which the mounting plate (197) isscrewed
down. The turntable can be I
ifted out of the bracket (12) after
disengaging the
three transport locking screws.
Now detach the
following plug
connections:
1) Both
single -pole plugs (122)
on power switch
(106).
2) The 4
-pole
plug
(160) on the solenoid protective circuit
(185).
31
The 5 -pole female
multi-point connector (158) at the display
unit
(35).
4)
The 5 -pole female
multi-point connector (185) at the distri-
butor board
(24).
Fascia
To dismantle the fascia, remove
both attachment screws (21)
with which the display
unit is mounted on the bracket
base.
bracket base.
The top
of the
plate
(17)
is
attached with 3
fillister head screws
(98) and three washers (86) and
the
bottom is
attached
with
three
cheesehead screws
(501.
Fig. 4
Motor and drive
Special tools and measuring instruments are necessary for repair
of the Dual EDS 920. Therefore, work on the motor or the
motor
electronic system should only be carried out by an authorized
Dual service station.
Replacement of the motor
electronic system, complete
The
individual modules (151/152/153) are
plugged into the
main
board.
In addition, they are held by
means of supports
(154).
Moreover, module 1 is also secured with the fixing screw (159).
When replacing
the complete motor
electronic system,
proceed
as follows:
1) Remove the fillister head screws (97) and the
four
supports
(154).
2) Remove
fixing screw (159) (module 1).
3) Detach the plug connections fo the connection cable — refer
to wiring
diagram Fig. 3.
4) Detach the motor electronic system
completely from the
mechanical system of the motor and replace it.
Replacement of
the mechanical system of the
motor
1) Release both threaded pins (19)
and withdraw plate cone (22).
2) Remove the complete motor electronic
system — see above.
The plug connections of
the connecting cable need not be
removed.
3) Remove both fillister head screws (99)
and the cog
(105).
4) Withdraw the mechanical system of
the motor and replace it.
Fig. 5
Pitch control
With the pitch control, each of the two rated speeds, 33 1/3 and
45
rpm, can be varied by ± 5.5 %. With the seesaw switch (16) at
"ON" position, each nominal speed can be altered by means of a
separate
potentiometer (14). At the same time, the
optoelectronic
display
scale
(35)
indicates
the percentage
deviation from the
nominal speed.
I ndependently of the potentiometer setting (14), the speed cor-
responds with quartz precision to the respectively switched no-
minal
speed, if the seesaw switch (16) is
in ''OF F"
Position.
Stroboscope
The stroboscope markings
on the turntable edge are
flashed from
the diode plate (148) by means of quartz accurate frequency.
The display is independent of power frequency and does not re-
quire additional stroboscope markings for different speeds and
line
frequencies.
6

04.
4
When the
stroboscope markings seem to be
stationary both no-
minal speeds (33 1/3 and 45 rpm) are
accurately adjusted. If the
markings
seem to run ahead the speed is higher. If
the markings
seem to run back the speed is lower
than the nominal speed.
By means of the speed of the apparently
"wandering" markings
the
speed selected with potentiometer (14) can be determined at
high speeds: 1 graduation/sec. = 0.9 % deviation. After releasing
the
fixing screw (159) and removing both fill ister head cap screws
(96) the
stroboscope housing can be removed
(149). After re-
moving the retainer piece (147) the three LED's (148) can be re-
placed.
Tonearm and tonearm suspension
The light,
torsion-resistant all-metal tonearm is twingimbal
mounted. Suspension is by means of four hardened and precision
polished steel points which rest in precision ball bearings. The
tonearm bearing friction is thus reduced to a minimum.
Bearing
friction vertical 0.07 mN (0.007 g)
Bearing friction horizontal
0.15 mN 10.015 g)
as
related to stylus point.
This ensures extremely
favorable pick -up conditions.
Before
setting
the tracking force corresponding to the
built-in pick -up
cartridge the tonearm is balanced at 0
position of the tracking
force scale. Coarse adjustment is
carried out by moving the
weight with
stem
(60)
subsequent fine
adjustment by turning
the front knurled ring on the weight.
The balance weight is designed so
that pick -up cartridges having
a dead weight (including fitting material) of 2 — 9
g can be
balanced.
The tracking force is produced
by
tensioning the
coil
spring fitted
in the spring
housing (74). The rotary knob
(69) is
provided with a scale which permits accurate adjustment
of the
tracking force in the range from 0 — 20 mN (0 - 2 p) by means
of the
merk ing dots.
Fitting a 1/2" cartridge
The
description of retrofitment
for fitting a 1/2"
cartridge (re-
placement of
carrier plate etc.)
should be taken from the
opera-
ting instructions.
milm>"dal!iii11111111111111
Fig. 6
83
11
Removal of tonearm from bearing frame
1) Secure unit in repair jig. Remove weight (60). Unscrew ten-
sioning screw
(52). Set rotary knob
(63) to 0.
21 Turn
unit
upside
down. Remove
hexagon
nut (34) and screening
plate (119). Unsolder tonearm
leads on
muting switch
(120).
31
Unscrew tensioning screw
(70).
Remove rotary knob
(691,
disc (68) and indicator
(67).
4)
Loosen locking nut
(61) and
unscrew threaded
pin
(65).
51 Remove
tonearm 130) with bearing
(71).
Assembly
takes place in reverse order.
Removal of tonearm assembly with tonearm bearing
Proceed as follows:
1. Secure unit in
repair jig. Set rotary knob
(69) to
0. Lock
tonearm (30). Remove
weight
1601.
2.
Turn
unit upside down.
Remove
hexagon
nut and
screening
plate
(119).
Unsolder
tonearm leads on
muting switch
(120).
3. Remove retainer disc 1911. Remove main lever (167) and
bearing block (166). Remove securing disc (89). Lift off ad-
justing bar (168) and rotary bearing (170) and swivel to motor.
1
141 187
96
168
190
167 176 97

4. Disengage tension
spring
(136).
Release
securing
disc
(90)
and remove
skating lever (134).
5.
Remove hexagon nuts
(94). Remove
countersunk screw
(138).
Remove
counterbearing (135) and
segment (124).
6. Retain
tonearm (30) and
frame (63). Remove
filister head cap
screw
(88). Remove
tonearm complete
with
tonearm
bearing.
When fitting the tonearm
proceed in reverse order but ensure
that the threaded pin
(62) seats correctly on
ball bearing.
Replacing spring housing
Remove
tonearm
(30) from
bearing
frame (66)
as
described
above.
When installing notice that the helical spring
engages in the cut-
outs
of the bearing (71). Mount
tonearm
(30)
again. Set
bearing
play as
described below using threaded
pin
(65)
a'nd lock nut
(61).
Adjusting
the tonearm bearing
First balance tonearm accurately. Both
bearings must have slight,
just perceptable play. The horizontal tonearm bearing
iscorrectly
adjusted when at anti-skating setting 0.5 and being touched it
slides in without resistance. The vertical
tonearm bearing is cor-
rectly adjusted when it swings in after being touched. The play
of the horizontal tonearm bearing should be
adjusted with thre-
aded pin
(62), the play of the vertical
tonearm
bearing with
threaded pin
(65).
A nti-skat ing device
Adjustment of anti-skating force is
carried out by means of
turning the knurled ring on the cover. According to adjustment
the
asymmetrical cam disc guides the
skating
lever (134) from
the tonearm pivot
point. The anti-skating
force is
transmitted to
the
segment
(124) by means of tension spring
(136) and to the
tonearm.
Optimum adjustment is carried out
at the works for styl i with a
tip radius of 15 /im
(conical),
5/6 x 18/22 pm
(elliptical) 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 Dual
service station.
Cue control
By moving lever
(187) forward (
V)
lift cam
(188) rotates. The
slide bar (168) connected to it
transmits this
movement to the
lift pin wh ich
then
raises
the
tonearm. As a
result the
cue
control
permits set down and
lift
off of the
tonearm
at any
desired point
outside the shut-off range.
The slide
bar (168) is released again by
moving the
cue
control
lever (187) to the rear
(1).
As a resu lt of the action of
compres-
sion
spring the lift pin is returned to
neutral Position and thus
lowers the tonearm.
Lowering of the tonearm is damped by
silicone oil in the lift tube.
The set down speed can be
varied by adjusting the pretension
of
compression spring (lift plate 176).
Accord ing to
Operation of
the adjusting ring
(82) in
position "4" the
lowering speed is
slower, in Position
"441" it is faster.
Adjustment
point
The lift
height can be
varied by
turning adjusting
screw
(51). The
distance
between
record and
stylus should be
approximately 5 mm.
Fig. 8
63
66
65
61
71
81
88
124
94
n
emeee...2 _
r
•
'
,
• I
61
62
74
69
70
82
83
138
Replacement of cue
control plate
Replace cue
control plate as follows:
1.
Fix unit on
repair jig and
lock tonearm.
Turn unit upside
down.
2. Remove securing disc (89). Detach
main lever
(167) and
bearing block
(166).
3. Remove securing
disc (89).
Rernove
adjusting
bar (168)
and
rotary bearing (170)
and swivel to motor.
4. Remove both fil ister head cap screws
(971, remove
cue
control
plate complete (176).
Fitment takes place in
reverse order. lt should,
however, be noted
that the pressure piece in
the cue control plate
(176) engages
correctly in adjusting
ring (82) (varying the
lowering speed.
Fig. 9
To
nearm
control
Automatic movement of
the tonearm is indicated by the control
cams on
the inside of the
cam
wheel (16)
on rotating through
360 0 .
The
control elements for raising and
lowering are the control
lever
(167) and the lift pin, for
horizontal movement of the
tonearm control
lever
(167) with
segment
(124).
8

4
The automatic set down point is designed for 30 cm and 17 cm
records and is coupled to the platter speed
changeover. Set down
points of the
tonearm are determined by means of stop of spring
bolt of
segment (124)
at the adjusting bar
(168).
Limitation of
the horizontal
movement of the tonearm is produced by stop of
segment on adjusting bar (168) which is I ifted off only during set
down by the
main lever (167) and reaches the
swivel
range of the
spring bolt on the segment.
On completion of set down (lowe-
ring of
the tonearm onto the
record) slide
bar (168) is
released
again and returns to its neutral
position. As a
result,
this is out-
side
the range of the spring bolt so
that unimpeded horizontal
movement of the
tonearm is possible
for playing.
Continuous automatic play
The continuous automatic play is
operated by
turning
knob
(84)
to "00". Switch bracket (179) is actuated by knob (84). Switch
rod
(180) keeps change
lever
(165) in
start position.
After playing the record the tonearm returns automatically
to
the lead in groove of the record. This process will be repeated
until knob (84) is in position "1".
Adjustment point
Withdraw power plug.
Remove turntable
(3).
Bring knob (84) to
position "oo". Turn cam
wheel to center
position. The change-
over
lever deflects the cam follower lever
(U). By
this means the
cam
follower lever tip
must be brought at
least to the cam track
center. Adjustment by bending the
switch rod (189).
Starting
Operation of push-button (59)
"start"
results in the
following
functions:
a) The
right hand pull magnet
(142) operates cam
followerlever
(165). At
the
same time the power
switch (106)
is operated
by the
contact arm (127) coupled to
the switching arm (78)
and the
motor and turntable start to
rotate.
b) This
Operation also releases start slide (39)
which is drawn in
the
direction of the cam wheel by
means of the tension
spring
(38).
By this means the
shut-off
lever
(8) on
the cam
wheel
(25) is brought into the
range of
the follower (M)
(plate cone
22) and the cam
wheel driven by this means.
Manual
start
The
detent (126) coupled to control arm
(78) engages in the
square
plate (125) when the tonearm is
moved inward by hand
and retains the tonearm in this position.
The power switch is
operated by the control arm and thus the motor and platter
start to rotate. After reaching the run-out groove of the played
record return of the tonearm and shut-off of the unit take place
automatically. lf, on the
other hand the
tonearm is lifted off
the
record before playing is completed and moved onto the rest by
hand, the pin of
segment (124) disengages the detent
(126) so
that the control arm is returned to its starting
position. As a
result, the power switch shuts off the power supply.
M uting
switch
To
prevent
disturbing noises
during
automatic Operation
of the
tonearm
the unit is
fitted with a
muting switch.
Control of the
switch
springs for both
channels is
effected by the cam
wheel.
With the
unit in neutral
state the
short-circuit of the
pick -up
leads is
eliminated.
Adjustment point
In neutral
position of the cam
wheel a contact
distance of ap-
proximately 0.5 mm
should be
present between
contact springs
(F)
and
short-circuit strips (L). If
necessary
bend short-circuit
strips.
Spray contact springs with
suitable
means.
Fig. 10
Fig.
11
Fig.
12
Stopping
When push-button (59)
"stop" is operated the
changeover lever
(165) is
brought into stop position by
means of the left hand
pull magnets
(142). As a result the start
slide is released which is
drawn in the
direction of the
cam wheel by means
of tension
spring (38). By this
means the shut-off lever is
brought into the
range of the follower
on the platter
pinion (PR) and the cam
wheel
(25) is thus
driven.
9

Shut-off Operation
The
functions of end switch-off and stop
switch ing are determi-
ned by the position of the deflection
lever (U).
The
deflection
lever
(U) is brought to stop
position by the main lever
(167) after
every
start Operation (longer end of
deflection lever to cam wheel
center).
After playing of a record shut-off is
initiated by the follower (M)
of the
platter (3) and the shut-off
lever (A).
The
shut-off bar
(128) is only moved
synchronously by the bolts
of the
segment (126) in the shut-off
range.
In
the shut-off range
Irecords 116 to 122 mm 1;b1 the
shut-off
lever (A) is guided onto the
follower (Fig. 13
a) by the shut-off
bar (128). The follower (M) engages shut-off lever (A). By this
means cam wheel
(25) is brought out of zero
position in engage-
ment with pinion of
platter (Fig. 13 b). The main lever
(167)
guides the tonearm back and effects tonearm lowering onto the
support.
During
run-in of the cam wheel
into zero
position the
roller
(76)
of the switching
arm (78) run-in to the cut-out
provided on the
cam wheel
and operate the power switch
(106).
Adjustment
points
Power fuse
After
removing both
fastening
screws
and
detaching
power secti-
on
cover the fuse (102)
on the
power
plate
(101)
can
be replaced.
Tonearm set down point
The set down
point of the
tonearm can be
altered with
the ec-
centric bolt (172).
If the stylus
sets down too
far in or out
on
the record turn the eccentric bolt
(172)
correspondingly
right or
left.
Shut-off point
The
shut-off
point (shut-off range
records 116
— 122
mm 95) can
be altered with the eccentric (E) on the segment (124).
Tonearm lift-off height
The tonearm lift-off
height (during
automatic operation) can
be
altered with adjusting
sleeve (177). Withdraw
power plug. Un-
lock tonearm. Rotate cam wheel (25)
out
of
zero position until
tonearm has reached its highest point.
The
tonearm should be approximately 5 mm
above the tonearm
support stop
(Fig.
16). If
necessary, Turn
adjusting sleeve (177)
to left or right.
Fig. 13
22
A
25
128
b.)
Fig.
14
Fig. 15
Fig.
16
10