Dual 1237 A - Unpacking and Installation; Start and Operation; Balancing the Tonearm

Unpacking and installation
Please also note if your 1237 A is part of a compact unit or a console
follow the instructions of the latter manufacturer.
Remove all transport protection information sheets and the
packing material from the turntable. Please read all notes before
removal.
Loosen the transit safety screws (Fig. 1) by turning them clock-
wise until they slide downward (about 15 mm) releasing the
chassis from the base and continue turning them clockwise to
tighten the screws into the top of the chassis. The turntable is
now My spring-supported position required for play position
(Fig. B
Take the tonearm counterbalance out of its Styrofoam insert.
Loosen the set screw (2) at the rear of the tonearm, then insert
the shaft of the counter balance in the opening provided for
this purpose. The triangular shaped notch of the shaft must
point in downward direction (Fig. 2). Pages 12 and 13 explain
how to balance the tonearm and then apply oA pressure
and anti-skating.
The separate Technical Data sheet advises you on setting tracking
pressure for the cartridge already inserted in the unit.
Later transport
Be sure the tonearm is locked and the sty!us guard flipped down.
Also, release the transport safety screws them counterclock-
wise, then pull them up and tighten again by continuing to turn
so as to secure the chassis against the base. The tonearm coun-
terweight should be removed. |
should shipping of your Dual unit become necessary, make sure
that the packing is adequate. Use, if possible, the original packing
material in which you received your unit.
Attention: After each transport or installation, the unit must
be started once with the tonearm in locked position for auto-
matic adjustment of the shut-off mechanism. To initiate the
automatic ‘‘Start”’ or Stop” function, press the start switch all
the way in each direction. :
Start and operation
Single play operation
Insert the short, single-play spindle (13) and, for 45 rom re-
cords, the centerhole adapter (17), then place the desired record
on the platter.
select the platter speed 33 1/3 or 45 rpm, release the tonearm
and raise the stylus guard.
1. Automatic start.
Indexing is interlocked with the speed selector, so the tonearm
will set down into the lead-in groove of 12”’ (80 cm) records
when switched to 33 1/3 rpm, and into the lead-in groove of a
7” (17 cm) record when set to 45 rom. To initiate ‘’start’’ func-
tion, press the switch (8) all the way. The switch returns to its
neutral position immediately after its release. The tonearm
moves to the record, lowers slowly and sets the stylus gently in
the lead-in groove of the record.
2. Manual start |
a) Move cue control lever (6) to position ©.
b) Move tonearm by hand over the desired point on the record.
c) Tap control lever to position »
Attention!
With the cue control lever in position ¥ and automatic start,
the tonearm moves to the setdown position. By tapping the
control lever the tonearm will descend to the record.
12:
The height of the stylus tip over the record in the raised tone-
arm position ¥ can be varied about approx. 6 mm by turning
the adjustment screw (5).
3. lf a record is to be played repeatedly or played once more
from the start
Move switch to ,,start’’.
4. Interruption of play
Move cue control lever to position ¥..
After repositioning the tonearm, and after operating the con-
trol lever reproduction is started again with the last few reals
which were played.
5. Shut-off
Move switch to position ,,stop”’.
The tonearm will return to its rest position and the unit will
shut off automatically. :
Note: Records with a different diameter, such as older 25 cm
records, are played as described in ‘’2. Manual start’.
After the record has been played, shut-off and tonearm return
is automatic irrespective of having started the unit manually or
automatically. The tonearm should then be locked and the sty-
lus tip protector moved down again.
Automatic record change
(For 30 cm records/33 1/3 U/min or 17 cm records/45 U/min
only).
Insert the changing spindle (18) or the automatic changer
spindle (16)* so that pin fits into the slot in the shaft.
secure the spindle or automatic changer spindle in place by
pressing down on it and turning it to the right until it stops.
load up to six records of either 17 cm 45 rpm or 30 cm
33 1/3 rpm, on the spindle or automatic changing spindle.
Move the operating switch to ,,start’’. This will cause the first
record to drop and the tonearm to be set down in the lead-in
groove. Should you want to interrupt any record and cause the
next to drop, move the operating switch to ,,start’’.
Note: Records already played can be lifted back onto the spindle
platform for replay or FoMOVER entirely. The spindle need not
be removed.
*
The
special
automatic
changer
spindle
AS
12
for
17
cm
re-
cords
with
a
large
center
hole
is
available
from
your
spe-
cialist
dealer
as
an
accessory.
Balancing the tonearm
Precise tonearm balance ts most important for cartridges with
low stylus pressure. Balancing need be done only once. We re-
commend, however, that you occasionally inspect the tone-
arm.
The pickup arm is correctly balanced If it remains in a horizon-
tal position when released, i.e. if it does not rest against the
lower or upper end stops and If it returns to a horizontal posi-
tion if defleated vertically by a small distance.
Shifting the counterbalance (1) on its shaft balances the tone-
arm coarsely; turning the counterbalance weight balances the
tonearm exactly.
1. With the pick-up arm still locked on the arm support, turn
the turntable a few revolutions in a clockwise direction by
hand.
2. Set the tracking force (3) and anti- -skating (4) controls to
“QO”, unlock the tonearm, and Jift it from the tonearm rest.
3. If the tonearm does not come to rest horizontally, loosen
setscrew (2) and slide the counterbalance with its shaft
until an approximate balance is has been achieved.