Dual 1226 - Anti-Skating Device

Anti-Skating Device
The geommetrically caused skating force ac—
ting on any tonearm is eliminated to a lar-
ge extent in the case of the Dual 1226 by
means of a precision antiskating device.
The skating force is dependent on the tone
arm geometry, on the stylus force and the tip
radius of the cartridge stylus. The inward
pull of the tonearm caused by the skating
effect leads not only to undesirable jumping
of the tonearm when set down on the record
but also unequal forces on the two opposite
groove walls with resultant unfavourable ef—
fects. These can be corrected with the aid
of a suitable anti-skating device. By tur-
ning the knob (70) of the anti-skating de-
vice located on the cover the asymmetrical
plate cam (230) is moved. This plate cam
has two different curvatures which, accor-—
ding to the different scales used, for sphe-
tical and elliptical tip styli and for CD 4
pick up cartridges, move the skating lever
(234) out of its position of rest and trans-
mit the counter force to the tonearm by
means of the tension spring (242). Skating
adjustment is set at the works for conical
styli with a tip radius of 15 + 2 pm and
for elliptical styli with measurements of
5/6 and 18/22 wm and also for CD 4 cartrid-
ges. The hexagon nut (231) is firmly tighte-
ned and locked with paint. Readjustment
should only be attempted with the aid of the
Dual Skate-O-Meter and the L 096 test record.
This is best done by authorised Dual service
station.
Trouble Cause
Stylus skips a) Tonearm not balanced
b) Stylus force too low
c) Stylus worn or chip-
ped
d) Excenssive friction
in tonearm bearing
e) Ball (201) missing
from shut-off rail
f) Anti-skating wrongly
adjusted
Fig. 9
a) Anti-skating force O-set-
b
Anti-skating force
—— V-spring
ting. No compensation
of the skating force ta-
kes place as a result of
the action of the tension
spring at the fulcrum of
the tonearm.
=
Anti-skating mechanism
set to 1.5” on the scale
for elliptical styli, Tone-
arm on tonearm rest.
The tension spring pro-
duces the anti-skating
force which is transmit-
ted to the tonearm via
the segment. The V-spring
presses the skating lever
against the plate cam,
As "'b"’ but tonearm abo-
ve platter.
Remedy
a) Balance tonearm according to operating
b)
c)
d)
e)
f)
instructions
Set stylus force to cartridge manufactu-
rer's recommended value
Replace stylus
Check tonearm horizontal pivot. Should
have barely noticeable play. Adjust verti-
cal bearing only with the left bearing
screw pat and the horizontal bearing
screu (244). Horizontalbearing is correctly
adjusted when the tonearm, with anti-skating
0.5 p, swings freely from center to rest.
Replace ball (201).
Correct antiskating setting