Panasonic Technics SL-1800

Features
Turntable section
The newly developed double-insulate vibration-damping unit,
Unique
in
Technics,
was
developed
through
high
mass
design
placing particular emphasis on acoustic quality, (See Fig.24).
The turntable platter and the tonearm are installed on the base
land solidly girded through the integral construction of the main
base and the bottom of the case, while the entire base is
floating in stable equilibrium with respect to the main turntable
base through insulators. composed of metallic springs and a
viscoelastic materi
The main turntable base is also provided with an insulator
‘superior in vibration damping characteristics for protection trom
undesirable external vibrations. As a result, a combined effect
is obtained through the use of two insulators to maintain
‘excellent absorption and cutoff of external vibrations and local
resonance from speaker output thus effecting remarkably
improved feedback prevention.
Motor construction peculiar to Technics in which the rotor of
the motor is integrally connected to the turntable platter.
(See Fig. 24).
In
Technics
turntable
systems
we
took
the
lead
in
the
world
by
putting the Direct Orive system on the market with a marked
improvement in the pertormance ot turntables. Since then,
we have developed numerous turntaples of high performance,
furnishing new topics of conversation each time.
(One of these achievements is the motor construction of this unit,
‘nique and singular ip the world, in which the rotor of the motor
is directly connected to the turntable platter.
Moreover, the motor base has been integrally connected to the
turntable base of diecast aluminum for presenting turntable
‘systems of higher accuracy and rational construction
MDependable one chip IC. (See Fig. 25).
First in development of the IC (AN630) of the Back Electro-
motive Force Frequency Generator system. The motor drive unit
control unit and various additional functions are integrated into
Turntable base is of diecast aluminum for slim and compact
the B.FG" system which utilize the Back Electromotive Force
Frequency Generated in the drive winding of the Direct Drive motor.
Consequently, superior temperature, drift and transient chars
teristics are obtained improving the overall reliability of the
turntable system,
The
one
chip
IC
(AN630)
employed
in
this
unit
has
a
total
of
321
‘elements
such
as
transistors,
diodes,
resistors
and
capacitors
consolidated
in a silicon
substrate
approximately
3 x2.7 mm?
in
size.
We take pride
in the fact that
the one chip IC (AN630)
represents
the world’s
largest
degree
of integration
as a bipolar
linear
IC.
*
Back
Electromotive
Force
Frequency
Ger
ator.
‘One
chip
IC
(AN
630)
Interior
of
AN
630,
I HiAidelity pertormance with rumble (signal to noise ratio) of
73 dB (DIN4SS39B), wow and flutter of 0.025% (W.R.M.S.).
‘The ultra-low speed brushless DC motor employed in this unit
thas the extremely low power consumption of about 0.1 W, and ie
thus free trom vibrations due to excessive energy or heat
‘generation.
Tho
high
performance
of
the
Direct
Drive
motor
is
due to the etticiency of the newly developed double insulator and
to the utilization of the one chip IC of the B.FG system
lm Prism type strobe illuminator also serves as pilot lamp.
Cro:
Motor shalt (Centre spin
)
section of motor portion and double insulator
Position detecting rotor
Stator
Position detecting coil
Tonearm
Turntable m: Stator coil ]
——_|
Rotor magnet | |
Dust cover
pest
ul
pessiats
me
aes
tee
|
Feit
2nd insulator
Visco-elastic material
Stator frame