|65,000yen(around the 1980 time)
It is MC type cartridge which adopted the amorphous boron pipe.
new-materials amorphous boron pipe with a wall thickness of 0.025mm is adopted
as a boom.
the ratio which was excellent though the boron was light -- while
having rigidity (Young's modulus/density), it has the physical properties of the
fusing point of 2,300 degrees C, and has become the element optimal as a
material of a boom. And since an amorphous boron is in the amorphous state with
which small particles were tightly got blocked, compared with the crystal boron
which is a collection of big crystals, destructive intensity is large also about
three to 4 times.
In order to use this material in the optimal state, while
succeeding in the ultra-thin pipe formation by the original C.V.D. (Chemical
Vapor Deposition: vapor phase epitaxy) method, it is realized [ of the boron
emulsion side / equalization and ] whether it is precise.
By this, the weight saving of the effective mass of a vibration system
is carried out to 0.168mg, the mechanical impedance in upper register is
held down to the minimum, and faithful and exact trace is enabled with
light needle pressure.
diagram special ellipse needle is adopted as a needle, and 0.01mg or less is
The taper cut of the point of the boron pipe which fixes a needle
is carried out, and it is correctly attached to the precise rectangle hole by
laser beam processing.
The power generation coil maintained the optimal
mass balance while making the whole vibration system light using the cross type
volume frame of hard resin, and it has eliminated the slump of the
characteristic by division vibration. This volume frame system has a merit which
it is possible to wind a coil around a vibration-system axis symmetrically, and
can arrange many characteristics of a right-and-left channel.
to obtain a small and powerful magnetic field, a rare earth cobalt magnet and a
rational yoke structure are adopted as an internal structure. Moreover, a
vibration system is supporting with the one-point type of mounting which has a
track record in DL-303 and DL-103 series, can always hold a coil correctly in
the center of a magnetic field, and is suppressing distorted generating by a
power generation system low.
||MC type cartridge
||0.2mV (1kHz is horizontal 5 cm/s)
|Play frequency range
||20Hz - 75kHz
|Output load impedance
||40ohms (20Hz - 20kHz)
||100ohms or more (about [ transformer ] 40
||28dB or more (1kHz)
||Less than (1kHz) 1dB
||35x10 to 6 cm/dyne
||14x10 to 6 cm/dyne (100Hz, record
|Needle point (chip)
||0.05x0.1mm angle solid diagram special
|Proper needle pressure
||Main part exchange (\39,000)