Audio Database

The

Lo-D HT-660
67,000yen(around the 1979 time)

Description
 
The Quartz nowait lock and the full auto player system which carries an electronic return.

The uni-torque motor by a technology original with a Lo-D is carried in the motor.
A uni-torque motor is a motor which asked for perfect circular motion from the principle,A rotor magnet of a doughnut form by which the magnetizing was carried out, and 2 sets of star-shaped flat coils shifted 22^5 degrees are consisted of by eight poles, and the amount of torque generated from these two coils and magnets becomes fixed very always about which moment. This principle can be expressed with the easy numeric expression "sin2theta+cos2theta=1." In the uni-torque motor, further, the simple structure of a brushless and a slotless & coreless is adopted, and the endurance is also improving sharply.
In HT-660, the crystal control (Quartz nowait-lock PLL servo) hardly influenced by the voltage fluctuation, or temporality and a temperature change was poured on this uni-torque motor, and the high-precision rotation is realized.
Moreover, a startup property reaches a constant-speed in 1/2 rotation.

The electronic braking system which can perform a record switching and a velocity switching quickly is built in. This is shortening this stop time for about 25 seconds in no equipping DD till about 3 seconds.

By adoption of 2 motor system which became independent about the motor for a turntable rotation, and the motor for an arm drive, a cross interferencee is lost, and it considers so that a basic performance may not be spoiled.

The photoelectron type Ohtori turn detection organization is carried.
Unlike the conventional mechanical return detection scheme, a return is possible by no contacting in the combination of the light source (light emitting diode), a shutter, and a photosensor (Cds).

It is possible to carry the arm height adjustment mechanism, to adjust the degree of level of an arm correctly, and to rectify a vertical tracking angle error.

A thing 330mm in diameter is adopted as a turntable.

The front operation soft push switch which can perform an easy operation with a book jacket closed is adopted.

Uni-torque The

Rating of a mode
Form Quartz nowait-lock DD full auto player system
<Phone motor part>
Drive system Quartz nowait-lock DD full auto
Motor Flat form non-commutator DC servo motor (uni-torque motor)
Turntable 330mmphi aluminum die casting
Constant-speed speed 33 1 / 3 or 45rpm
Wow and flutter 0.025%(WRMS)
SN ratio 75dB(DIN-B)
Load characteristics 0%
Rotational frequency deflection Less than 0.003%
<Tone arm part>
Tone arm Stylus-force Direct-reading type static balance type pipe arm
Arm effective length 220mm
Overhang 15mm
Tracking error 2 degrees
Stylus-force adjustable range 0-3g / 1 rotation (being a 0.1g step Direct reading)
Application cartridge weight 4g-10g
Arm height adjustable range 3mm
<Cartridge part>
Cartridge VM form (VFS-261)
Frequency characteristic 20Hz - 20kHz
Output voltage 3mV (1kHz, 50 mm/s)
Channel balance 1dB
Stylus force 2g
The needle used 0.7mil diamond stylus (DS-ST26)
<Cabinet part>
Cabinet The product made from aluminum die casting
Insulator Air suspension
<Synthesis>
Supply voltage AC100V, 50Hz/60Hz
Power consumption 5.5W
Dimensions Width 454x height 140x depth of 391mm
Weight 9kg