
Lo-D DAD-800 |
|
159,000yen(1983 release) |
The compact disk player of No. 2 by which
high-quality sound-ization was attained by the comprehensive technical
capabilities of Hitachi Lo-D.
Three spot schemes laser pickup servo is
adopted.
In this servo, two sublaser spots for a tracking error detection
shifted a little to right and left other than the main laser spot which reads a
signal are arranged. When tracking is being carried out correctly, the reflected
light output of two sublaser spots is the same, but if it shifts even when it is
small, a difference will appear in the quantity of the reflected light from the
pit gathered at the sublaser spots 1 and 2, and an output will become
imbalanced. This detects a tracking error quickly.
The laser light which passed the cylindrical lens has adopted as the focal
error resulting from Hure of the upper and lower sides by the curvature
of a disk the "longwise ellipse -> complete-round -> oblong
ellipse" and the focal signal detector using the property of changing.
According to the form of the laser light included in a
detector, if it is a complete round and is an exact Focus and an ellipse, it is
judged as a focal error, and the error signal is outputted quickly.
The objective lens two-dimensional drive actuator original with a roadeo
to which an objective lens is moved quickly is carried to a tracking error-correction
signal and a focal error-correction signal.
It is an actuator similar to the voice
coil of the loudspeaker, and the tracking Focus with an exact submicron
precision is realized by carrying out the high-speed migration of the lens to a
correction fraction at the 2-way of the upper and lower sides and right and
left.
The Lo-D has adopted LSI and IC which carried out the exclusive
design as all the circuitries, such as a data strobe circuitry which
distinguishes a digital signal, and a digital disposal circuit which carries out
the detection correction of the error and rearranges a signal as a format.
The brushless, the coreless, and the uni-torque motor of a slotless are
carried in the disk motor.
The audio peculiar part, a quality pure Focus
capacitor, the 11th low pass filter which selected every article carefully are adopted as an analog circuit.
An operation of random-memory song
selection, direct song selection, and one-touch song selection, an index search, a manual search, a song selection head-search pause, etc. is possible.
Moreover, the repeat function which can choose all songs / song selection /
1 music / zone is carried.
An output sound volume can be adjusted.
There was a wired remote control unit as an option.
|
Form |
Compact disk player |
<Audio part> |
The number of channels |
Two channels |
Frequency characteristic |
5Hz-20kHz±0.5dB |
Dynamic range |
95dB |
SN ratio |
95dB |
THD |
0.003%(1kHz) |
Separation |
94dB(1kHz) |
Wow and flutter |
Below a limit of measurement (±0.001%W.Peak)
|
<Disk> |
Performance time |
60 minute / single sided (possible for a
maximum of 75 minutes) |
Diameter |
120mm |
<Signal format> |
Sampling frequency |
44.1kHz |
The number of quatizations |
A 16-bit linear / channel |
Transmit bit rate |
4.3218Mb/a second |
<Pickup> |
Scheme |
Objective lens drive system optical pickup
|
Objective lens drive system |
Two-dimensional parallel drive
|
Light source |
Semiconductor laser |
Wavelength |
790nm |
<Synthesis> |
Output voltage |
2.5Vrms |
Supply voltage |
AC100V, 50Hz/60Hz |
Power consumption |
23W |
Dimensions |
Width 435x height 110x depth of 264mm |
Weight |
5.9kg |
Option |
Wired remote control unit returns-to-biases-800 (6,000yen) |
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