Marantz CD-73 - 3. DRAWER MOTOR CONTROL P.W. BORAD WORKING PRINCIPLE; 3.1 Drawer Motor Drive Circuit; C. Explanation of overall operation

Your Marantz CD-73 Compact Disc Digital Audio Player employs
ultra-precise manufacturing techniques and sophisticated digital and
servo technology to assure you an audio output which is the full
equivalent of that at the studio console where the original recording
was made. Your listening room will never be the same again!
Please read this instruction manual carefully before using your
CD-73 Compact Disc Digital Audio Player. This player has been
manufactured with the greatest of care to ensure trouble-free opera-
tion; however, should you encounter any problem, please promptly
notify the store where you purchased the machine or your nearest
Marantz service station.
FEATURES
Ultra-compact laser beam pickup + linear motor mechanism
Marantz has succeeded in developing a mechanism of unprecedented
small size through use of its own independently-developed ultra-
compact laser beam pickup and linear motor mechanism. This
enables slim styling which complements that of other equipment
in your audio set-up.
Easy-loading drawer type disc mechanism
The disc loading mechanism in this player represents a new concept
in loading compact digital audio discs which is based on Marantz’s
many years of experience with cassette decks. When the motor drive
drawer is pulled out, the disc clamper automatically rises and the
front panel tilts. All that is necessary is to set the disc in place.
Three built-in microprocessors
The independent functions of three separate microprocessors are
employed to ensure that the fullest use is made of the potential of
digital! audio recordings.
Ultra-precise servo mechanism ensures perfect tracking
Two high-speed 8-bit microprocessors interact with each other to
assure perfect tracking by the focus servo, radial servo, and platter
servo.
Convenient, 3-way programming capability for disc playback
Together with a random access program, this unit allows three dif-
ferent programs to be stored for playback control. Each program
allows up to 15 selections to be played back in any desired order.
Fully balanced swing mechanism
Use of Marantz’s own fully balanced swing mechanism ensures
superb resistance to vibrations and inclination, as well as making it
possible to increase the speed of random access.
Repeat function
This function makes it possible to repeat your program of playback
selections any number of times.
Large, easy to read display
Large, easy to read display makes it possible to determine the
status of programs or playback at a glance.
Specially developed error correction circuit
Discs are usually contaminated with a variety of foreign matter.
Ordinarily, this degrades the quality of sound; however, this player
includes a specially developed error correction circuit which com-
pletely eliminates the effect of foreign matter by restoring the
audio data to its original condition after detection by the laser beam
pickup.
Ultra-precise disc clamp system
Discs are loaded by simply setting them in place. To achieve this,
an ultra-precise spring-loaded spindle and a magnetic disc clamper
have been developed. Working as a pair, the spindle and disc clamper
assure accurate disc positioning even if the disc is tilted when it is
dropped into place.
Green disc illumination
The disc compartment is illuminated with green light during play-
back. This allows the disc to be viewed from the front or top during
playback.
Energy-efficient solid state laser
Formely, all lasers were based on glass tubes, which required a great
deal of energy to operate. In contrast, the newly developed solid
state laser used in the CD-73 results in a great savings in energy.
1?C bus system for internal communication
The t?C bus system is employed for all communications between
display, control keys and microprocessors. This insures positive,
sure processing for all functions by the microprocessor ‘‘brains’’ of
each section to deliver the ultimate in sound.
Marantz bus system
The Marantz bus system has been introduced in this unit to make
it possible to develop total audio systems in which microprocessors
in each of the components which are equipped with this system
actively communicate to provide easy listening and remote control
capability.
a m7
“FORE USING
e@ Place of installation
To ensure long unit life, avoid using the CD-73 in locations such
as:
e@ Locations which are exposed to direct sunlight or heat from
radiators and the like
@ Locations which are poorly ventilated or highly humid
e Unstable locations which are tilted or subject to excessive
vibration
@ Locations near windows or other places where there is any
danger of the unit being exposed to rain or water
e@ Be very careful to avoid touching the pickup or lens with your
fingers or other objects.
e@ This is an ultra-precise mechanism which reads information
on the disc with an accuracy of 1 um (1/1000 mm).
@ If an excessive amount of dust accumulates on the lens,
carefully clean it with a camera blower brush.
e Electrical precautions
e Avoid touching the unit when your hands are wet.
e@
When
pulling
the
power
cord
out
of
its
wall
socket,
be
sure
to
pull
on
the
plug
and
not
on
the
cord.
Failure
to
handle
the
power
cord
properly
can
result
in
a
shock
or
fire
hazard.
e@
Make
a
habit
of
pulling
the
plug
out
of
the
wail
socket
when
you
go
out
for
an
extended
period
of
time
(holidays'for
example).
e Maintenance
e
Do
not
attempt
to
service
or
repair
the
pickup
element
or
any other internal components. All repairs must be made by
a competent, authorized technician.