LASER BEAM INFORMATION --------------------- _
Operation Explanations
The operation sequencefrom magazineinstallation to laser
beamoutput is explained below.
(1) When a magazineis installed with inserted power plug
and the power switch (5901) set to ON, 5356,357
becomesON, and IC302 detects that a magazinehas
beeninstalled.
(2) When an operation button (pLAY /PAUSE, INTRO·
SCAN, RANDOM PLAYI ispressed,this isdetected by
IC302, MECUP
=
"L", MECDWN
=
"H" is obtained,
and
@
=
"L
n,
@=
"Hn
is reachedfor IC305.
Then the disc selection motor runsand the mechanism
assemblyrises.
(3) Passageof the gear slot is detected by PH1 with
PHOTO
=
"L" during rise of the mechanismassembly,
and asthe position of the first disc isreachedwhen this
has occurred twice, MECUP
=
MECDWN
=
"H" is
obtained,
(1)
=
@
=
"L" is reachedfor IC305, and
the disc selection motor and the mechanismassembly
stop.
(If the disc selection key is pressedbefore step (2), the
mechanismassemblymovesto that position.)
(41
Next, TRYIN
=
"H" and TRYOUT
=
"L" is obtained
for IC302. Then
®
=
"L" and
@
=
"H" isput out
by IC304, the loading motor runs, and the tray is
pulled out from the magazine.
(5) When the tray has been pulled out from a magazine
completely and chucking hasbeencompleted, 5353 be-
comes ON. When this is detected, TRYIN
=
TRYOUT
=
"H" is reached,
(3)
=
@
=
"L" is reachedfor
IC304, and the loading motor and the loading mecha-
nism stop.
(6) Next, LDON
=
"L" is reached by IC302. Then the
APC circuit of IC101 operates,power issuppliedto LD
from Q101, anda laserbeamisemitted.
Protection Operation
(1) After completion of play and before the tray isstored
in the magazine, LDON
=
"H" is reachedby IC302,
and the LD laseroutput is stopped.
(2) After item (6) of the above operation explanation,
IC302 reachesLDON
=
"H" after severalsecondsif it
isdetected that there isno discon the tray.
LASER BEAM DESCRIPTION AND HANDLING OF MAIN PARTS _
PICK-UP HANDLING, REPLACEMENT AND SERVICE
NOTES
• Preparations
The compact-disc player incorporates a great many ICs
and LSls, as well as the pick-up (laser diode).
Because these components are extremely sensitive to
static electricity and therefore can be damaged by a high-
voltage concentration of static electricity, the greatest
care is necessary for their handing. In addition, many high-
precision components, such as the lens, are used in the
pick-up.
flesist.nee (1
Mnl
(1) The compact-disc player and its components must
never be repaired or stored in places where the
temperature or humidity is high, in places where
there is a strong magnetic field, or where there is ex-
cessive dust.
(2) Before making any replacement of acomponent, first
disconnect the power cord's plug from the electrical
outlet.
(3) All equipment, measuring instruments and other
tools must be grounded.
(4) The workbench must be covered by a conductive
sheet and grounded.
(5) In order to prevent AC leakagefrom a soldering iron,
metallic tools must be grounded.
(6) Workers must be grounded.
(7) The laser beam from the
pick-up
must never be per-
mitted to enter the eyes directly, and should not be
allowed to contact the skin.
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