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GLout pin
output waveform
Main Ports
SPDL-MUTE (pin !¶)
From the viewpoint of performance of the set, the disc must
not move nor sway when the disc table opens. These
problems however occur in the actual case due to the offset
voltage generated and the voltage generated because of the
positional relation between the BSL coil and Hall element.
The spindle motor driver (IC104, IC105) is therefore muted
while the tray is open. Pin !¶ provides the timing for this.
OPEN
Reverses after a
certain
eriod of time.
SP MUTE
(MUTE ON)
CLOSE SPINDLE
KICK
Reverses after a
certain
eriod of time.
PLAY
Time while the disc
can be seen
(Estimate).
The spindle
motor driver is
muted during
this time.
BLANK (pin @¡)
This port is required because the display tube in this set
static-lights up and a dedicated screwdriver is required. It is
basically a RESET pin. But as problems will occur if used
also as RESET, timings are specially provided using the
micro-processor.
SENSER SW (pin @¶)
As IC261 IS471F operate in pulse as shown in the figure, the
sound quality may be affected if operated constantly. As the
purpose of IC261 is to detect if the presence of the stabilizer,
it should be operated only when the tray is drawn in. IC261
o
it is “L”.
Ee
0
Eep
Eed
Time
Eep is the luminance of the signal light tuned with the low
level timing of the GLout pin output.
Eed is the luminance of the D.C. light. The light source is
the infrated-emitting diode (λp=940 nm).
*
SENSER (pin @•)
The results of the detection of IC261 IS471F is output to this
pin. It becomes “L” when there is no stabilizer (when light
reaches). The next process of imposing the next focus is not
performed. (Effective only when pin @¶ is “H”.)
Therefore, it must be noted that if PLAY is performed when
the servo board at the top of the CDM is not assembled
properly, the detection circuit operates and this pin does not
operate.
It is does not operate, refer to 1. SERVICING NOTES ” Prep-
arations for Adjustment and Measurement” on page 3.
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