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4.2 CIRCUIT OPERATIONS
The operations described in the section assume
that a 17cm record is being played at 33 rpm.
= Auto Lead-in Operation
. When
the START/STOP
button (switch S5) is
pressed, pin 26 of PD6005 is switched to L level,
resulting in pin 15 also being switched to L level,
thereby turning the lead-in indicator LED (D10)
on,
At the same time, pin 13 is also switched to
L level, resulting in the motor ass'y (IC4) being
activated via Q6.
The phono motor is thereby started (and turn-
table rotation commenced).
2. When the turntable attains the rated rotational
speed, the quartz lock indicator
LED
(D9) is
turned on.
Pin 35 of IC1 is also switched to L level at the
same time, resulting in pins 9 and 10 of the same
IC being switched to L level, thereby commenc-
ing the tonearm lead-in movement.
(See page 12
for details of drive coil activation).
be
If the tonearm has been inadvertently left
clamped into the arm rest at this time, pins
15 and 16 of IC1 will commence
to switch
_ back
and
forth
between
H
and L
levels
approximately
7 seconds after the START/
STOP
button is pressed thereby causing the
lead-in indicator LED (D10) and the lead-out
indicator LED (D11) to flash on and off. And
if the tonearm has still not left the arm rest
after a further 10 seconds, the PL-L800 will
cancel the play preparations.
Note that play preparations will also be can-
celled if the turntable fails to attain the rated
rotational
speed
within
about
17
seconds
after pressing the START/STOP button.
3. When the tonearm moves across to the record,
the
lowering
position
sensor
(LED
D52
and
photo-sensitive
transistor
Q52)
first applies a
30 cm lowering position signal, and then a 17cm
lowering position signal to pin 38 of IC1 (L level
signals). (With 17 cm records, IC1 counts the
seconds
signal to judge the lowering position).
4. When the tonearm reaches the lowering position,
pins 9 and 10 of IC1 are reverted to H level, the
current applied to the relevant drive coil cut,
and
the
lateral
movement
of
the
tonearm
consequently halted.
IC1 pin 15 is also reverted to H level, resulting
in the lead-in indicator LED (D10) being turned
off,
PL-LSOO
5.1C1 pin 33 is switched to H level while pin 32
is switched to L level (pin 7 of IC6 BA6208
to H level and pin 8 to L level), resulting in the
elevation
geared
motor
turning
in the down
direction for the tonearm to be lowered onto
the record.
Since
IC6
pin 7 has also been
switched to H level, the up indicator LED (D15)
is turned off at this time.
6. As the
geared
motor
continues
to turn,
the
elevation
cam
eventually
presses
against
the
down
detector
switch
(S8), resulting in IC6
pin 2 and IC1 pin 33 being switched to L level,
thereby stopping the geared motor. The tonearm
consequently
lands
gently
on
the record
for
start of play.
rs
|
If the
START/STOP
button
is pressed
again during this auto lead-in operation, the
PL-L800 switches over to the auto stop oper-
ational mode.
And if the locate-in or locate-
out button is pressed during auto lead-in, the
PL-L800
cancels the play preparations, and
switches directly to locate operational mode.
|
= Locate-in and Locate-out Operation Modes
1. If the locate-in or locate-out button is pressed
continuously while a records is being played, the
tonearm
is lifted away from the record, and
locate operational mode is commenced.
2. The locate-in and locate-out buttons are double-
action switches. If pressed (continuously) to the
first level, the tonearm will move slowly, but if
pressed (continuously) to the second level, the
tonearm will move at a faster rate.
3. When the locate-in button (switch S6) is pressed
continuously
to the first level, IC1 pin 28 is
switched to L level, resulting in pin 9 also being
switched
to L level, and the tonearm conse-
quently being moved towards the center of the
record.
At the same time, IC1 pin 15 is slowly
switched to H and L levels repeatedly, resulting
in the lead-in
indicator
LED
(D10)
blinking
on and off repeatedly.
4. If the locate-in button is pressed in further to
the
second
level
(and kept
in this position)
IC1 pins 9 and 10 are both switched to L level,
resulting in the tonearm being moved inwards
at a faster rate.
At the same time, IC1 pin 15 is
switched
rapidly and repeatedly
to H and L
levels, resulting
in the lead-in
indicator
LED
(D10) flashing on and off more rapidly.
5. When
the
locate-out
button
(switch
$7)
is
pressed continuously
to the first level, IC1 pin
11 is switched to L level, while if pressedto the
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