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When the tonearm reach-
es the lead-in position
during its FWD action
in the auto mode, this
cancels the FWD and
REV modes and indicates
the arm DOWN operation.
5-5 Lead-In and lead-out sensor and circuit
+7.8V
igger
Position sensor
SIZE SELECT
ow
R137 1M
30cm IN
17em IN
to C1038)
Ic1028)
lotonin
11 LEAD-IN
GATE
'(101g
2
30cm OUT
R119
10103
10K
10102 M/A Latch
Riaz
0108
AUTO OUT)
;
-
rus
oD |
cc}
Wr
a
Position detection by
1k
of
contact between the
AN
op
R133 Q109
57
3
i
MANUAL OUT)
20K
2
Q
tonearm and the board
Fae mod
3
D108
:
Sa
aro
[indication
fe
oo
to 101088
toilG|o6ue
z
R182
;
s
STOP/REV SW
Ie1o110
11036)
ist
2
330
ios | 10K
©1052)
(This cancels the FWD)
soo
=
and REV modes.
Initial Reset
(from 1010311) aK
This turns ON the STOP switch during
When power failure occurs during
play, when the tonearm is not at
its rest, it returns the tonearm by
play in the auto mode. When the tone-
ON7.5V
arm reaches the lead-out position, it
cancels the FWD mode and returns
the tonearm by the arm REV and UP
the power recovery.
Fig.
Fixed electrodes
Wire sensor (Brush)
Placed at lead-in and
lead-out positions
Fixed axis
Circuit Boad
'Tonearm Carrier
Fig. 12
The
position sensor shown in Fig. 12 detects the
predetermined
positions in combination with the
wire sensor (brush) located at the rear part of the
carrier and the electrodes fixed at the lead-in and
lead-out positions (for 30 cm and 17 cm records)
as shown in Fig. 11.
At power ON, the tonearm enters the auto mode.
When
the START
switch is pressed, the tonearm
indication.
11
moves
in the FWD
mode.
Thereupon, when the
SIZE
select switch
is set to 30",
the position
sensor turns ON with "30 cm IN" and enters as
signal LEAD-IN
the ''H'' pulse into pin 12 of lead-
in gate 1C104 which is timed by Schmitt trigger
1C103C. At this time, since signal FWD
is "'H"
(FWD mode) and signal AUTO
OUT is also "'H"
{auto mode), signal LEAD-IN GATE OUT (pin 10
of 1€104) becomes ''H'', thus the FWD and REV
modes are canceled
(the stoppage of the tonearm
motion)
and indicates the arm DOWN
operation
so that the play
starts at the "30 cm"
lead-in
position.
Next, signal LEAD-OUT at ''H'' from the position
sensor becomes
the lead-out
(return) indication
signal through
D105 and
R117
which
in turn
indicates the arm
UP and REV operation to the
respective circuits. At this time, the MANUAL/
AUTO
(M/A)
latch is set to the auto mode by
signal LEAD-OUT.
In addition, when the stop operation is indicated
by the STOP/REV switch or power failure occurs
with the tonearm
not placed at its rest (the play
mode), the lead-out operation is also performed by
the initial reset indication for power recovery.
HIZ=
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