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1. When the POWER Switch is Switched ON
Then the POWER switch is switched on, * bV is
applied to pin 1 (Vcc) of IC401. During the initial
period when pin 1 voltage is being increased from
0V to 5V (approximately from 0.6V to 2.4V) the
IC's internal reset circuit is activated, putting the
IC into stop status which is maintained for about
four seconds. During this time, Do change can be
effected by pressing any of the other operation
control buttons.
2. Play lVlode
When the PLAY button is pressed, the level of
pin 5 (PIEY)
of IC401 is switched to ,,L,, level,
and the level of pin 24 (PINCH SOL) to ..H"
level. Q503 is turned on and the pinch roller
activated. In
addition, IC401 pin 27 (LINE
MUTE) is opened 416ms after the PLAy button
is pressed, thereby releasing the line mute status
to enable play mode operations to commence.
A L T N E
g/OUTPUT
F i g . 6 - 5
P L A Y m o d e o p e r a t i o n
3. Recording Mode
When a cassette half with its erasure prevention
tabs intact is loaded in the deck, pin B (AR) of
IC4OL is switched to ('H" level, thereby enabling
the deck to be switched to recording mode.
When the REC button is pressed, IC401 pin 4
tnEel
is changed to "L" level. PitjlO
(REC) is
also changed to "L" while pin l-g (REC) is open.
As a result, the REC indicator lights up and the
reed relay (RY501)
is switched off,
therebyT
7 switching the signal path to the recording circuit.
And the IC401 pin 24 (PINCH SOL) changed to
'6H" level,
tape transport is commenced. pin 22
(BIAS OSC) is opened 52ms after the REC button
is pressed, thereby activating the bias oscillator.
Pin 27 (LINE MUTE) and pin 28 (REC MUTE)
are opened 416ms after the REC button is pressed,
thereby releasing the line mute and recording mute
status to permit recording to start.
P I N C H S O L .
+12v A)
L I N E I N P U T
' H ' A C T V E
B|AS OSC.
P I N C H
P L A Y
S O L . ,
- ' l - - - - - - - - { 1
LINE MUTE
Llct6msl-
(oPEN) RTE
(GNO) REC
fi-0-
CASSETTE HAtf
WITH E.P TABS
IS LOADEO
PUSH UP
HEAO BASE
AAIO PINCH
ROLLER
Fn
prNcH
SOL. z
ie;ri5 bsc.
r-152m# - -
I
r44,t6 rnsf --
I REC MUTE
I
I r-rrue uure
)-lqe.n,t!, -
nEi
t
|
^-^
L - - - - - - r
REC
REC/P B.
HEAD
TO OPEN
( ' H ' L E V E L )
F i g . 6 - 6
R E C m o d e o p e r a t i o n
H ' A C T I V E
.\LINE
g/UJTPUT
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