Canon A-1 Repair Manual page 142

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76
5V
In
. . .
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5V
Fig. 3-44
5V
5n
..
r;v
Fig. 3-45
S
. . .
..
S
..
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I
,
I
During the 5
mS
that the
MG3 holding current is off,
it
1s held mechanically,
so it shows a smooth curve
without the reverse current
s pike.
This waveform shows both
the "false release" and true
release. The reverse cur-
r e nt spike can be seen in
the true release at the
right edge.
4.
Bias
(4P)
Bias voltage output for the CPU operation.
Bias: 3.5 - 4.0V
5.
SMGl
(5P)
MMl operational signal gate. (See also 3.3.3.)
6. CTST (6P)
Count Start signal for shutter timing. (See also
3.3.2)