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FEATURES
AND
FUNCTIONS
1-9
SAMPLE AND
HOLD
(S/H)
•
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•
S/H
OUTPUT
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Converts input
voltage
signal
into
stepped output
signal.
it
t:\ti7lTT
t-MLJT
•
CLOCK FREQUENCY
Used
to adjust
frequency
of
sampl-
ing
signal
(determines
sampling
rate).
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yf
•
SYNCHRO
SWITCH
If
the
input
signal
is
cyclic,
this
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synchronize
the sampl-
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ut
sig
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will
repeat
itself in
regular cycles
also.
1AHPU4
•
INPUT
JACK
For
voltage
signal to
be sampled.
fig.
22
S/H
C)
30
I
25-
•
15-
•
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15
(A)
21
(K|)
(O'CLOCK)
6
9
12
15
18
21
(B#)
(
B)
(o-
clock;
fig.
24 S/H
experiment
(S/HCD3I5*)
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fig.
23
Two
graphs
(
2
OCO^-5 7)
SG
WAVE FORM
1-9
Sample and Hold
(S/H)
Look
at
graphs
"A"
and
"B"
in
figure 23.
Graph
"A"
is
one
day's
temperature
changes
drawn by
an automatic
recording
thermometer.
Graph "B"
is
a
bar
graph
that
you
could
draw
if
you
checked
the
temperature every
three hours.
What
the
sample and hold
circuitry
does
is
convert graph
"A"
into
graph "B".
In
a synthesizer,
graph
"A"
corresponds
to
the kind of
continuously changing output
signal
produced by
a
modulation
generator.
Graph
"B"
corresponds
to
the stepped
output
signal
produced by
the
S/H
sec-
tion.
As
its
name
implies,
the
S/H
section
sam-
ples
the
input
signal at
regular
intervals
and
holds
the voltage
at that level until
the
next
sample
is
taken.
The
regular
intervals
(every three
hours
in
our temperature
ex-
ample)
are
determined by
the
CLOCK
fre-
quency
knob.
With
the
setting
shown
in
figure
24,
you
can use
the
S/H
to
cause pitch
variations.
Try
using different
MG-1
waveforms
and
see
what
happens*to the
S/H
output.
If
you
turn
on
the
SYNCHRO
switch
and
use white or
pink
noise
(which
is
not
cy-
clic)
as
the
S/H
input
signal,
both
the
pitch
variations
and
the clock
frequency
will
be-
come
random-
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