Datapulse 101 - Page 28

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i
n
V]:
1—171
«II
n
l
All
r;
C
C
F3
W
C
Use
the
scope
to
verify
that
the
pulse
width
is
1.
0
microseconds.
If
the
setting
is
incorrect,
adjust
R91
(the
width
calibration
potentiometer).
R91
is
mounted
on
the
circuit
board
near
the
POWER
switch,
labeled
WID
on
the
top
and
accessible
from
the
bottom
as
a
screwdriver
adjustment.
CAUTION
Be sure the PULSE WIDTH vernier is
fully clockwise befoie adjusting R91.
Switch
the
PULSE
WIDTH
selector
to
10
uS
and
the
REPETITION
RATE
selector
to
10
KHz
with
both
verniers
fully
clockwise.
Verify
that
the
pulse
width
is
10
microseconds.
Set
the
PULSE
WIDTH
selector
to
0.1
MS
and
the
REPETITION
RATE
selector
to
l.
0
KHz
with
both
verniers
fully
clockwise.
Verify
that
the
pulse
width
is
0.
1
milliseconds.
Turn
the
PULSE
WIDTH
selector
to
l.
0
M5,
the
REPETITION
RATE
selector
to
0.1
KHz
and
both
verniers
fully
clockwise.
Verify
a
pulse
width
of
1.
0
milliseconds.
Switch
the
PULSE
WIDTH
selector
to
10
MS
with
its
vernier
fully
clockwise
and
turn
the
REPETITION
RATE
vernier
fully
counterclockwise
with
its
selector
set
to
0.
1
KHz.
Verify
a
pulse
width
of
10
milliseconds.
Set
the
PULSE
WIDTH
selector
to
0.
1
us
and
the
REPETITION
RATE
selector
to
l.
0
MHz
with
both
verniers
fully
clockwise.
Verify
a
pulse
width
of
0.
1
microseconds
that
goes
down
to
less
than
30
nanoseconds
when
the
PULSE
DELAY
vernier
is
turned
fully
counterclockwise.
If
not,
trimmer
capacitor
C90
should
be
adjusted
for
the
proper
width.
C90
is
on
the
pulse
width
control
assembly
and
is
accessible
from
the
top
as
a.
screwdriver
adjustment.
NOTE
Use a nonmetalic insulated screw—
driver for this adjustment.
CAUTION
Be sure the PULSE WIDTH vernier is
fully clockwise before adjusting C95.