Tektronix 5103N

Operating Instructions—
5103N
Fig.
2-4.
Measuring time
duration (period) between
points on
a
waveform.
Fig.
2-5.
Measuring risetime.
center horizontal line. Adjust the horizontal Position con-
trol
to center
the time-measurement
points
within the
cen-
ter eight divisions
of
the
graticule.
4. Measure
the
horizontal distance
between the time
measurement
points. Be sure
the Variable Seconds/Div con-
trol
is in the
Cal position.
5.
Multiply the
distance
measured in step 4 by the
setting
of the
Seconds/Div
switch.
EXAMPLE:
Assume
that the
horizontal distance
between the
time-measurement
points
is
five divisions and
the Seconds/Div
switch is set to .1
ms.
Using the
formula:
p
.
^
horizontal
distance
^
Seconds/Div
(divisions)
switch setting
=
(5)
(0.1
ms)
=
0.5 ms
The period is
0.5
millisecond.
Determining Frequency
The
time
measurement technique can also
be used
to
determine the frequency of
a
signal.
The frequency of
a
periodically recurrent signal is the reciprocal of
the time
duration
(period) of one cycle. Use the following
pro-
cedure:
1. Measure
the period of
one
cycle of
the waveform
as
described in the previous application.
2.
Take the reciprocal of
the
period
to determine
the
frequency.
EXAMPLE:
The frequency of
the signal shown
in Fig.
2-4,
which
has
a
period of
0.5 millisecond,
is:
1
1
Frequency
=
:
—- =
—
=
2 kilohertz
period
0.5
ms
Risetime
Measurements
Risetime
measurements employ
basically the
same tech-
niques
as
the
time-period
measurements. The main
differ-
ence
is the
points between
which the
measurement is made.
The following
procedure gives
the basic method
of
measuring risetime
between the 10%
and
90%
points
of the
waveform.
1
.
Connect
the signal to
the input connector.
2. Set
the Volts/Div
switch and Variable
Volts/Div con-
trol
to
produce a
display
an
exact number
of divisions in
amplitude.
3.
Center the display about the
center horizontal line
with the vertical
Position control.
4.
Set the time-base
triggering controls to obtain a
stable display.
Set the
Seconds/Div switch to the
fastest
sweep rate that will display less than eight divisions
be-
tween the
10% and
90%
points
on the waveform (see Fig.
2-5).
5.
Determine the
10% and
90%
points on the rising
por-
tion
of
the waveform. The figures given in Table
2-3
are for
10% up
from
the start
of
the
rising portion
and 10%
down
from
the top
of
the rising
portion
(90%
point).
2-8