Operating Instructions
—7B53A/7B53AN
Operators
Pulse
Jitter
Measurements
In
some
applications it
is necessary
to measure the
amount
of jitter on the leading edge
of a pulse or jitter
between pulses.
1.
Connect
the signal
to be displayed to the input
connector
of
the vertical unit. Set the Vertical and
Horizontal Mode switches on
the
indicator oscilloscope to
display the plug-in units used.
2.
Set
the
Volts/Division switch on
the vertical unit to
produce a display about 4 divisions in amplitude.
3.
Adjust the
MAIN TRIGGERING
controls for a stable
display.
4.
Set
the
TIME/DIV OR DL Y TIME
switch to a sweep
rate
which
displays the complete waveform
(see Fig.
1-16A).
5.
Pull out the
DLY'D Time/Division switch for the
INTEN
Display Mode.
10. Pulse jitter is
shown by horizontal
movement on the
pulse (take into
account inherent jitter of delayed sweep).
Measure
the amount of horizontal movement. Be sure that
both
vertical and horizontal VARIABLE controls are set to
CAL.
11. Multiply
the distance measured in Step 10 by the
DLY'D Time/Division
switch
setting to
obtain pulse jitter
in
time.
Example.
Assume
that the
horizontal movement is 0.5
division
(see Fig. 1-18) and the
DLY'D Time/Division
switch
is .5 microsecond.
Using the formula:
Pulse
Jitter
=
horizontal
jitter
X
(divisions)
DLY'D
Time/Division
setting
Substituting
the
given values:
Pulse
Jitter
=
0.5 X
0.5 microsecond
The pulse jitter is 0.25 microsecond.
6. Position
the start of the intensified portion with
DELAY
TIME MULT dial to
the part
of the display to be
magnified.
7.
Set
the
DLY'D Time/Division switch to a setting
which intensifies
the
full portion
of the display
to be
magnified. The start of
the intensified trace will remain
as
positioned
in
Step 6.
8.
Press
in the DLY'D Time/Division switch for the
DLY'D SWP
Display Mode.
9.
Slight
readjustment of
the MAIN TRIGGERING
LEVEL
control
may be necessary
to produce as stable a
display
as possible.
Fig. 1-18.
Measuring pulse jitter.
□
Digitally
signed
by
1-21
