Instructions

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4.3.2 CYCLE & FREQUENCY MEASUREMENTS
Shown in Fig 4-6, frequency measurements are made by measuring the time period of
one cycle of waveform (T), and calculating the frequency that equals the reciprocal of the time
period. For example, T=16µS, then frequency is:
1
F =1/T = ------------------ = 62.5 KHz
16 ×10
-6
4.3.3 PULSE RISE TIME AND FALL TIME MEASUREMENTS
For rise time and fall time measurements, the 10% and 90% amplitude points are used as
starting and ending reference points.
(1) Apply a signal to the input jack [19].
(2) Use the VOLTS/DIV and VAR controls to adjust the waveform peak to peak height to
five divisions.
(3) Adjust vertical position so that the tops of the waveform coincide with 100% point,
while the bottoms of the waveform coincide with 0% point.
(4) Adjust Sweep switch to obtain the positive-going direction or negative-going direction
of the waveform on the screen.
(5) Use the horizontal POSITION control to adjust the 10% points to coincide with a
vertical reference line.
(6) Measure the horizontal distance in divisions between the 10% and 90% points on the
waveform (divisions).
(7) Pulse rise time and fall time measurement is calculated by the following equation:
Horizontal distance (div) × sensitivity (Time/div)
Rise Time = -----------------------------------------------------------
Horizontal factor
For the example shown in Fig.4-7, the horizontal distance from 10% to 90% is 2.4
divisions, the sweep TIME/DIV setting is 1µS/DIV, factor x 1. The rise time is
calculated as follows:
1µS/DIV × 2.4DIV
Rise Time = ------------------------------ = 2.4µS
1
Fig. 4-7
10%
90%
100%
2.4DIN