Rise Time; Delay Time Position Control Setting; Rise Time, Differential Time Method - Tektronix 2215 Instruction Manual

2215 Operators
10. Record the B DELAY TIME POSITION control dial
setting.
2. Apply a 5-division signal to either vertical-channel
input connector and set the VERTICAL MODE switch to
display the channel used. Ensure that the VOLTS/DIV
Variable control is in the CAL detent.
11. Calculate the time difference between repetitive
pulses using the following formula. NOTE
Time
Difference
(Duration)
/s
second
f dial
\ setting
A SEC/Div\
switch ]
setting /
For rise time less than 0.2 ps per division, the
VOLTS/DIV Variable control may be used to obtain
an exact 5-division display.
EXAMPLE: With the A SEC/DIV switch set to 0.2 ms,
the first B DELAY TIME POSITION dial setting is 1.20
and the second B DELAY TIME POSITION dial setting
is 9.53 (see Figure 23).
Substituting the given values in the time difference
formula:
Time Difference = (9.53 — 1.20) (0,2 ms) = 1.666 ms
Rise Time
The measurement method for rise time is the same as
for time difference between repetitive pulses, except that
the measurements are made between the 10% and 90%
points on the leading edge of the waveform. Fall time is
measured between the 90% and 10% points on the trailing
edge of the waveform.
1. Preset instrument controls and obtain a baseline trace.
Figure 23. B DELAY TIME POSITION control settings.
3. Vertically position the trace so that the zero refer¬
ence of the waveform touches the 0% graticule line and the
top of the waveform touches the 100% graticule line (see
Figure 24).
The 10% point on the waveform intersects the center vertical
graticule line.
The 90% point on the waveform intersects the center vertical
graticule line.
3398-25
Figure 24. Rise time, differential time method.
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