4-12. Time Difference On Single Waveform; Rise Time - Tektronix 2215A Operator's Instruction Manual

INTENSI FIED
/ ZONE
A TRACE
B TRACE
r
-
ALT HORIZ DISPLAY
\ VERTICAL
REFERENCE LINE
C4207-23
Figure 4-12. Time difference on single waveform.
9. Adjust the B DELAY POSITION control clockwise to
move the intensified zone to the leading edge of the second
point of interest (on the A trace); then fine adjust until the
rising portion (on the B trace) is centered at the same conve-
nient vertical graticule used in preceding step 7.
10. Record the B DELAY TIME POSITION control dial
setting.
11 . Calculate the time difference between repetitive
pulses using the following formula.
Time (second first ) (A SEC/DIV)
Difference
=
dial - dial switch
(Duration) setting setting setting
EXAMPLE: With the A SEC/DIV switch set to 0.02 ms
per divisions the first B DELAY TIME POSITION dial set-
ting is 1.20 and the second B DELAY TIME POSITION
dial setting is 9.53 (see Figure 4-13).
Substituting the given values in the time difference
formula:
Time Difference
=
(9.53 - 1.20) (0.2 ms/div)
=
1.666 ms
Operating Procedures-2215A Operators
DIAL READING
AT POINT A
DIAL READING
AT POINT B
C4207-24
Figure 4-13. B DELAY TIME POSITION control settings.
Rise Time
Rise-time measurements use the same methods as time
interval on single waveform, except that the measurements
are made between the 1 0% and 90% points of the low to
high transition of of the selected waveform. Fall time is mea-
sured between the 90% and 10% points of the high to low
transition of the waveform.
1 . Preset instrument controls and obtain a baseline
trace.
2. Apply an exact 5-division signal to either vertical-
channel input connector and set the VERTICAL MODE
switch to display the channel used.
3. Set the appropriate VOLTS/DIV switch and variable
control for an exact 5-division display.
4. Vertically position the trace so that the zero reference
of the waveform touches the 0% graticule line and the top of
the waveform touches the 100% graticule line.
5. Set the A SEC/DIV switch for a single-waveform dis-
play. Ensure that the SEC/DIV Variable control is in the CAL
detent.
6. Select ALT HORIZONTAL MODE and set the
B SEC/DIV switch to spread the rise-time-measurement
portion of the display as much as possible.
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