Delayed Sweep Time Measurements - Tektronix 7B70 Time Base Instruction Manual

Operating Instructions-7B70 (SN B205000 and Up)
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DELAY T I M E M U L T I P L I E R
dial settings
Fig. 2-1 1. Measuring risetime. Fig. 2-12. Measuring time difference using delayed sweep.
Delayed Sweep Time Measurements
NOTE
The delayed sweep mode can be used to make accurate
Do not change the A LEVEL control setting or the
time measurements. The following measurement determines
horizontal POSITION control setting in the following
the time difference between two pulses displayed on the
steps, as the measurement accuracy will be affected.
same trace. This application may also be used to measure
time difference from two different sources (dual-trace) or
to measure time duration of a single pulse. See Section 1
for measurement accuracy.
6. Turn the DELAY-TIME MULTIPLIER dial to move
the intensified portion of the A sweep to the first pulse.
1. Connect the signal to either vertical plug-in. Set the
Indicator Oscilloscope vertical MODE selector to display
the plug-in being used. Set the horizontal MODE selector to
7. Adjust the DELAY-TIME MULTIPLIER dial to move
CHOP or A L T (see Oscilloscope Manual discussion on hori- the pulse (or rising portion) of the B sweep t o the center
zontal mode switching) to display both Time-Base sweeps.
vertical line. Note the setting of the DELAY-TIME MULTI-
PLIER dial.
2. Set the VOLTSIDIV selector to produce a display
about three divisions in amplitude (see Fig. 2-12).
8. Turn the DELAY-TIME MULTIPLIER dial clockwise
until the second pulse is positioned to this same point (if
several pulses are displayed, observe the intensified portion
3. Set the A TIMEIDIV to a sweep rate which displays
of the A sweep t o locate the correct pulse). Again note the
about six divisions between pulses. Adjust the A Triggering
dial setting.
controls for a stable display.
9. Subtract the first dial setting from the second and
4. Set the A Time-Base B DELAY MODE selector to B
multiply by the delay time shown by the A TIME/DIV
STARTS AFTER DELAY.
selector. This is the time interval between the pulses.
5. Set the 7B70 (B) TIMEIDIV t o a setting 1/100 of the Example: Assume the first dial setting is 2.23 and the
A TIMEIDIV sweep rate. This produces an intensified por-
second dial setting is 7.73 with t h e TIMEIDIV set to 5 ps
tion about 0.1 division in length.
(see Fig. 2-1 2).
Scans by Artekhledia O 2006