Tektronix 2245A Operator's Manual page 77

3. Press AUTO SETUP button.
4. Set the CH 1 VOLTS/DIV and VOLTS/DIV VAR controls to provide an
exact five-division vertical display.
5. Use the CH 1 Vertical POSITION control to place the negative amplitude
of the signal on the 0% reference line and the positive amplitude on the
100% reference line.
6. Increase the SEC/DIV setting to stretch out the rising edge of the
waveform as much as possible to improve the cursor placement
accuracy (see Figure 5-4).
7. Adjust the Trigger LEVEL control, if necessary, to get the 10% level on
screen.
If measuring fall time, use negative SLOPE. This places the
trigger point at the beginning of the sweep so that when the
SEC/DIV setting is advanced, the slope of interest remains
within the viewing area.
8. Increase the A INTEN control if necessary to brighten the beginning of
the trace, and use the Horizontal POSITION control to place the 50%
level (center) of the rising edge of the waveform at the center vertical
graticule line.
9. Press TIME button to display the time cursors.
10. Use the K- OR DELAY control to align the first cursor to the rising edge
at the point where it crosses the 10% reference graticule line. Then use
the -») control to align the second cursor to the point where the rising
edge crosses the 90% graticule line and read the rise time displayed in
the top line of the crt readout (see Figure 5-4).
2245A Operators
NOTE
Basic Applications
5-7