Time Measurements - Tektronix 2245A Operator's Manual

Operators Familiarization
The voltage measurement system measures the equivalent voltage differ­
ence between two horizontal cursors when the Horizontal MODE Is in A or
X-Y. Both cursors are positioned by the |<- OR DELAY control and the
delta cursor is positioned by the -H control. When the cursor volts measure­
ment is first turned on, the peak voltages of the source channel signal are
measured, and one cursor is placed at the most positive peak and the other
is placed at the most negative peak.
The CLEAR MEAS'MT button turns off the measurement.
Press the TIME button to display the time measurement cursors. The se­
lected measurement type and value are displayed at the top of the screen.
Changing the Horizontal MODE from B to X -Y will cancel a
time measurement mode. Set Horizontal MODE back to A,
ALT, or B and press the TIME or 1ITIME button to reacti­
vate the time measurement mode.
Vertical cursors are displayed for use in setting the time-measurement
points in A Horizontal MODE. In ALT Horizontal MODE, the delay measure­
ment is made using either the intensified zones as the measurement points
or the alternate B delayed sweeps. For B Delayed Horizontal MODE, the
delayed sweeps only are available for making timing measurements.
When the Horizontal MODE is either ALT or B, the B Trigger MODE must be
set to RUNS AFTER (if not, the following message will be displayed: " USE
RUNS-AFTER-DELAY TRIG MODE" ). If the B Trigger MODE is switched
away from RUNS AFTER using the front panel Trigger MODE buttons, the
selected TIME or 1/TIME measurement will be canceled. Pressing the TIME
or 1/TIME button again will reactivate the measurement only if the B Trigger
MODE is set to RUNS AFTER.
In the A Horizontal MODE, cursors are used to make the time measure­
ments; in ALT or B Horizontal MODE, the timing measurements are made
using either the intensified zones that appear in the A sweep trace in ALT
Horizontal MODE or the B delayed waveforms in either ALT or B Horizontal
MODE. The |<- OR DELAY control positions both cursors or delay times
(reference and delta) together, and the -»( control positions the independ­
ent delta cursor or delay when TIME or 1/TIME measurements are se­
lected.
3-6

Time Measurements

NOTE
2245A Operators