Sweep - LeCroy PXA125 User Manual

3-68 ArbConnection
parameter. To access the required parameter, click on the button
below parameters sub-group until the LED next to the required
parameter turns on. The value that is associated with the lit LED is
displayed on the digital display. You can use the dial, keyboard, or the
[ ] [ ] keys to adjust the readout to the required setting. After you
modify the reading, press Execute to update the PXA125 with the new
reading.
Normal color of the digital reading is dark blue. If
you modify the reading, the color changes to a
lighter shade of blue, indicating that the PXA125
has not been updated yet with the new parameter.
Pressing Execute will update the instrument and
will restore the color of the digital readout to dark
blue, indicating that the displayed value is the
same as the generator setting.
Also note that the digital readout has an autodetect
mechanism for the high and low limits. You cannot
exceed the limits if you are using the dial but only
if you use the keypad. In case you do, the program
will not let you download an illegal parameter and
you'll be requested to correct your setting.
Direction – Use the keys in this sub-group to program sweep
direction. Up select sweep from start to stop sample clock setting and
Down selects sweep from the stop to start sample clock setting. Refer
to Chapter 3 of this manual to learn more about sweep operation.
Type – Use these keys to select sweep step from two options: linear
and logarithmic.
Mode- The Mode sub-group let you select one of the Sweep
operating modes. You have a choice of continuous, triggered and
gated sweep. Unlike the main trigger function, the trigger modes for
the sweep function operate in continuous mode. For example, if you
place the instrument in triggered sweep, the instrument will idle at the
carrier frequency and execute one sweep cycle when triggered. Refer
to the appropriate section in this manual to learn more about triggered

sweep.

Slope – The Slope sub-group let you select edge sensitivity for the
trigger input of the PXA125. If you click on Positive, the instrument will
trigger on the rising edge of the trigger signal. Likewise, if you click on
Negative, the instrument will trigger on the falling edge of the trigger
signal.
User Manual PXA125
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