Agilent Technologies E8257D PSG manual Setting the Polarity of an External Trigger, Gated Mode

Basic Digital Operation

Triggering Waveforms

Setting the Polarity of an External Trigger

Gated Mode

The selections available with the gate active parameter refer to the low and high states of an external trigger signal. For example, when you select High, the active state occurs during the high of the trigger signal.

ARB Formats	When the active state occurs, the PSG stops the waveform file playback at the last
	played sample point, and restarts the playback at the next sample point when the
	inactive state occurs.

Real- Time Custom When the active state occurs, the PSG transmits the data pattern. When the inactive state occurs, the transmission stops at the last transmitted symbol, and restarts at the next symbol when the active state occurs.

Continuous, Single, or Segment Advance Modes

The Ext Polarity Neg Pos softkey selections refer to the low (negative) and high (positive) states of an external trigger. With Neg selected (the default), the PSG responds during the low state of the trigger signal.

Using Gated Triggering

Gated triggering enables you to define the on (playback) and off states of a modulating waveform. This example uses the factory supplied segment, SINE_TEST_WFM.

1.Connect the output of a function generator to the signal generator’s rear- panel PATTERN TRIG IN, as shown in the following figure.

This connection is applicable to all external triggering methods. The optional oscilloscope connection enables you to see the effect that the trigger signal has on the RF output.

2. Preset the signal generator.

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