Channel Mag Trigger Style (Trigger)

The Channel Mag trigger style is available for the following configuration:

2-channel hardware
input channel is I+jQ (ch1+j*ch2)
hardware only supports triggering on the I or Q signal separately, and not the combined I+jQ signal

The Channel Mag trigger only triggers when the signal is within the specified frequency span, as shown in the following block diagram:

$image\trig_ChannelMag_wmf.jpg$

The Channel Mag trigger is usually used with amplitude modulated (AM Amplitude Modulation - CW modulation using amplitude variation in proportion to the amplitude of the modulating signal. Usually taken as DSB-LC for commercial broadcast transmissions and DSB-SC for multiplexed systems.) or burst signals. This trigger style triggers the VSA when the input signal is within the current span, AND the input signal is varying in amplitude, AND the trigger conditions are met. The trigger conditions that can be specified are level, slope, delay, and hold-off.

With Channel Mag, the magnitude of the signal must vary to trigger the VSA. The magnitude of the signal varies when the input signal switches on and off or if the input signal is AM modulated.

Trigger hold-off is often used with Channel Mag. If a burst is being used to trigger the VSA and the burst contains more than one valid trigger edge, trigger hold-off can be used to ignore all but the first trigger edge.