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Products => Test Equipment => Topic started by: Circlotron on September 12, 2020, 03:51:31 am

Title: Rigol DS2072 trigger out duty cycle - meaning?
Post by: Circlotron on September 12, 2020, 03:51:31 am

Got a second scope plugged into the trigger out BNC of the Rigol scope. It is a 3 volt pulse and the thing is, it’s duty cycle changes with both sweep speed and memory depth (which changes sweep repetition rate). I’m putting in a 1kHz 5% duty cycle pulse and if I see only a single pulse on the Rigol screen then the trigger out signal is at 1kHz. That’s okay. But if I wind up the scope timebase so that I can see only the leading edge of the 1kHz pulse from the function generator, the pulse from the trigger output gets narrower and narrower, roughly representing the percentage of displayed waveform vs the remainder of the cycle that is off screen. Is that what it is all about?

Title: Re: Rigol DS2072 trigger out duty cycle - meaning?
Post by: JDubU on September 16, 2020, 12:55:25 am

Makes sense to me.
A trigger-out pulse should appear for every trigger event.  Each trigger event starts a new sweep.  When the sweep ends, the scope must prepare itself for the next trigger.  That would include resetting the current trigger-out pulse so that the next trigger event is guaranteed to be able to produce the rising edge of a new trigger-out pulse.