I'm probing a point with 230V RMS voltage inside a machine (don't worry, I'm using a 100:1 CAT 3 probe rated at 600V), and would like to trigger my oscilloscope at the point when this signal is interrupted. That is, the sine wave ends and becomes a flat line.
I have a Rigol DS1054Z oscilloscope. Is there some clever way to arrange such a trigger? I thought perhaps I could use the slope trigger, but I didn't get it to work.