The edge trigger is the simplest trigger type. An 
edge trigger triggers when the signal crosses an 
amplitude threshold with either a positive or 
negative slope.  
The Delay trigger works in tandem with the edge 
trigger, by waiting for a specified time or number 
of events before the edge trigger starts. This 
method allows pinpointing a location in a long 
series of trigger events. 
Note: when using the delay trigger, the edge 
trigger source can be any one of the channel 
inputs, the EXT input or the AC line.