Hmm, it's a clever hack, but they would use an oscilloscope with an "External trigger" input, like most of the older Rigols. That would let you use the full sample rate without needing to trigger from CH2
Even modern entry level Rigol scopes have external trigger inputs. I've got like one step up from the cheapest model and it has an external trigger input. I think the idea there is that you'd use a bunch of these scopes for the QA on an assembly line. there's a bunch of pass/fail features I've never once touched too.
Doxin|4 months ago