>The CRO signal may be missleading, you need to check if the is set to
ALTernate or CHOP. You need >CHOP to check that the video is in phase, ALT
will always show the two signals in sync as it triggers for >each chanel.
Some CRO's chose between these modes depending on the trace sweep speed.

Only if the scope is set to 'NORM' trigger. My scope lets me trigger on a
single channel and then display both channels on that timebase (using either
ALT or CHOP)

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)

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