There is no common starting point for them either, I assume.

You will never synchronize them except during times of coincidence and that would be briefly.

If you fed a common clock to two dividers to develop those signals, you certainly could synchronize them, if synchronizing them is important.

Such a simple statement that brought so much clarity. I don't know why I did not think of that. I have used logic analyzers before and I know that is the case there. Don't know why I would think a scope is somehow maical.

But the alternate mode that Mr. Chips mentioned seems promising.

 

Page 2-35 of the Rigol manual shows the different Trigger Modes. You want Alternate Trigger.
Page 2-42 shows how to use Alternate Trigger Mode.

I gave this a try could not get it to work. I even tried both channels coming from the same source. No matter what I did I could not get a full wave form to display on both channels.

That manual is pretty horrible. If I read it correctly, it says I need to setup the same triggering mode for both channels.

Not that this is all that important. I like the idea of using run / stop in these situations that RB presented. Just that it would be nice to understand how these basic trigger modes work.

 

That must mean that the manual is lying.
Or send the Rigol to me and I'll get it working. Return not guaranteed.

 

That must mean that the manual is lying.

Damm, I hate when that happens. Throws my RYDM right out the window. Read Your Damm Mannual.

 

That must mean that the manual is lying.

No it is just not clear to me. Or just not understanding it correctly.

 

Or send the Rigol to me and I'll get it working. Return not guaranteed.

And I will keep my "broken" scope. Than you,

 

It's really worth getting familiar with all the triggering options.

Mine has what are probably standard trigger functions these days, things like trigger on / or \ edge after XuS. That is fantastic for capturing packets of serial data, because it triggers on the start bit of the first byte.

Or trigger if slope is more/less than Xvolts/sec etc is great for capturing noise defects on a sine like AC mains.

I rarely use digital 'scope as a live display. It's almost always set to trigger and capture now so once it has captured data I can zoom in, scroll back and forth in time, vertically overlay one trace over another etc.

But keep in mind that I still use my old CRT 'scope for a lot of live display stuff.

 

I figured it out. On the Rigol anyway, Alternate throws the time base for both channels WAY out of wack from what it was. In fact it looks like it changes them differently on each channel. I should have noticed that but I will chalk it up to my inexperience with scopes (at least not a lot of experice since I left my Field Technicin job about 32 years ago).

Anyway alernate works, you just need to readjust the horiz. deflection on the Rigol after you switch to it.