EEVblog #1324 - Oscilloscope Reference Waveforms are USEFUL

Dave shows how to use reference waveforms to capture, compare and time correlate more then one signal at a time on your oscilloscope when you just can't hold all those probes at once.

#Oscilloscope #Trick #Tutorial

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[EEVblog]

NOTE: If your trigger reference signal is slow going then that could add some jitter to your time correlation. Also any variability in say RC power on reset time constants etc. Just be wary of that if doing exact measurements.

[MrBrechtD]

Now the trick is to remember this trick when you need it :D

[KarstenBecker]

I really admire the solution for protecting against accidentally touching the big fat capacitor and coils over in the right...

[UpcycleElectronics]

Very useful, especially for a partially disabled guy, like me, fighting shaky hands already.

[BurntTransistor]

You really can't beat Keysight's user interface... so much better than Rigol, etc. in my opinion

[dentakuweb]

I've never used that feature on my 1000X scope. Now I see how it could come in handy.

[EfieldHfield_]

Usefull in all my years i never considered using the reference like that. I always used it for, well a reference, to compare things in future measurments. Never thought of it as an extra pair of hands until now. Thx

[michelfeinstein]

1:00 you need to eat more sushi Dave, practice your chopstick abilities, Asian engineers have a clear advantage here

[keganvisagie]

You are awesome Dave. Your videos are super helpful.

[NilsJakobson]

This is how I ruined a thermal camera trying to find minor noise issues. The probe slipped and I ended up with burnt thermal sensor. $800 loss (which already was great deal) and disappointment for a long time..Giving a big thumbs up for this video, although I do not have a scope with reference waveform memory this indeed is a very good trick that I would not have though of. Thanks Dave as ususal great stuff!

[oswaldjh]

Tight probing may also cause problems if the ground band on the scope probe touches a live heat sink or power transistor package.
Don't ask how I know this :(

[eDoc]

As a user of a conventional analog oscilloscope I clearly can't use the method described here but it is interesting to note how analog scopes internally use the same trick. A conventional scope can only display one beam at a time so two (or more) channels are emulated by drawing a trace of one signal, then one of the other. Since both traces are using the same trigger source the correct time relationships are shown.

[martinandersen]

Smart trick.. when I need to measure several signals, I use my Sensepeek PCBite 2x SP100 Kit 4015

[robertholmes]

The "I'm here all week..." line, just cracked me up! :-)

[WillKalman]

I switched on my Keysight 2000-series scope to check out this feature. I hit the Analyze button and was about to be very disappointed that the feature wasn't in the menu.... until I checked the manual and saw that it has its own button labeled "Ref" (who knew, right?), located on the right side under the Math button.

Thanks for "triggering" the mental refresh on this feature!

[PainterVierax]

This is a weird and paradoxical statement at start since you advise to have a 4 channel scope (that will be inferior in spec than a dual one for the same budget) but you show how to not use those four channels then you show how important it is to have a good memory depth on the device (a thing you can't have on a tight budget especially if you go with a 4 channel scope).
If that was not an ironical line at start, you just prove the opposite of it.

[toxanbi]

I always use this trick, when it's applicable. However, on Rigol DS1000 series the REF waveform does not obey the overall time offset and time scale.

[djjackson]

Just use a helping hand setup. Attach probe to flexible arms and you have 2 free hand.

[Kalvinjj]

One little thing I came up with when using the scope too is to slide the plastic protector of the ground part, if yours can do this, slide it up over the exposed ground ring near the tip, or cover it somehow. If not, it might just short something on your circuit accidentally as well.

[vovetsno]

Thank you, I've learned something new.