Unless somebody beats me to it, I’ll bring in my label machine and mark’em…
If you forget your label maker, the Space has one or two floating around. I saw one in Electronics a few days ago.
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…or you could laser engrave the plastic housing 
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Good grounding in these readings, but I hadn’t yet tweaked the probe compensation. These readings don’t show up in the slower cycles, but the screenshot I posted was for one of the faster cycles. I haven’t returned to that measurement since I adjusted the probe. Thank you for the tip. I was a little too eager to get a reading, and it worked, but I wondered about the funny plot.
I never did get a perfect square. As I get a tight corner on the rising edge, the falling edge gets out of whack. But I suspect I’m just using an expanded time scale compared with what might be normal for this procedure.
I’m really grateful for the “hair pulling” topics.
My first impression is that they were presented too early in an intro class. And I still think they might be, that we need a few more guided examples, and a set of steps to cement some usage … Something like:
First, setup the scope for the task. For our task, we’re doing X so set for t’d, dc, 10x probes and reset ground, set voltage range for both probes to 2v.
Then attach the ground, and set the probes. Then you see the signal way off the top and bottom of the scope? Narrow the signal into the vertical space of the scope. Then adjust the time scale so you can see a full cycle on the screen.
Now, using (some procedure I haven’t figured out yet, reliably) get the signal to stop moving separately from the visual reference window of the screen.
In an additional class, I think we should have a series of screenshots of a signal, and the class needs to decide what setting is “wrong” and requires adjustment.
I’m working my way through the manual, so I’m sure I’ll catch up with the issues I’m heaving on my learning curve pre-RT(fine)M, but another issue I’m looking to understand is:
- why the automode often, but not always, zooms in the voltage scale down to the millivolts, when it other times zooms to 1-2v (and is successful there)
- why auto seems to work best/works only on probe 1, and always enables 1,2 and 4 even when I have nothing attached to 4 (or 2)
- how to auto on a probe other than 1
These are shared more for a sample case in one persons learning curve, it’s hard to know what any individual will be puzzled by when you’ve been doing this for years.
A general framework of steps used to manually fix a signal I think would be a helpful reference. Auto modes aside, it’s clearly not suitable outside of a range of situations, and a reference set of steps might also help reduce hair pulling.
I’m absolutely in for more classes. Let me know how I can help. I can bring problems, issues, ideas, questions, gear or beer.
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Thanks for the excellent feedback! All valid and greatly appreciated comments! That was literaly the first try for that course - it wasn’t quite clear what to expect. However, there are some good ideas now based on your feedback in this thread, and the real time feedback from class.
Probably some of what you’re seeing wrt square (or not) edges is real, some of it probably is not. That’s often an issue (is it real or not), and forces sketching out the “circuit under test”, and considering how the additional connections added by the probe could affect the measurement.
The signal ‘walking across the screen’, or ‘moving separately from the screen window’, is usually a function of the “trigger”, or sometimes the signal you’re looking at actually does change around a lot. Or in the case of the Tektronix TDS scope at the space, it’s because the trigger function ist kaput.
You’re definitely in a productive direction with the checklist approach you describe. You’ll surely find & measure signals much more quickly with a checklist like:
- what kind of signal do I expect to find
- what basic probe scale, voltage scale, coupling mode, timebase setting and trigger mode make sense
2b. other settings refinements like bandwidth limits, persistance, etc… - check that probe is calibrated
- check that display is triggering on a ‘known signal’
- measuring away…
One idea for courses is to have regular (maybe every other week or every week?) workshops. The first part would be perhaps 20 or 30 minutes of classroom style training, the remaining hour or so would be to help people make measurements or troubleshoot their own projects. The thought is that such a format would shorten the distance from lecture to hands-on, and focus on real problems versus more abstract examples. Also to spread it out versus trying to cover too much in a single sitting.
For example, the first few sessions might include:
- Grounding
- Measurement Checklist
- Triggering
- Acquisition modes
What do you think about such a format?
It seems like a format such as what you’re describing might be best supported by a relocation away from the lecture style room to the lab styled room, with work space and power. This would allow students who had a project and/or a scope to bring them in, and follow along. It would allow for those who did not to watch the actual knobs get adjusted… it’s my impression that many scopes have the same basic layout, so even just seeing where someone’s hands are while the screen changes would be helpful.
Had a chance to use the new toy tonight while helping to debug an arduino with motor shield. Sure is nice to be able to view 4 channels at the same time 
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I labeled each of the probes so they can hopefully stay with the Rigol, or at least get reattached to the Rigol if they migrate.
Unfortunately, I found one issue. Probe #3 has what appears to be a mechanical manufacturing defect. It works fine when the clampy tip is attached. But the probing tip gets stuck in the clampy tip when you pull it off - vis-a-vis:
Maybe somebody who knows these specific models can check it out. Otherwise, I’d suggest exchanging probe 3 for a new one…