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Hi All,
Working on a test rig design long story short a stepper motor is behaving in a true  way. The current draw is all over the place, it will not move! stick a scope probe on the ![Elephant | [mastadon]](https://www.codeproject.com/script/Forums/Images/elephant.gif) starts moving take the probe off stops, try pressing down (could be a faulty board) no, try another item, no; go back to scope probe Yes! It can't be RF, probe works grounded or not.  Proper Weird!
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maybe the stepper has an intermittent short in it. sounds faulty in any case. The current draw should be stable under a constant load.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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That was my first thought. Changed motors still does it, changed 4988 driver (could have been a fault) still does it but only with a scope probe, not multimeter or other implement only a scope probe (connected to a scope, not even selected channel, but connected).
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Wow. It almost sounds like maybe your scope is doing something to the signal. Could it be your scope is to blame?
ETA: My Salae was acting really strange one day, and I spent all day debugging because I couldn't figure out why my SPI signal was so off. It's still a mystery as the analyzer hasn't acted up since.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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Don't really think so, a cheapo R&S Pro branded UniT model, about 700mV on the probe...
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Inductor or capacitor - I forget which.
I had a similar problem 20+ years ago: the board was working really weirdly so I stuck a scope on to look at what was happening and ... the problem went away. I talked it over with Tektronix, and (apart from their first suggestion which was "ship a scope with each unit?") they were very helpful. IIRC, it was the scope probe capacitance that was fixing it and adding a couple of pF to the line smoothed it all out and it worked faultlessly from then on (though it may have been a small inductor we needed to add, I can't remember and the H/W designer died a few years ago.)
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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I have been thinking that, I just try resoldering the connections to the module. Stupid thing is must be the capacitance as adding other probes or a screw driver doesn't do it (inductive, I think). It happens if I change the motor, the driver board.
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Ground through the scope? The ring of the probe BNC connector is connected to earth.
I'm skeptical of the tiny (pF) capacitance of a scope probe "fixing" this, though it's not out of the realm of possibility depending on what you're connected to.
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Strengthen Aldi - no Tesco struggles! (11)
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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Consolidate
Good getting two supermarkets in 
In a closed society where everybody's guilty, the only crime is getting caught. In a world of thieves, the only final sin is stupidity. - Hunter S Thompson - RIP
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You are up tomorrow!
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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Damn it, just saw that I am longer member at Codeproject than some of my work colleagues are alive. 
Does that make me feel old? Nope. Am having fun with that.
How many are members here since 20+ years and still active?
forging iron and new ideas
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A mere 16 years 7 months for me 
In a closed society where everybody's guilty, the only crime is getting caught. In a world of thieves, the only final sin is stupidity. - Hunter S Thompson - RIP
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14 years here - but it doesn't feel like it at all! Doesn't time fly when you are having fun?
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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I will hit 20* years this December. I first discovered CodeProject at work and it certainly helped with many issues that I worked on back then.
*I had been using it for a few years before I created an account.
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Definitely, although in the last few years it feels somehow overwhelming. So many new areas and technologies added. Stuff that one only hears about but never uses.
forging iron and new ideas
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Agree, I look at some stuff now and it doesn't make much sense to me. I remember spending a weekend learning C from K&R, so I could start a new project the following week. Now it takes me as long as I spent on that project to learn any new language (or even some features).
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Since I started heavily back into C++, moving from C# as a primary I've been so lost in learning the nooks and crannies that I don't have time for other languages.
The blessing and curse of C++ is that it takes more than a single lifetime to master.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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honey the codewitch wrote: The blessing and curse of C++ is that it takes more than a single lifetime to master.
Mainly because they keep "improving" it. 
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Haha, i think even with just C++17 you're looking at more than a lifetime.
The problem is not in mastery of the syntax and core functionality, but in how to apply it. There is so much magic in the application of C++ fundamentals to do amazing things that there are rabbit holes everywhere. It sometimes seems endless. template alone contains worlds.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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19 years, 1 month ...
Graeme
"I fear not the man who has practiced ten thousand kicks one time, but I fear the man that has practiced one kick ten thousand times!" - Bruce Lee
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20 years this November.
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
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I think I may have been? But I lost my original account at some point I think during a codeproject upgrade, or maybe I just locked myself out of it.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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Nahhh, never. You are not even that old yet. 
forging iron and new ideas
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I've been coding since 1986. Offa my lawn. 
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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