How to measure waves of electricity

Special thanks to my top Patreon supporters!
birdiesnbritts
John Sosa Trustham
Vladimir Shklovsky
Aloysius Sparglepartz
Ryan M
Jason Whatley
Lohann Paterno Coutinho Ferreira
Kasper Nielsen
Jeffrey Mckishen

[ballad]

Finally a YouTuber that actually goes into detail with experimental setup and allows us to conduct our own independent research ❤

[rogiervanetten]

THREE AlphaPhoenix videos in one day?! Christmas came early!

[RobertMilesAI]

I think every experimental research paper should have a video like this, it would make replication a lot easier

[tveilleux]

I love how this video demonstrates that proper experimental design relates to just careful thinking and understanding of assumptions and first principles, and does not have anything to do with how fancy the equipment is. The whole experiment used dead bug circuits and a super cheap scope, but was crafted to be able to gain them necessary insights, and it does so with sufficient resolution to prove the points.

[markedis]

I agree the 3 videos should be a mini series or a really long video on your main channel. Stuff this good shouldn’t be resigned to the second channel

[milos_radovanovic]

For improved accuracy with differential probes, you should have connected the grounds between them!
The second thing, and I think you did do this, but non the less:
It is very important to use the x10 setting on the probe for two reasons: to increase the input impedance of the probes (the thing you tried to do with capacitors), and to enable you to trim the probe's compensating capacitors (little screws on the side) to eliminate ringing.
Trimming is done with a probe attached to the test generator contacts just beneath the display in the middle of your scope.

The problem you saw with the probe disrupting the signal patterns is from the ground connection of the trigger probe attached to the switching circuit.
You really should have added some proper analogue switchings to the circuit, like SN74AC66, and also separate batteries for the oscillator and the driving the line, to mitigate ground coupling through the scope.

[Daniel_Anishchenko]

This was really cool, please make more EE content. 90% of ECE content on youtube doesnt go past first 2 weeks of Electronics 1 so its really cool to see some applied signals content.

[vaarst]

When I watched the main video I thought, wow, he must've had a shitload of probes to take all these measurements at once.
It never occurred to me that you just took a shitload of measurements with three probes.

Thank you for your hard work!

[AnanayGarg]

Itis scary how much work and thought went into this. Crazy inspiring work.
Would love to see how you animated the electron motion according to the observed experimental voltages.

[garci]

All 3 vudeos wefe just amazing!! Seriously!

I would make two minor changes though. For the Schmidt trigger, add a couple.of 0.1uF or even 10nF capacitors.ij parallel to the large ones you have. As close to the vcc/gnd pins of the chip as possible. Rhe big capacitors help but their internal resistance and inductance means that they are "slow". So for the very fast transients you want a fast 0.1uF capacitor bormally known as a "decoupling capacitor". This will give you much better rise times

Swcond improvement would be to use a differential probe inatead of the math function. Thia way you sont have to worry about the disconnected ground leads and the inductance that those leads (pf the red and black probes) create. Remwbwr that all ground ports of the scope are common ao you have a "back" path or at least aome potential interference from the ground leads hanging around.

A differential probe does the math in analog way nect to the measuremen point and ahould give you wven better noise immunity (although the traces did look very goos)

Finally, given you hace a "repeatable" trace.. if you apace put the pulaea enough (say at 10khz) you can use the averaging funxtion of the scope to get better dynamic range /.noise performance by accumulating hundreds of runs of the same repetaed event.

Some scopres (sampling scopes9 can evwn increas the time resolution by adding a slight jitter to the trigger and getvsamples at slightly different times but due to the repetitive bature of the signal, tgey can build a higher resolution (time wise) "Image"


Finally ypu can use the trigger input od the svope instead of one of the channels, directly from the Schmidt trigger output (maybe uaing one of the channelse separately). That way you can sanple using channels 1 and 3 and thus run the scope at dohble the rate. For example of the scipe is 1gigasample/s that usually applies to channels 1 and 3 by themselves. But if you capture all 4 channels.or 1 and 2 (or 3 and 4) then the rate goes down to 500 megasamples per channel

[Gefionius]

Love your posting of the extra stuff and outcuts here! Thank you for all the hard work!

[dennyoconnor]

The twisted pair is a transmission line. Your rapidly switched pulse is a mix of RF (wide band) and DC. We need to be careful and not equate the DC bulk Resistance of the twisted pair to DC flow, with the Impedance of the twisted pair to an RF wave front. Different critters. The pulse that is impressed and propagated at the velocity factor of the transmission line when the switch fires each time, is primarily a radio wave that rides up on the skin depth of the wire (frequency dependent) and its propagation along the wire is resisted by a combination of reactance and surface resistance, that we call impedance. Along with that is the DC current that is more controlled by resistance and propagates through the bulk of the metal at a different velocity.
This can be shown by a long balanced line made of two, very thin wall, hollow copper pipes. Measure the DC resistance of the line, then measure the impedance and velocity factor of the line at some arbitrary, but stable, radio frequency.
Now, replace the hollow pipe with solid round bar of the same diameter and repeat the measurements. The DC resistance change will be significant while the velocity factor of the balanced line to the pulse will remain close to the original.

[stefansynths]

2:49 My EE background says for smoothest power you want a combination of different capacitors. I would use a 10uF electrolytic, a 100nF MLCC, and a 1nF ceramic in parallel.

Each capacitor is most effective in a certain frequency range due to parasitic resistance and inductance. By combining different types and values you can cover the whole frequency range of interest.

[timoleppanen]

Brian, this is probably the most interesting series of videos I’ve ever seen. No hyperbole here. So many levels of fundamental understanding about electricity, impedance, metrology, being shown and explained in an intuitive way.
One question I was left with: how does current depict itself in the top graph of voltage? Is it the increased area under the curve? The slope of the wave front? I know charge has to flow to change the voltage within the line, but I’m having trouble connecting it to the measured values.
Thanks.

[nosy-cat]

This project is a masterpiece. Well done. Thanks for showing the setup as well, this answered all my questions, along with all the questions I didn't ask but should have

[Featherbeans]

Your youtube channel(s) helped me understand more about electricity and it's properties more than any other content on this platform. Thank you! ❤

[drfrancintosh]

AlphaPhoenix: "We take thousands of measurements so you don't have to." Mind blowing project. Amazing attention to detail. And a result that changed my understanding of electricity. I'm subscribing... and continued success!

[MeriaDuck]

20:45 "And it's just that easy" is quite the statement! That is a LOT of painstaking work with many mistakes that can be made. Very impressive research and so cool that a reasonable digital oscilloscope can capture this.

[GrandNebSmada]

These three videos have been the most fantastic learning experience I have had in a very long time. I have for years always wondered about this exact same thing and now I feel like a window has been put in a place where there was once a wall. Thank you so much for your work!!!

[theangel]

You deserve a Nobel price just for this video, really !