Is it really the scariest chart in electrical engineering? Maybe not.
It's scary, but it's also damn useful.
I think there are 2 reasons that engineers find the Smith Chart intimidating. The first is simple. People learn Cartesean Coordinates in middle school. They get exposed to just enough of the Polar Coordinate system to hate it, and not enough to know when it is useful. So in the end, they don't like anything that doesn't look like a standard X-Y plane.
The second reason is that the chart itself is based on Imaginary numbers (the Square root of -1), and they don't trust the math enough to just use it. even though it has been shown to work.
This is the Veritasium video The Scariest Chart in Electrical Engineering
Well, and a fair number of the charts do say "Black Magic Design" on the chart itself. It does simplify certain calculations around antenna design; that can seem magical.
We've verified that this crazy map switch from the complex plane to the reflection coefficient plane leading to these insane appearing circles, they actually mean something. Like, in real life we've used it to increase the power. Crazy. It is crazy.
I first encountered the Smith Chart in college, and later when I was getting/upgrading my Ham radio license. The video is long, at 40 minutes, but I enjoyed it.
I've been offered that video many times but never watched it, because as an RF design engineer, Smith charts are almost a second language. I started learning to use them back in the '80s, and don't really remember being afraid of them, just being defeated by them (notice I didn't say "beaten by" them). And, yes, I use one of those handheld vector network analyzers that display on a Smith chart whenever I'm checking an antenna.
ReplyDeleteIf you want a PC Smith Chart, see SimSmith by AE6TY. I use it all the time. I still have a stack of blank Smith charts I rescued from the garbage bin back around 1995. The paper, with both impedance and admittance on one sheet, impedance in red with admittance in green, is a beautiful thing.
Since you're saying the video is good, I should watch that.
Sorry it took me so long to approve that comment... Google/Blogger/Alphabet has been giving me fits...
DeleteI'm not sure you would find the video of interest, given your knowledge of the Smith Chart. I like Veritasium videos in general, and I haven't used the Smith Chart much, so this is still fascinating.
I happened to come by around 11:30. No big deal on not putting up the comment. I think everyone on Blogger has troubles with it at some point.
DeleteI thought the video had it's good and not-so-good sides - which is probably true for every video lesson ever. They made it a little harder on themselves by not talking plainly about the behavior of a transmission line putting all possible values, from zero to infinity, on the outer diameter circle. As you might know, I've done many posts on the Smith chart over the years, but none quite so focused on the world Phillip Smith was living in and the history they emphasized.