

Right angle circuitry - yread
http://amasci.com/elect/mcoils.html

======
tricky
semi-related. People who build tube guitar amps (lots of high voltage AC) take
component placement very seriously. The magnetic fields floating around the
chassis greatly affect tone (and noise, which is sometimes a big part of
tone.)

Some of the high end amp builders I know have spent a lifetime of
experimentation figuring out the best way to place components and route
circuits [anecdote, no references available]

If you want a simple example, have a look inside any audio amplifier. The two
transformers will always be mounted at a 90 degree angle to each other (power
xformer/output xformer) to minimize noise.

~~~
aarongough
Yes indeed. I have actually built a few tube guitar amps for fun. I did the
designs myself and the first one produced so much noise/hum that it was
practically unusable.

Twisted pair wiring, careful routing of grounds, transformer location and
component selection all seem to play massive roles.

No wonder then that most amps these days are built around transistors, even
though they sounds worse...

------
mmagin
"James Clerk Maxwell might be spinning in his grave. But is he rotating around
his long axis, or flipping endwise?!!!"

~~~
rikthevik
Only the right hand rule can tell us that.

------
jacobolus
I assume you got the link from Randall’s blog, yread? I probably should have
submitted it here when I came across it a couple months ago and emailed the
link around to “nerd snipe” various physicist/engineer type friends. Either
way, I’m glad to see this get some discussion on Hacker News.

The author’s (William Beaty) other pages about electricity are somewhat
interesting too <http://amasci.com/ele-edu.html>. In particular, he has some
good rants about the terminology/pedagogy of E&M/electrical engineering:
<http://amasci.com/miscon/elect.html> <http://amasci.com/miscon/elteach.html>
<http://amasci.com/miscon/whyhard1.html>

In short: the terminology as used is ambiguous and confusing, and the common
metaphors used to explain electricity are somewhere between misleading and
wrong, and this has resulted in most people, including most textbook authors,
having a poor understanding of how it actually works.

------
pixelbath
Is it bad that this is the first time a toroidal transformer has been
explained to me this clearly?

------
networkjester
Does anyone have an answer or idea for the "WHY?!!!" part of Figure 8's
paragraph?

~~~
jackdawjack
in figure 7, Faradays Law: changing magnetic field in the left torus induces a
variable current in the wire, then via ampere's law the changing current in
the wire induces a magnetic field in the second torus.

However in figure 8 while there is an A field which extends to infinity, don't
forget that B = curl(A) and so the magnetic field of the torus is going to be
confined within it. As such there's no way to induce a new field in the
additional torus. A is a potential, it's not a "real" field in as much as you
can only measure things like |B| and |E| (or quantum phases induced by A in
the Ahranovov-Bohm experiment)

~~~
networkjester
Thank you. That was a nice, concise answer! (it's been a while since I've had
any E/M)

