h a l f b a k e r y
Cogito, ergo sumthin'
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If my experience with biological science has taught me
anything* it's that you must embrace complexity.
Conversely, my brushes with the world of electronics
demonstrate that they have quite enough complexity
thankyouverymuch and if they wanted ambiguity then
they'd have done an arts degree.
is this more apparent than in circuit designs.
There's a symbol for each type of component, and usually,
a value or two attached to that symbol. The symbol is
what, the value is how much. -/\/\- 100k. A resistor that
does 100 kOhm worth of resisting. Lovely, simple, logical
organized. Circuit layouts are 2D with lots of straight lines,
you can trace where everything goes and easily represent
it on paper or a screen. It all has a calming sense of order.
Components have a purity of purpose and the engineer can
simply arrange them to achieve the desired result. It works
very well, but it's wrong.
A peek under the petticoats of electronics reveals sordid
secrets. Complexity and messiness that the greybeard
engineers talk about in hushed tones. Those 2D circuit
designs aren't very good, the components would be more
efficiently arranged in 3D space. At the small scale, it gets
worse. A diode in a microchip is a really crap diode.
Resistors resist, but they're not 100 kOhm when
manufactured, they're a distribution around 100 kOhm.
Even the simple wire isn't. Represented by a line, it's pure,
a conductor. In reality, it's a conductor, and a resistor, and
a capacitor and an inductor. It's amazing anything works at
So, instead of fighting the futile fight, we can embrace the
opportunities. I've recently been dabbling with an
electronic motor controller. It is sensitive to voltage drops
when the battery can't keep up with demand. To solve
this, a bank of capacitors sits at the controller end of the
battery connection to act as a short term power supply
buffer. This is a feature universal to almost anything with a
DC power supply and fluctuating DC demand, which is a lot
of things. Instead of using wire/cables optimized for low
capacitance and then adding capacitors at the end, how
about optimizing the cable FOR capacitance.
A capacitor can be made by taking two thin foil-like
conductors separated by the thinnest insulator possible and
then rolling them up together. To make a capacitative
cable, you can simply extend this idea lengthwise and have
terminals at both ends. Cable capacitance will be
proportional to length. The cable can be cut to length and
then the two conductors teased apart and soldered
appropriately, a little like a coaxial cable.
Now, if you have power-hungry components, like a
MOSFET, or a sub-component like an HDD in a computer,
the supply will be inherently smoothed.
*Graphs are made from grant money via salty water.
Similar thought but compressed slices.
Designing the perfect electron path for use. [wjt, Feb 16 2019]
A circuit made from a single wire. [Wrongfellow, Feb 17 2019]
||Before the invention of coaxial cable, and before impedance matching was understood, there were a few attempts at building a maximally capacitive (and minimally inductive) cable. They didn't catch on.
||Practically speaking, most of the time adding capacitance to the input side of a circuit is balanced against inrush current, especially in the world of plug-and-play devices, and often the inductance of the cable before the caps is advantageous.
||Nifty. I once thought about how, "Even the simple wire isn't. Represented by a line, it's pure, a conductor. In reality, it's a conductor, and a resistor, and a capacitor and an inductor." and if it is bare, possibly a semiconductive oxide layer.
||I wondered if you could build a circuit with a resistor and an inductor from one wire, perhaps with a Y shape at one end doing capacitance, and make a pulsed waveform from just a length of screen-door-spring looking wire with a Y on the end or at branches.
||It is different than capacitive wire, but somewhere on here there might be an idea I had about making circuit board traces out of  hollow square wires that function like waveguides with the idea of reducing EM interference at corners or through-holes. I have no idea if it would have worked.
||""It works very well, but it's wrong.""
||Won't the layers buckle if you bend it with any reasonable
||//I wondered if you could build a circuit with a resistor and
an inductor from one wire, perhaps with a Y shape at one
end doing capacitance, and make a pulsed waveform from
just a length of screen-door-spring looking wire with a Y on
the end or at branches.//
||This is actually quite common. [link]
||//Won't the layers buckle if you bend it with any reasonable
||You could make it like ribbon cable, you could make sub-
conductors, like a fine stranded wire with a core and an
outside insulated from one another. There are a few ways,
all very doable.