FYI
http://www.rexresearch.com/davis/davis.htm

Time (September 25, 1964)

Making Resistors With Math

Brief, high-power pulses of electrical energy throbbing through intricate
circuitry are the heartbeats of modern radar. But they are the bane of many
an electronics engineer. Sometimes the high-frequency currents that are
crammed into a pulse swirl through a simple resistance as if it were also a
small coil (inductance); sometimes the pulses treat the resistance as if it
were a capacitor. Either way, coil or capacitor, those unwanted effects
introduce annoying problems.

In an effort to reduce such side effects, electronics experts have resorted
to all sorts of tricks. But in most cases the best they could do was to
follow advice as old as Scottish physicist Maxwell, the father of electrical
theory, who died in 1879. It was Maxwell who pointed out that resistors can
be bent into hairpin turns so that their current flowed in two directions,
canceling out capacitance or inductance. Later, physicist Georges Chaperon
wound resistances into intertwined coils with the same result.

Wandering Mind ~ 

Those solutions work well, but not quite well enough for today's high-power
equipment. At Sandia Corp. in Albuquerque, physicist Richard L. Davis was
busy trying to devise improvements. One day he let his mind wander and
remembered an old mathematical parlor trick, the Moebius loop (named for
German mathematician August Moebius, 1790-1868). Math suddenly merged with
electronics, and Davis had what he was searching for: the design of a
noninductive Mobius Resistor.

A Mobius loop can be made by cutting a narrow strip of paper and gluing its
ends together after giving the strip a half-turn. The loop that results has
peculiar qualities. Most important, though the paper it is made of has two
sides, the loop itself has only one surface. This can be proved by drawing a
pencil line down the middle of the strip. The pencil line covers both sides
of the paper and returns to the starting point without the strip's being
turned over. When cut along the pencil line, the paper forms not two loops
but one long, narrow loop. Cut once more in the same manner, the narrow loop
becomes two interlocked loops.

Double Passage ~ 

Davis made a Mobius loop out of a strip of nonconducting plastic that had
metal foil bonded to both sides to serve as an electrical resistance. He
attached wired to the foil on opposite sides of the strip. When he sent
electrical pulses through these wires, the current divided, flowed in both
directions through the foil, and passed itself twice. Because of the double
passage, the inductance was as low as Davis had hoped. He is delighted but
still puzzled. The pulses apparently pas right through themselves, and he
cannot be sure how or why his device works. "Maybe Maxwell could tell us",
he says, "but he's dead." 

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