Primary Coil Wire, more...
To: mail11:;-at-cimcad.enet.dec-dot-com (-at-teslatech)
Subject: Primary Coil Wire, more...
From: I am the NRA <pierson-at-cimcad.enet.dec-dot-com>
Date: Thu, 26 Jan 95 11:18:47 EST
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>Subject: RE: TESLA COIL DESIGN
>Also, am I correct in assuming that all the wires in the primary circuit should
>be able to carry at least as much current as the primary winding?
Not neccessarily. Unless I am MUCH confused. Richard Qm, check me on
>I always hear about "heavy" wire, but it doesn't make sense
It dies, but there is a subtlety:
>to use beefy tubing in the primary coil if most of the wire in the primary
>circuit is any smaller (higher resistance).
The tank (any tank) can/does have high circulating currents, resonant
currents, that are (hopefully) higher than those in the supply wiring.
With the currents involved (mA range) the risk of melting the wire is
low, even with resonant effects, however the losses are significant
if the wire is smaller. Effectively, the current is deliverd to the
primary tank in small doses and "Accumulated" there. Its not
(conventional mode kicks in here) "free" or "found" current. Its just
"stored" over a period of time. Also, regardless of current limits,
reducing the resistance improves the Q. And using larger wire
reduces the HF losses due to the curretn riding mostly on the surface.
One could argue for all (tesla) primary wiring to be tube, to get the
best results. flat ribbon conductor (ground strap style) should also
have advantages here. (They are used in high energy/fast power
circuits, in preference to "round" wire.) I cannot say whether the
gain would be enough to justify their use.
I will Find time, i will...
Sweeping them for esonance is a good thing. A sparkgap has a broad
range excitation. If a cap (or any other part) has a resonance
available in that range it can/will (non rigourous) pull energy away
from the rest of the apparatus. This:
Keeps it from the main purpose (HV, or transmission here)
can lead to overhat/"rapid dissaembly" of cap.
The sweeping suggestion is a good one, i have done that, for other
puposes and with other equipment.
At the risk of teasing, the scheme i was reading of would be useful for
evaluating an unknown cap, before building in. It uses a scope in an
x-y mode, one deflection voltage, one current. Ideal cap presents
a straight line. Lossy cap presents an ellipse. (Thats enuf for
some, more as i get a chance.)
Off the backlog:
Someone was commenting on the effects of "arcs" on Telsa Power
Transmission: Its not at all clear that the "lightning" effects
would have been present on an operating system. It can be argued that
NT was overdriving the system, with the lighting as a "voltmeter". (I
remain unconvinced on the practicality of the system, but for other
Also, an arc/spark (not the same thing, but lumped here) are not
as lossy as one might think. An Arc (and, to some extent, a spark)
in a real sense, have negative resistance. When an arc is struck in air
the voltage "across" it (once struck) is quite low, so the losses are