Re: Multilayer Oudine coil

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Dr. Duncan Cadd by way of Terry Fritz <twftesla-at-uswest-dot-net>" <dunckx-at-freeuk-dot-com>

Hi Vladi!

<snip>

>But the old article that frequently appear on list extract from an
old
>Scientific American rewiew known as "An inexpensive X ray machine"
tell
>of a coil called Oudin, excited only by 120vac mains with a kick coil
to
>interrupt the current and closing to generate primary oscillations,
and
>connected primary-secondary coil, air core,tilayer but the strange
fact
>is that the secondary is a multilayer coil of 5000 turns on several
>layer (tesla coil are only single layer secondary, if not will be an
>enormous burning) and I'm not sure that the primary and the secondary
>resonant frequencies are tuned (primary capacitor 1uF).
>Someone knows other circuits like this?


In "High Frequency Apparatus" by Thomas Stanley Curtis, via
http://www.lindsaybks-dot-com (I don't know if he still has any of these,
or if they've sold out) there is exactly the circuit you describe.  It
is powered by a kick coil which can be fed from either mains or
battery and is claimed to give up to seven inch / eighteen centimetre
sparks.  The secondary is also as you describe, a multi-layer coil of
pancake form, and to prevent flashover the whole thing is potted in an
insulating compound rather than being air cored.  The windings are
tuned, and a multiplate primary capacitor is provided in order to find
resonance.

Dunckx