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Newborn coil - will be twins (fwd)





---------- Forwarded message ----------
Date: Wed, 26 Feb 1997 18:13:50 -0500
From: "Robert W. Stephens" <rwstephens-at-headwaters-dot-com>
To: tesla-at-pupman-dot-com
Subject: Newborn coil - will be twins

All,

I am now getting around to fabricating my first tandem T.C. system.  
The one I am building is for my proposed electrical theatre show.  I 
am building this unit quite compact with hopes to deliver maximum streamer 
length in a limited space, especially a  limited ceiling height environment.
A minimum design goal is to achieve 12 foot connecting streamers 
between two coil towers which themselves are only 4-1/2 to 5 feet 
tall, operated underneath a 10 foot ceiling height.  From such a 
short tower I expect significant floor striking activity.  Gotta have 
those ground strikes, right?! : )

I have selected 10.5 inch O.D., 5/16ths inch wall PVC drain pipe on 
which to wind these coils as I had some on hand.  They will be 
closewound to a length of 36 inches with #18 AWG formvar copper 
magnet wire.  The resulting aspect ratio of 3.4:1 should easily achieve
the minimum requirement of 2X resonator length in output streamers.
Calculated L on these coils is 50 mH.  Turns count will be in the 
order of 860 turns, but I'm not counting (that calculation was made 
ONLY to determine how much wire to buy, about 12 lbs per coil).

The secondaries will both be wound in identical sense.  The flat 
spiral primaries will be opposites (mirror images) of each other to 
facilitate symmetrical connection to the 3/4 inch copper pipe 
parallel transmission line running between the two towers.  Thusly 
the desired 180 degree phase difference atop the two towers will be 
achieved.

I plan to kluge it together employing a rotary break, capacitor and 
transformer borrowed from another system in order to speed up the 
evaluation process of system capability, and better determine actual power 
requirements of the completed system in its destined venue.  A proper 
sized power supply will then be constructed.

If I am as lucky with this system as I have been in the past with 
single tower classical systems, then this system should really cook.

I will keep y'all posted of results as available and will eventually 
post photos on funet.

Cheers,
rwstephens