Oudin Coil Design

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Original poster: "Angelini, Frank J" <FrankJAngelini@xxxxxxxxx>


I am trying to duplicate a very old (horizontal) design Tesla coil, 
which was featured in "High Frequency Apparatus" by Thomas Stanley 
Curtis, 1916.  This was referred to as a Tesla coil because the 
primary and secondary windings are in a horizontal 
orientation.  while what we would normally describe as a Tesla Coil 
(vertical form) was referred to as an Oudin Coil.  The coil used a 
constructed  HV transformer rated 5000 volts, 100 ma. 3 glass plate 
caps connected in parallel for a total of .03 mfd and straight static 
gap.  Each half of the primary consists of 4 turns of edge-wound 
1/2-inch copper bar, 7-1/2 inch in ID.   Each secondary is 6-inches 
in diameter, 8-inches long, with 400 turns of #30 DCC copper wire.

Question:   The author does not stipulate if the primaries and 
secondaries are wound in-phase or out of phase.  In other words if 
the right-hand primary and secondary are wound clock-wise, should the 
left-hand coils be wound counter-clock-wise?

How can I duplicate an edge-wound primary.  Is some special jig or 
fixture required?  Can this be done in a home shop?

An optional Telefunken quenched gap is suggested.  This used copper 
disks separated by mica washers approx. 6 inches OD and 4-1/2 inches ID.

Can some one suggest a source of these washers?  Is there a modern 
substitute for mica?

Thanks,

FJA