Re - spec for my coil - comments please

To: tesla-at-pupman-dot-com
Subject: Re - spec for my coil - comments please
From: guy wilson <wilson-at-vossnet.de> (by way of Terry Fritz <twf-at-verinet-dot-com>)
Date: Tue, 08 Dec 1998 17:20:32 -0700
Approved: twf-at-verinet-dot-com
Dear All

I have tried to give a full spec of the coil which I plan to build. This
will be
my first coil. I have 3 caps which were in an electrostatic air cleaner and
are
rather small (about 1,5 inch diameter and 2,5 inches long). I also have a
problem
at the moment tripping the circuit breaker here when I switch on the variac
-even
with no load on it.

I would welcome any comments on the suitability of any part of the system
and what
I might expect to get out of this design.

The calculated values are from Ed Sondermanns program as "improved" by
Corey Ruch
and from R Scott Coppersmith's "Wintesla" - many thanks.

They must be Absolutely Potty

Guy Wilson



Design Parameters - Guy's (first) Tesla Coil

Line Filter , Line side of Variac     10A Siems commercial EMI Filter
Fuse                                  15A, slow blow
Variac                                5(10A) - need help with surge
supression -
trip switch
Transformer                           Oil Burner 10kV 20mA
Kickback Choke                        2 x 50 turns on 2 inch (50mm)
diameter pe
pipe
Safety gap                           three ball bearings,middle movable and
grounded
Safety caps                           pass -i don't have any suitable now


Primary inner diameter              2,0 inch (50,8 mm)
Wire Diameter                       0,079 inch (2,0 mm)
Wire spacing                       0,2 inch (5 mm)
Total turns                        9, tapped at ca. 5,6 for res. Frequency of
235kHz
Inductance                            0,016mH, 0,006mH at 5,65 turn tap
Caps                                 3 x 0,022uF film caps in series, rated
6000v
DC (and fingers crossed) Should give around 0,07uF - matched to transformer
Spark Gap                        RQ type or flat hard copper pipe, six gaps
of ca.
1mm (0,04                             inch)


Secondary
Coil Form   Plastic pipe 2 inch OD x 20 inch long
Winding length   14 inches
Wire gauge    33 (0,18mm) - a bit thin, but it's what I've got
Turns per inch   ca. 133
Wire length    ca. 950 ft    (quarter wavelength would be 1046 feet)
H/D Aspect Ratio  7,00
Inductance   22,16mH
Medhurst K   1,00 (does this mean something?)
Self C    5,08pf
Top Load   Toroid, alu duct, 4 inch D x 14 inch outer diameter
Top Load C   15,6 pf
Res Freq. With top load  235khz

I also have the following transformers which could be used with the system -
6600v -at- 30mA neon, centre tapped
8000v -at- 34mA OBI,no centre tap
10.000v -at- 20mA series to give 40mA
7500v -at- >100mA Neon (Rated is 75mA, shorted with shunts removed gives 120mA)