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Re: TESLAC spit this out



Tesla List wrote:
> 
> Subscriber: randyl-at-ronan-dot-net Sun Jan 26 13:32:44 1997
> Date: Sun, 26 Jan 1997 00:55:22 -0600
> From: Nathan Lamphere <randyl-at-ronan-dot-net>
> To: tesla-at-pupman-dot-com
> Subject: TESLAC spit this out
> 
> Hello all
> 
> I just got my first x-former yesterday.  It is an actown outputting 9000
> v-at-30ma.  Simply had to repace the pull switch and now it works great.
> 
> I downloaded Teslac and have been trying to figure out what I needed to
> build a TC.
> 
> Here is what I came up using Teslac:
> 
> First of all I have a actown neon x-former with secondaries rated for
> 9000 volts -at- 30 ma.  Yeah, at least now I have the transformer:)
> 
> 1)  For the capacitor if I use two 14" X 14" (overlap measurement) flat
> plates seperated by a sheet of mica (I have not seen how difficult this
> is going to be to get yet), I can get a rating of 56KV with a .04 in.
> thickness.  Does this seem right?

Mica is not generally available in large sheets. Reconstituted mica
(ground up and made into a flexible paper-like material) is also not
usually available in large sheet sizes, and even if it was would not
give you the large breakdown voltage you need, and will be rather lossy.
Glass plates would be more available, or better yet a rolled LDPE
capacitor (see the funet site for constructiono details). You'll need
about 0.01 uF for this coil (using the values of primary inductance and
desired secondary/toroid frequency below).

 The funet site is at: ftp://nic.funet.fi/pub/sci/electrical/tesla/
 
> 
> 2)  For the secondary I (and yes, randomly chose) chose a height of 20
> inches, 6 inch diameter coil wound with 20 gauge wire.  I plan on doing
> this on pvc-type pipe. This is what I was given for calculations:
> 
> The number of turns is: 588.2353 closewound with .034 inch dia. wire
> Secondary winding length is 20 inches
> Secondary winding diameter is 6 inches
> Rsonant freq. is approx. 423.5564 KHZ.
> The required wire length is 923.5294 feet
> The aspect ratio (H/D) is 3.333333
> Reactance is 36491.33 ohms at 423.5564 KHZ.
> The maximun unloaded Q is 146.6225 at 423.5564 KHZ.
> The secondary inductance is approx. 13.71888 MILLIHENRY
> The estimated loaded Q will be approx. 65.16554
> The terminal capapticance should be large enough to
> cause the resonant freq. to drop to approx. 296.4895 KHZ.
> 
> 3)  For the static gap, TESLAC asked for how many volts my transformer
> is rated for and here is the response it gave:
> 
> WHAT IS YOUR TRANSFORMER R.M.S. SECONDARY VOLTAGE
> ? 9000
> THIS SERIES GAP SYSTEM SHOULD BE BUILT WITH  8.0 GAPS
> EACH GAP SHOULD BE SET AT APPROX. .025 INCH
> 
> AND COOLED BY AN AIR BLAST AT POWER LEVELS ABOVE 1 KILOWATT
> 
> What does it mean to have 8.0 gaps?  How does a person go about making a
> gap or if I need 8 of them, how do I make that?

Richard Quick developed a spark gap which uses multiple segments of
copper pipe housed within a 6" diameter PVC pipe, cooled by a boxer fan.
By breaking up the gap into a number of "pieces", the gap can be rapidly
extinguished ("quenched") to get better coil performance. Check out the
funet site for more details on this type of gap as well as an air-blast
gap. 
> 
> 4)This takes me to the primary coil.  I decided to figure it out using
> 3/8" copper tubing, with spacing 3/8" turn spacing and 2 inches between
> the secondary and the primary.
> 
> Here is the response for it:
> 
> YOU NEED  45.7 U.H. TO RESONATE AT 296.4895
> KHZ.
> THE INDUCTANCE AT TURN NUMBER 3 IS APPROX.   4.7
> U.H.
> THE INDUCTANCE AT TURN NUMBER 4 IS APPROX.   8.0
> U.H.
> THE INDUCTANCE AT TURN NUMBER 5 IS APPROX.  12.3
> U.H.
> THE INDUCTANCE AT TURN NUMBER 6 IS APPROX.  17.6
> U.H.
> THE INDUCTANCE AT TURN NUMBER 7 IS APPROX.  24.0
> U.H.
> THE INDUCTANCE AT TURN NUMBER 8 IS APPROX.  31.4
> U.H.
> THE INDUCTANCE AT TURN NUMBER 9 IS APPROX.  40.0
> U.H.
> THE INDUCTANCE AT TURN NUMBER 10 IS APPROX.  49.9
> U.H.
> THE PRIMARY INSIDE DIAMETER WILL BE 10
> INCHES
> THE PRIMARY OUTSIDE DIAMETER WILL BE 24.25
> INCHES
> IT WILL HAVE 10 TURNS OF .375 INCH
> CONDUCTOR
> THE TURN TO TURN SPACING WILL BE .375
> INCH.
> 
> Ok, I realilze that there was alot to this post, but if any of you have
> the time, could you please go over it and tell me where the design is
> wrong or suggestions on what to do to make this thing work, I sure would
> appreciate it!
>
> 
> --
> Nathan Lamphere
> http://www.ronan-dot-net/~randyl/nfolder/nathan.html
> Javascripts: WebPageMaker - easily create your own webpage right online!

Basically, the calculations look good! A toroid made from 4" aluminum
dryer duct and two back-to-back pie pans (approx. 16" outermost
diameter) will provide about the right amount of top-end capacitance
(about 17 pF derated down to about 13 pF when mounted atop your coil).

Good Luck, and safew coilin' to you, Nathan!

-- Bert --