RE: JavaTC and ETesla6 Questions

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

Original poster: "John H. Couture by way of Terry Fritz <twftesla-at-qwest-dot-net>" <couturejh-at-mgte-dot-com>


Terry, Adam -

The operating frequency for the secondary coil with toroid should be about
97 not 114 Khz. For example enter into the JHCTES Ver 3.3 on-line program
for the secondary inputs only (The power transformer and primary inputs are
not necessary):

Sec Rad = 4.06      Sec Turns = 1600.9
Turns/inch = 1600.9/69 = 23.20
Sec above primary = 0.00
Sec Term pf = 22.4 (estimate)

Press calculate for Outputs -
Coil self cap     = 23.29 pf (Medhurst equation - long form)
Total sec cir cap = 23.29 + 22.40 = 45.69 pf
Oper Freq         = 97.65 Khz

The 6 x (18+6) toroid = about 28 pf (from Grapf)
When placed on the secondary coil the pf reduction is estimated to be about
20% or 5.6 pf. The program sec term = 28 - 5.6 = 22.40 pf

The only way to find the true reduction of toroid capacity when placed on
the sec coil is to properly test for the actual capacity after the coil and
toroid are built. This simple test is shown in the Tesla Coil Construction
Guide and other books.

The test consists of finding the actual frequency of the sec coil with the
toroid in place. Going back to the JHCTES program the sec term pf input of
the program is then adjusted until the test frequency appears in the program
outputs. This new sec term pf will be the true toroid capacitance of your TC
system and will be close to the 22.40 pf design capacitance.

The amount of reduction (about 5.6 pf or 5.6/28 = .20) can then be easily
determined. Note that the 20% reduction is only an estimate and will vary
depending on the construction of the sec coil and toroid.

You can arrive at a similar conclusion with JavaTC and ETesla but this
requires more work on your part.

John Couture

----------------------------


-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Sunday, September 01, 2002 7:21 PM
To: tesla-at-pupman-dot-com
Subject: Re: JavaTC and ETesla6 Questions


Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Adam,

The toroid capacitance for Java TC is too high.  I "think" you want 33.36pF
- The seconday coil's self capacitance of about 24pF for toroid
capacitance.  That is about 9.44pF.

33.36 - 23.92 = 9.44pF

Cheers,

	Terry


At 11:06 AM 9/1/2002 -0700, you wrote:
>Please excuse the long post.
>
>I'm getting ready to build another coil, and was
>attempting to use JavaTC and ETesla6, when I ran into
>something that didn't seem right. To begin with, I
>plugged the following into JavaTC:

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