Re: How should we measure coil efficiency, was neon vs. potenti
From: John H. Couture[SMTP:couturejh-at-worldnet.att-dot-net]
Sent: Wednesday, August 06, 1997 5:58 PM
To: Tesla List
Subject: Re: How should we measure coil efficiency, was neon vs. potenti
At 04:27 AM 8/6/97 +0000, you wrote:
>Sent: Tuesday, August 05, 1997 6:08 AM
>Subject: Re: How should we measure coil efficiency, was neon vs. potenti
>In a message dated 97-08-03 08:59:25 EDT, you write:
>- snip -
><< You would have to design your coil with sufficient adjustment for a wider
> than normal range. The optimum frequency may be the reason that the present
> musical toroid game is being played.
> It should also be noted that you would only get more output if your input
> source was capable of providing more input. This means that the input
> wattage source should be matched to the possible optimum output. There are
> several optimizing conditions in the design of TCs that I believe are being
> presently ignored.
> John Couture
>This means that an average coil like mine, 6" dia, resonant frequency around
>110 khz (if I remember correctly), pole pig power supply, etc. - would have
>a particular power input level that would produce the longest discharges.
> i.e. set it up as normal, large toroid, primary tapped for best spark at
>maybe 1 kw in plus about 1/2 turn, then gradually increase the power by
>decreasing the ballast and there should be some power level, probably short
>of maximum that would produce the longest sparks. Is this what you are
>saying?? Anyone recall seeing this in their experiments?
One of the advantages of having others review your work is that they will
bring up questions not considered before. With your question you have
approached the optimum frequency by starting with the frequency which is the
reverse process. To answer your question you need to find the wattage for
the 110 KHZ frequency. To do this you need to reverse the original equation
W = (KHZ+96.4/3032.5)^-3.614 -1 /.2767 = - 3.614
For 110 KHZ this equals 16,515 watts. However, it is obvious this approach
would not work with a 6" coil or any small coil.
I ran into the above when developing the JHCTES TC computer program and
this is one reason why the program starts with the input watts. There are
many things that must be taken into account when developing a comprehensive
Entering the 16,515 watts into the JHCTES program you can then obtain a
large variety of parameter possibilities for a 110 KHZ coil. One of the many
combinations is as follows. A few of the 46 program parameters are:
Pri spiral 14"inside dia - 23 " outside dia - 3/4 inch OD Cu tube
52 uh - Total 7 turns - tunes at 6.13 turns
Pri cap - .04 uf - 40 KV
Sec coil 14 " dia x 33.3 " long - 550 turns - 37.4 mh
# 16 Formvar - 1.5 mils thick K factor = .14
Toroid 12" x 46 " - 43 pf - 110 KHZ
Spark 14 Ft continuous
After this TC is built you would then find the best adjustments for
longest spark at the 110 KHZ frequency. You would then change the frequency
by increasing and decreasing the Toroid capacitance and pri turns and
measuring the spark lengths. These spark lengths would be shorter than the
110 KHZ sparks..
To test your smaller coil you would have to pick an input wattage,
calculate the optimum frequency, and rebuild the coil for that frequency.
Then after you find the adjustments for the maximum continuous spark length
at the calculated frequency, change the toroid and pri turns and check the
spark lengths. I would be interested in what you find.