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Re: MMC Question.

Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>

Hi Glen,

Your coil might end up more like 1270 turns or a little less. It's just a 20 kHz change.

The primary you'll want about 1" to 1.5" clearance between the coils (wall of secondary and start of inner diameter of primary).

The toroid is small for the coil. You will want something larger around 6" x 21". Should you eventually build a larger toroid, the coils frequency will drop to about 190 kHz. This will require retuning of the primary (from where it would be with the smaller toroid) about 2 or 3 turns "more". So, you can see that there is yet another reason to add 2 or 3 extra turns to the primary coil. Most of us experiment with different toploads and whatnot, so the extra turns come in real handy for coiling.

Regarding the resonance - no magic. The coils frequency relates to it's size and external capacitance which is coupled to the resonator (toroid size, coil base height, walls and ceiling, etc..).

Gary's comments regarding gap width is right on. You can get away with near or at resonant values for the tank cap, but if one wrong thing occurs like a failed gap or incorrect gap setting, it can be the demise of the NST. Thus, the recommendation for LTR (as it won't rise above the C limited voltage in both situations).

Well, vacation starting tomorrow. I'm going fishing!!!

Take care,

Tesla list wrote:

Original poster: "Glen McGowan" <glen.mcgowan@xxxxxxxxx>

Wooohooo......Got my primary and secondary in order (I hope). I had attempted to use JavaTC before but it looked confusing so I left it alone. I fiddled around with the numbers and came up with the following:

Resonance is 262.1Khz between primary and secondary.

Secondary is 4" x 23"  1215.47 turns of #26.

Primary is 10 turns at 1/4" spacing. (prolly use 13 or so)

Topload is 3x12 Toroid

I do have a question about Resonance....Is there a magic number that is optimal? I hear 200Khz thrown around alot so I stayed in that area.