[Home][2019 Index] Re: [TCML] Coupling [Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [TCML] Coupling

Hi David,

I have never heard of single-turn primary coils used for Tesla coils. You're sure you're not thinking of a multi-LAYER primary? I have seen semi-toroidal dual-layer primary coils to improve coupling and field shape, but I have no experience with those myself. I'm strictly referring to the number of turns on a single-layer primary.

I'd be interested to see some data on Tesla coils with a one-turn primary coil, if that's actually a thing.

Matt, Fairlee VT

-----Original Message-----
From: David Thomson <aetherwizard@xxxxxxxxx>
To: derstrom8 <derstrom8@xxxxxxx>; Tesla Coil Mailing List <tesla@xxxxxxxxxx>
Sent: Sun, Feb 17, 2019 5:09 pm
Subject: Re: [TCML] Coupling

Matt, when building a Tesla coil, yes, you can make sparks with multiple turn primaries. Tesla's research, however, showed that the best resonators had just a single turn primary of a conductor, and that the conductor diameter of the secondary should be smaller than the conductor diameter of the primary. 
Doug's bipolar coil has two adjustable secondaries, making his setup ideal for a single turn primary. All he needs to do to get maximum coupling is to build a single turn primary and then experiment with the position of the secondaries until he get's maximum resonance. 
As Tesla reasoned, high voltage oscillators are Helmholtz resonators. Therefore the same physics that make a flute resonate are the same physics that make a Tesla coil resonate. The flutist will not become a better flutist by having extra pairs of lips, and neither does a Tesla coil become a better resonator by having extra primary turns. To make the Tesla coil work optimally, the primary should always be one turn of a heavy conductor, and the secondary should be built accordingly. If you want to tune the primary, use adjustable capacitance and adjustable input power. If you want to tune the secondary, adjust the primary/secondary coupling, the distance of the topload from the secondary, and the surface area of the topload. If there is coupling between the topload and ground, you could also adjust the resistance of the ground connection.
David Thomson

On Sun, Feb 17, 2019 at 3:42 PM derstrom8--- via Tesla <tesla@xxxxxxxxxx> wrote:

Hi Doug,

Is there any way for you to reduce your tank capacitance so that you can use more turns on your primary? I'm no expert myself but I'm thinking more primary turns and slightly less tank capacitance is better than very few primary turns and a large tank capacitance. Perhaps someone else could chime in here with better qualifications?

Matt Lewis, Fairlee VT

-----Original Message-----
From: Douglas Johnson <doug379306@xxxxxxxxx>
To: Tesla Coil Mailing List <tesla@xxxxxxxxxx>
Sent: Sun, Feb 17, 2019 4:24 pm
Subject: Re: [TCML] Coupling

Hi Gary, Thank you,  You can probably tell from most of my posts that I am
not very technical concerning this stuff, but I have an insatiable appetite
to learn. That said, I am continuing to try to improve the performance of
this little coil, since the video I have improved tuning until l now I am
getting " breakouts" from both ends. When I get the coil tuned to what I
think is optimum, which may include working to improve the primary. {I
think I have too many turns on it because I am down to using only about
three}, I will do another video, so any requests or instruction on what to
look for would be helpful.
Tesla mailing list

Tesla mailing list