Re: Magnifying Coil

Hi Dan,

On 10 May 00, at 8:10, Tesla List wrote:

> Original Poster: "Dan Kunkel" <kunk77-at-juno-dot-com> 
> To all Magnifier Experts,
> It appears that my previous notions about Maggy coils are a little bit
> off base. In that case, I would definately like to review some more
> up-to-date info on the subject. Are there any on-line documents or
> downloadable files? The only detailed compreshensive source that I have
> seen has been compiled by Richard Quick based on his experiments on the
> subject. I will list the important details pertaining to maggy's as I
> understand them to be...please correct and add if you can.
> 1) Really tight coupling between pri/sec

The degree of coupling you get between primary and secondary 
and the proportion of total secondary+extra inductance you couple 
the primary to defines Ksys.  Here is a dead easy way to make a 
magnifier with lower than desirable coupling. 

- Take an ordinary working TC
- connect another resonator with moderate inductance to the top of 
it (remember - the higher this extra coil inductance, the lower Ksys 
will be)
- retune the primary (add some turns say) 
There you have it.

> 3) Pri should be a verticle helix extending almost the whole length of
> the secondary

True for high K

> 4) Sec is very low inductance and low impedence (space wound heavy gauge
> stranded wire)

Doesn't have to be but the voltage stepup you get in this portion is 
going to tax your pri-sec insulation to a degree commensurate with 
the secondary voltage

> 5) Sec should should have a fat ratio...~1.5:1

Again it's not necessary

> 6) Sec should be twice the operational frequency of the tertiary

Doesn't have to be - doesn't even have to be close actually.

> 7) Tert should be high inductance and high impedence (close wound magnet
> wire)

Doesn't have to be - Tesla's extra coil was highly space for example.

> 8) Tert should be heavily toploaded (and be half the freq of sec coil)

Heavy toploading always gets results if the resonator can stand the 
voltage the topload has to be charged to to "let go". The frequency 
relative to the secondary is not a requirement.

> 9) Tert should have a ratio of ~2:1

Doesn't have to - a 5:1 works just fine

> 10) Use a very fast break rate in the spark gap

Can be anything one uses with a typical 2-coil.

> 11) Connect sec and tert coils 6'-9' feet apart and use a loss conductor

I've built a couple of table top models where the coils weren't even 
separated by a foot. Voltages rule the day when it comes to 
clearances. I even mocked up a tabletop version of the CS machine 
with the pri-sec about 2' in diameter. The whole thing was scaled in 
size. Believe it or not, all K's were the same as the CS machine.

> (That's all I can think of at the moment)
> So if there are no real advantages secured from a magnifiying coil, then
> why build them? Maybe for looks, or something different, or to save a
> little space?

Main advantage in my opinion is to get the business end of the 
system well clear of the primary and anything else that would inhibit 
maximum sparklength.