Re: Jonathon's 6"-Tuning was 2nd light of the "Green Monster" - sec vs. pri height

["Tesla list" <tesla@xxxxxxxxxx>]

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

Hi Jonathon,

Not to worry, the specs you gave were fine. It's not what I'm looking 
for, but what the specs actually are that matters. Given the 1" 
clearance between pri and sec you described (along with primary 
specs), k = 0.142 when the bottom sec turn is level with the primary. 
Not bad. It could go higher, but given the sec cannot physically go 
below the primary, it's fine.

Based on your topload specs, the coil should tune in at 8.15 turns if 
running outside. In an enclosed environment (say a garage) the tap 
doesn't change much on your coil. It should tune in at 8.25 turns. 
Hardly a difference. This is actually a nice feature of your coil. On 
my 8.5" coil, there is a very noticeable difference of about 1 turn 
between outside and inside running.

Your coil would probably do best if the sec was 1/2" below the primary.

BTW, I always quote program specs here, yet I always run inductance 
high on the primary (between 5 and 15%). By the percent here I'm 
referring to the sec and pri frequency's. You find that many coilers 
run a little high on pri inductance. The reason favored that 
streamers add to secC, thus, we tune for the bigger streamers.

With that said, I can say "some days are certainly better than 
others" and "some days suck"!

Take care,
Bart

Tesla list wrote:

> Original poster: Kidd6488@xxxxxxx
> Ok, my site is at 
> <http://hot-streamer.com/jonathon>http://hot-streamer.com/jonathon.
>
> The specs aren't the greatest on there however... I just measured, 
> and the closest point between the primary and secondary is 1", but I 
> think the value you are looking for is somewhere between 1.25" and 
> 1.5" (the next few spots were).  860 turns on the secondary does ring a bell.
>
> The primary is only 10 turns maximum (and just barely, actually like 
> 9.9).  I could try to add to this, but it might not come out pretty.
> Depends on how much it matters.  My topload is 4" dryer duct between 
> piepans.  I measured and it is 16" Diameter (major, or 
> outside).  And about 4.5" tall.
>
> I'm realizing now how poorly engineered this thing actually is.
> Flaws:  *Only 10 turns available on the primary (ran out of Cu pipe, 
> can probably solder more on though).  *Secondary cannot be set below 
> primary (could be changed if absolutely necessary.  Last resort 
> though.)   *Topload too small (Wanted to make a new one anyways, any 
> suggestions on bigger toroids, easily?)
>
> Thank you all! Its great to be getting back into this again.....
>
> And as far as outside diam. of primary, I'm not sure right now, but 
> I can measure that tomorrow if necessary...
>
> Thanks again
>
> Jonathon Reinhart
>
>
>
> In a message dated 8/9/05 1:42:46 AM Eastern Daylight Time, 
> tesla@xxxxxxxxxx writes:
> Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>
>
> Hi Jonathon,
>
> The primary data is minimal (need to know inner and outer diam.).
> BTW, your cap is 0.0167uF and your sec turns are closer to 860.
>
> Based on your coil data, if the flat pri is level with the bottom sec turn:
>
> Pri to Sec clearance = 2", then coupling "k" = 0.125
> Pri to Sec clearance = 1.75", then k = 0.128
> Pri to Sec clearance = 1.5", then k = 0.132
> Pri to Sec clearance = 1.25", then k = 0.135
> Pri to Sec clearance = 1", then k = 0.139
> Pri to Sec clearance = .75", then k = 0.144
>
> It's funny, for such a long time coupling was always a "measured"
> sport. Nowadays, it's probably the #1 most accurate output of our programs.
>
> Based on this data, it's likely you will achieve best energy transfer
> when the sec bottom turn is below the primary. But, as you can see,
> it helps to know the inner diameter. If I had that, I would have
> given the various k values at various heights.
>
> BTW, regarding your 11 turn primary. If it is tapped at 11 turns,
> then you would need about a 37pF topload (9"x33"). I'm not sure of
> the topload size you have but I doubt it's that big (maybe). If the
> topload is something less, then if tapped at 11 turns, the coil is
> definitely out of tune.
>
> Take care,
> Bart