Re: 3 Coil System Was: A photographic tutorial of Pancake Coilwinding...with movies...(fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Sat, 23 Jun 2007 23:55:09 -0700
From: Barton B. Anderson <bartb@xxxxxxxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: 3 Coil System      Was: A photographic tutorial of Pancake
    Coilwinding...with movies...(fwd)

Hi Dave,

Tesla list wrote:

>---------- Forwarded message ----------
>Date: Sat, 23 Jun 2007 20:16:48 -0500
>From: David Thomson <dwt@xxxxxxxxxxxx>
>To: 'Tesla list' <tesla@xxxxxxxxxx>
>Subject: RE: 3 Coil System      Was: A photographic tutorial of Pancake
>    Coilwinding...with movies...(fwd)
>
>Hi Bart,
>
>  
>
>>Most magnifier systems are of the classic design with an 
>>L1:L2 driver situated a great distance from L3 and coupled 
>>via transmission line. 
>>    
>>
>
>Perhaps that is the way most people make them, but it is hardly a property
>of the coil.
>  
>
When you mentioned what others could do with their magnifiers... well, 
knowing the list concept of a magnifier, it's indicative to me that we 
should clarify. I really shouldn't even use the term magnifier out of 
it's original context so that I don't confuse anyone. The coils we are 
discussing I think is better termed a "3 coil resonant transformer". 
That makes it easy and exact.

>>L3 is a standalone unit both in mutual 
>>inductance and the coil capacity itself with it's topload and 
>>ground. Those are completely different beast and follow 
>>different design rules which don't apply to this topic.
>>    
>>
>
>I disagree.  In the case of a solenoid secondary, yes, it is necessary to
>run a transmission line to the third coil to avoid inductive coupling.
>However, a flat spiral coil has its magnetic field tilted 90 degrees out of
>phase with a thin solenoid connected to the center terminal.  There is no
>inductive coupling at all.
>
I'm not following your logic. In the case of a standard 2 coil system 
using a flat archimedes spiral primary and a solenoid secondary, the 
coils are inductively coupled. Can you clarify for me?

>As for the capacitive coupling, that also exists
>with a transmission line.  At the end of the transmission line, whether
>connected directly to the third coil, or connected to a flat plate near (but
>not touching) the bottom of the coil, there will be capactive coupling.  The
>capactive coupling will only be as good as the resonance matching of the
>secondary/primary system to the third coil.
>  
>
Absolutely.

>As you have demonstrated to me (intentionally or not), capactive coupling is
>the means for driving the third coil in acoustic mode.  
>
Unintentional. The acoustic mode you are theorizing is not something I 
understand.

>Many magnifier coilers have found that in order to get sparks out of the
>third coil, they actually have to be untuned.  If the third coil is
>perfectly in tune with the secondary/primary system, standing waves develop
>in it that have a high potential at the top load, but no current.
>
L3 is not magnetically coupled in standard magnifiers, but they are 
electrically connected. The primary of the driver must be tuned to the 
combined inductances of the L2 driver and the L3 extra coil. What 
appears to be "untuning" is nothing of that nature. The added inductance 
of L3 will cause the primary to be tuned to a lower frequency. So, 
they'll end up increasing primary inductance or change the capacitance 
to suit. Regardless, it's tuned (won't do well if it isn't).

>  Jeff also
>seems to be seeing the same thing when he removes the brass tube.  If he
>were to try brass tubes of different lengths, he will find the streamers
>actually disappear as the tube becomes resonant with the primary/secondary
>system.  When the tube is exactly in tune, he will get no streamers at all,
>but will likely get the standing wave coronal discharge I got on my system.
>
I disagree. The tube will capacitively load the coil out of resonance 
"if" the coil is tuned without the tube in place. Tuning must occur 
after everything has been fully assembled and in position. If he were to 
add a longer or larger tube, he would be required to retune the coil to 
it's new resonant frequency.

>>Very few have built 3 coil systems of helical design as my 
>>hybrid maggy. 
>>A few of course have with flat coils, but I'd bet in nearly 
>>every case, it was similar to your coil in design where the 
>>solenoid resonance was determined by the L1 and L2 with L3 
>>observed only as a capacity. Trying to get all three resonant 
>>through trial and error would be nearly impossible and a 
>>program would certainly be needed. Trial and error is very 
>>easy with a 2 coil system but not with a 3 coil system as we 
>>are discussing.
>>    
>>
>
>You are right on this.  That is why I'm going to run some tests to determine
>the speed of acoustic waves in electrons for copper and aluminum.  This
>information should prove valuable for eliminating the trial and error phase.
>Also, cutting a piece of copper pipe to length and then shaving it down to
>fine tune it will be a lot easier than winding coils.
>
>Also, it is important we understand that a perfectly tuned third coil will
>not produce any streamers.  However, it should produce a strong standing
>wave electrostatic field.
>  
>
Well, not in my experience. My 3 coil resonant transformer had all 3 
coils tuned to resonance with each other (they were all matched in 
frequency) and it produced streamers just fine.

>>You mentioned that anyone could replace the 3rd coil .... 
>>with a pipe of same dimensions and get the same results. That 
>>is true only if:
>>1) the 3rd coil is a close proximity coil as L1 and L2 are.
>>    
>>
>
>I would bet a transmission line leading to a flat disc would also excite the
>third coil if the disc and third coil were in close proximity.
>
>  
>
>>2) L1:L2:L3 are not designed to resonance.
>>    
>>
>
>I would agree if your intention is to get streamers.  If all three are in
>perfect resonance, there will be standing waves on L3, which will be all
>potential and no current.  
>
That would be my intention (streamers). I just haven't found this when 
I've done it.

>>3) L1 and L2 are resonant and L3 is seen as a capacity (which 
>>it is when 2 above is not true).
>>    
>>
>
>I don't see how L3 will no longer be seen as a capacity just because it is
>in resonance.  I think what you mean to say is that L3 will not produce
>streamers when all three are in resonance.
>  
>
I'll try to clarify. First, of course there is a capacity with L3. What 
I intended to get across was that L3 would not be seen as only a 
capacity. When L3C3 are resonant with the other two coils, then (and 
only then) do we have a 3 coil resonant transformer capable of higher 
potentials. We are also capable of higher coupling between L1:L2. L1 is 
tuned to the combination of L2 and L3 combination resonant frequency's. 
Likewise, L3 is designed to resonate at the combination of L2 and L1. 
This is what makes a difference in output potential. If L3 is just a 
solenoid of wire and is not made to resonate with the rest of the 
system, then the other two coils will determine the output potential and 
L3 will simply act as if it were a cylinder (although, depending it's 
frequency, it may be near some harmonics of the driver fundamental).

>>But, if L1:L2:L3 "are" designed to resonance, the game 
>>changes, especially in a system with a flat secondary and 
>>helical solenoid.
>>    
>>
>
>I believe the special result of the exact tuned combination flat spiral and
>solenoid is exactly for the reason I stated.  There is no inductive coupling
>at the center of a flat spiral because the magnetic field is completely out
>of phase with the solenoid.  Therefore, there is no need for a transmission
>line.
>  
>
On paper? In my experience, the magnetic field lines of the flat coil 
"will" intersect the solenoid and there will be inductive coupling. Tell 
you what, I can measure this with my small closewound flat coil and a 2" 
solenoid about 9" tall. I'll report back the coupling.

>BTW, I am making progress with your JavaTC program.  It helped me to see
>that my capacitor was too big for my present system.  I managed to fix the
>IE problem of timing out by following your instructions.  I also managed to
>change the default settings.  However, when I changed the default top load
>parameters to zero, I got an error when the script booted up.  How do I
>comment out the "add_toroid();" line in Java?  Also, what would be the
>similar data input lines for the solenoid?
>
I'll send a separate email to you on this.

>The pupman list is filled with an abundance of good information and tools
>for coilers.  I made a big mistake not looking into JavaTC sooner.  You have
>done a fine job with it.  I'm sure the programs of others are just as good.
>  
>
There are plenty of good programs out there. Antonio's INCA is 
excellent! You should try them all to see what you prefer. All programs 
of old and new will get you into the ballpark. When it comes to topload 
effects, older programs throw in a percentage the topload loads Fr. This 
percentage was close as long as you built coils to a particular 
geometry. But, with Javatc, that guess work is gone and now we can look 
at a lot of various geometry's and toploads. It can get a little 
complicated and it's slow (that's the downside). Antonio's is a compiled 
program and will run at lightning speed compared to a javascript code 
that isn't compiled (which is the reason it's slow).

>I have been working off Ed Sonderman's Excel sheet for the past ten years.
>It was good for its time, but your program is so much better.
>  
>
I used Ed's spreadsheet for a long time. Eventually I built my own 
spreadsheet. As things were added over time, the spreadsheet grew far 
beyond the original. Back then, not everyone could run the spreadsheets 
due to operating system variations, flavors, pc knowledge, etc.. So, to 
allow everyone to have the capability of using a program for coil 
design, I threw Javatc together (with a browser everyone could use the 
program). That was the original intent. At the time, it was a copy of my 
spreadsheet in an html form running simple math equations. It's of 
course doing a lot more now thanks to Paul Nicholson.

Take care,
Bart