On Sep 7, 10:45*am, bpnjensen wrote:
On Sep 6, 4:54*am, dxAce wrote:

*http://www.dxing.info/equipment/impe...ing_bryant.pdf

Here I think is the original article by John Bryant which appeared back in the

late 80's in Fine Tuning Proceedings (though this one is dated 2001):

*http://home.comcast.net/~markwa1ion/...ansformers.pdf

Used here for over 25 years.

dxAce
Michigan
USA

What I like best about these two articles "side-by-side" is that the
later article shows why an evenly and fully wound core is superior to
the partially wound core with the windings separate - due to loss of
field intersect when the core is not fully covered. *Love this, thanks
~

Bruce

BpnJ,

Note - A1 & A2 are the same point on a Ferrite
Toroidal Core {Donut}
http://www.goldmine-elec-products.com/images/G6683B.jpg

# 1 Two Separate and Opposed Coils
A1=====================A2 Ferrite
.......mmmmmm..........mm........
----------- 30T ------------- 10T --------
http://www.automatic-windings.co.uk/...mages/1239.jpg

-or-

# 2 Two Coils Spread-Out Evenly Around the Core
First the Larger Coil with many turns : Then the
smaller coil with fewer turns laid over the first.
A1=====================A2 Ferrite
.......m....m....m....m....m....m... = 30T
............n......n......n......n.......... = 10T
http://t1.gstatic.com/images?q=tbn:3.../coil1.jpg&t=1

-wrt- # 2 the 'Techie-Think' on this is :
1st the Coils themselves Couple better.
2nd the entire Surface and Mass of the Ferrite Core
{it's Magnetic Properties} is more effective used to
Couple the Two Coils.
Result : Coupling Synergy is Achieved
1st (1) &(+) 2nd (1) = 4 ~T~ Mucho Better !

of course there are the exceptions to
every good idea ) ~ RHF
http://www.overunity.com/index.php?a... 45161%3Bimage