# Re: Maggie help needed

```Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <twftesla-at-uswest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
>
> Original poster: "michael.tucknott by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <michael.tucknott-at-virgin-dot-net>
>
> Hi Antonio
> It was late and thats all I`m gona say, glad you spotted my mistake the
> primary and secondary
> numbers should indeed be swop around.
> As for the for dimenshions:-primary is H = 9"  by  D = 13 3/4"
>                                           Secondary H = 9 3/4" by D 9 1/4"

Ok. So, trying the coils in the acmi program, I get:
L1=79.3 uH
L2=0.775 mH
L3=10.7 mH
k12=0.497

The coupling coefficient is too high for the values of L2 and L3.
The coupling coefficient should be sqrt(L2/(L2+L3))=0.26,
or L2 should be higher, 3.5 mH.
With this L2 you need rather high capacitances at the top of L2.
Assuming that you can change k12 by rising L2 above L1, or modifying
L1, the closest modes that I found were (I assumed C3=20 pF. Only the
ratio C2/C3 is important):
7,8,11:   L2=0.772 mH, C2=192 pF, k12=0.259
10,11,20: L2=0.784 mH, C2=100 pF, k12=0.261
11,12,13: L2=0.740 mH, C2=93.7 pF, k12=0.254

For L1=80 uH, and assuming C3 as really 20 pF, The primary
capacitance should be only 2.9 nF, to satisfy the relation
L1*C1=(L2+L3)*C3

A table with values up to mode 15,18,29 is at:
http://www.coe.ufrj.br/~acmq/magt.txt

Regards,

Antonio Carlos M. de Queiroz

```