[TowerTalk] Modifying Comtek 4-square controller(relay unit) for a different band?

[Lux, Jim]

On 11/21/21 11:11 AM, Michael Tope wrote:
> Hi Jim,
>
> Starting with version 5.0, EZNEC implements the capability to model 
> lumped transformers, inductors, capacitors, and resistors. Thus, it 
> should have capability to model the Collins 90deg hybrid. The only 
> caveat is that the transformer model is ideal (K=1.0), so including 
> the impact of flux leakage and core loss would have to be captured 
> with additional components in an equivalent circuit model. 


I wonder how they do it. An ideal transformer has no Z or Y matrix - for 
an ideal transformer you can't express the voltage in terms of current 
or vice versa.  And yet, various analyses do use transformers and 
admittance matrices.

I1 = Y11 V1 + Y12 V2

I2 = Y21 V1 + Y22 V2

You can't find Ys from I1 = I2 / N and V1 = V2 * N.


Lumped L R and C is easy.

Maybe an extension to the underlying NEC core? But NEC is all about 
creating a big Y matrix, and then solving it.