Minima Filter Simulation

Well,

As my sweep of the 15MHz filter didn't look so clever, I've entered the design into QUCS:

This is the result of the simulation:

So that looks somewhat perfect! I need to check my build and also measure the inductors to check that my "theoretical" inductors (number of turns et cetera) actually measure correctly once wound.

So measuring the actual inductors I find I need about 1 turn less than theory on the T50-2 coils in the 15MHz filter. I have removed 1 turn from each and now my filter sweeps like this:

So it's better than it was but still far from perfect.

This is the inductors in the build now:

I will be very interested to learn what others end up with and if we can make a better match to the theory above!

Good, egh?