Gerard,
It would be wise to check the inductance of your torroid using your nanoVNA.
Could well be that there is enough capacitance between windings to give poor results.
Surface mount inductors might work better.
If you don't have a datasheet for the 45mhz module, you will have to just try different caps and inductors
to see what's best, measuring the response with your nanoVNA.??
Figuring out how to do the calculations is a hobby in itself, but for a properly working filter
it all comes down to proper testing.
Jerry, KE7ER
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On Wed, Mar 27, 2024 at 07:13 AM, Gerard wrote:
In fact if I understood correctly it's give in the theory : 530nH (so 12 turns give 560nH in the tore calculator), and total of 16pF--> remove 3pf of the crystal filter--> so 13pF for capacitor
