Hello Remy,
What core are u using? I assume a FTxx-43?
I would try a 49:1 and a 64:1.
I made a few more winding’s then I connected it in my garden to the 20m long wire and I tried to match it that it goes to 50 ohms.
This was my result. Now I’m making every core with these exact windings.
For your understanding:
2 primary
14 secondary
16 total
16/2= 8
8^2= 64
So 1:64 transformer.
Correct me pls if I’m wrong.
And maybe drill the wire better. It looks like u made only 2.5 turns.
Happy crafting.
73
Julian