First 1 turn is always though both hole there is no .5 turn.
Also if the inductance of the winding is not high enough you get a low
frequency cutoff. Changing the ferrite to higher mu (43 to 73) will help
but more turns would have as well.
The reason I removed a bit of a turn (and then called it half a turn) was this seemed to make a better match. Though in reply #11793 I accidentally called it 'one turn' when I meant 'half a turn', this may have caused the confusion. This message should have said 'half a turn' was 7.38uH and 'one turn' was 12.5uH.
When I calculated the required inductance needed using Xl = 4 x 50 ohm and then putting the 200 in to L = Xl / (2 x pi x f) I got 4.5uH. With one turn this measures 12uH on my inductance meter but with 'half a turn' it measures 7.38uH which is closer to the calculated value and why I tried removing a half turn to see what would happen.
I am currently using a BN-73-202 73 material binocular core for my tests, originally I was using an FT37-43 toroid.
