I wound a FT37-43 with 10 turns and measured it at 42 uH, just like it says.
https://www.electronics-tutorials.com/basics/toroidcharts_mcq.htm
Also
Electronics & Stuff, a lot about LEDs
I wound a FT37-43 with 10 turns and measured it at 42 uH, just like it says.
https://www.electronics-tutorials.com/basics/toroidcharts_mcq.htm
Also