Inductor winding?

Once again, I come to you for help. I recently became interested in some kind of 555 device metal detector. The schematic calls for a 10mh inductor. However, my local Ripoffshack doesn't carry inductors, and instead I decided I could make my own. It's just a coil of wire right?

Right, so I have some formulas to find inductance given things like length and width, and I wondered if there's anything I need to be aware of. Does a ferrite core increase inductance? Where can I get a ferrite core? Do I need one? Is there a sweet spot for inductors?

Thanks, Mr. Merino

Ferrite cores make a big difference.

With them, its easy L = Al x n^2 where Al is a property of the core, and n is the number of turns. Rearrange for n.

Buy one from a supplier online like Mouser. An inductor that small will be hard to make by hand and hard to get that accurate.

mrmerino (author)  mpilchfamily4 years ago
Dammit, millihenries, not microhenries. I need to redo my calculations too, apparently.