Hand-wound copper foil transformer

[uncle_leon]

Hi all,

I was toying with the idea of winding my own transformer - but using copper foil/ribbon as a conductor, rather than round wire. The rationale being that foil is generally agreed to be superior to wire for inductors - and transformers are essentially coupled inductors...

I can buy toroidal cores from transformer manufacturers, and I can get copper foil by dismantling a foil inductor, and then enamelling it with some kind of lacquer or varnish.

Any suggestions why this is a good / bad idea?

Also, how can I calculate how many metres of conductor I need for such transformer?

I will appreciate any advice.

[abraxalito]

Who agrees that foil is superior to wire for inductors - do you have any references? One application where this seems to be true is in speaker voice coils - edge-wound with rectangular x-section seems to be superior to normal wire as it makes better use of the flux. However, voice coils aren't designed to be inductors - inductance is parasitic and attempts are made to minimize it.

Hard to get the foil to lay flat enough on a toroid to make neat windings wouldn't you say? I can just see it puckering up...

[Tony]

smps transformers uses them......

[tinitus]

Originally Posted by uncle_leon

The rationale being that foil is generally agreed to be superior to wire for inductors

it is, and it isnt
that kind of hysteria trends are quite common in hifi, unfortunately

to me, the small and cheap wire wound inductors still sounds better than even expencive foil ones

admitted, with bigger inductors wire wound is impractical
but then we are approaching wire wound toroids
those are worth doing, but a real pain to make

btw, you will need an LCR meter