[sdiy] filters, inductors & Q

[Ingo Debus]

Am Sonntag, 23.01.05 um 22:34 Uhr schrieb René Schmitz:

> Hi Jürgen and all,
>
>> Hi Rene,
>> but isn't it a pain to wind torroidals? I mean, even compared to
>> winding ordinary inductors ...
>
> Well that depends of course on your personal pain threshold. :-P
>

Hi Jürgen and René,

could it be that you both are referring to different things?
I mean, a true toroid inductor (like a toroid mains transformer, 
Deutsch: Ringkern) is indeed difficult to wind by hand.
Except mains transformers, I think I've never seen inductors of this 
type with many winding turns.

There's also that other type (Deutsch: Schalenkern, I forget how these 
are called in English), where the space where the winding(s) are is 
sort of toroidal, and surrounded by the core material. These are pretty 
easy to wind, since the the windings are on cylindrical plastic 
carriers. After the winding job is done, the carrier and the two halves 
of the core are assembled.
I remember using these inductors when I built a beat frequency 
oscillator when I was a kid.

Ingo