[sdiy] inductor source?

[Fernando de Izuzquiza]

I'm interested in filters using coils.
I have a few links.
If people get interested after some tests we could do a group buy maybe.
It would be great to have schematics of the filters you already built!

http://www.cinemag.biz/inductors/inductors.html

Mouser 42TM013 : it makes a decent 500mH inductor, two should have to  
be used.

http://www.diystompboxes.com/smfforum/index.php? 
topic=51510.msg386760;topicseen

http://www.sowter.co.uk/acatalog/EQ_INDUCTORS.html

Inductance of some RadioShack transformers:
http://www.muzique.com/lab/tips.htm

Plus Halo, Fasel, etc: around 500mH for Wah.

There's also "wind your own inductor" kits around in Wha circles.

Fernando




El 13/12/2006, a las 5:55, David Moylan escribió:

> I've had fixed filters on my mind a lot lately.  I built an effect  
> pedal
> format LC filter box a few years ago that could do boost or cut at two
> frequencies simultaneously.  Each band had 12 possibilites.  It was
> essentially passive with make up gain and sounded fine but the  
> topology
> limited the effective Q.  That didn't bother me too much as I was  
> using
> it primarily for gentle shaping of guitar.
>
> I used a series LC circuit since in that case the Q is dependent on  
> the
> L, so it would remain relatively constant when switching between caps.
> And the caps were wired in series around a rotary switch.  That's the
> way it's done in Orange amps and it seems to keep the pops down.
>
> It was built with samples I ordered from Wilco. I've been fooling  
> around
> with it some more: increased the Q some which I liked.  Then,  
> realizing
> I don't use the cut position much I changed the topology to only  
> boost.
>  This is more in the fixed filter family since you get no signal with
> both knobs down.
>
> I like it a lot.  I can take a simple saw (with some LPF) and go from
> something akin to an upright bass to something that sounds like a  
> mouth
> harp or rubber band to insect tones.  Since it seems effective and  
> since
> the MOTM fixed filter is a dead project I think, I'd like to expand on
> my own little fixed filter.  I figure 3 or 4 switchable bands would be
> almost as useful as 10 single bands but where can I get 1H or larger
> inductors?  Judging from how hesitant Wilco is to give me a quote or
> tell me a minimum quantity they don't want to deal with small  
> potatoes.
>  It's too bad.  I like these little shielded inductors.  Do they have
> distributors?  Are there any alternatives?  Or is there enough  
> interest
> to try to get a group buy together?
>
> Yes, I know resonant filters can be made without inductors, but they
> make it so damn easy.  And aren't they more fun?  I haven't had any
> problems with hum pickup with these little Wilco BSL series.   
> Hopefully
> Harry doesn't feel about inductors the way he feels about BBDs...I can
> hear it now....
>
> Dave
>