Can these inductors work for a wah?

[zener]

I've been googling lately on how to make an inductor for a wah and I stumbled into this company.

http://www.wilcocorp.com/catalog/category.cfm?category=ferrite_drum

Another thing, what can I sub for the MPSA18 on the circuit. I think that is a NPN, right? 2N5088, 89 or 2N3904? Any issues?

Thanks :wink:

Zener

[MarkB]

they have a 470 and a 560...  and they offer samples..
hmmmmm
"-)

[Roland]

I believe the 470 and 560 are microhenries uh . What you want are millihenries. Looks like they have 800 ma 22mh , so 2 of them in series would work, but probably too large . Hammond makes a 470 mh part# 622Y  nominal Q of 45 at 10khz and a dc resistance of 218 ohms, low profile pc mount.

[zener]

I believe the 470 and 560 are microhenries uh . What you want are millihenries. Looks like they have 800 ma 22mh , so 2 of them in series would work, but probably too large . Hammond makes a 470 mh part# 622Y  nominal Q of 45 at 10khz and a dc resistance of 218 ohms, low profile pc mount.

Oh, how I didn't notice the uH symbol :?  Maybe because I'm always seeing uF in caps :roll: .

[brett]

what can I sub for the MPSA18 on the circuit. I think that is a NPN, right? 2N5088, 89 or 2N3904?

The MPSA18 is good because it is both VERY low noise and high hFE.  The 2N5089 is the best alternative, then 5088.  A 2N3904 is too noisey and maybe too low hFE.  Small Bear stocks the MPSA18 for a very reasonable price (if I buy 10 MPSA18s and a few other things he has cheap, he often works out cheapest for me, even with $4 postage to distant Oz).