Weener Trannies

[MikeM]

Hey folks

I don't have a very good understanding of SS goodies, and I am planning to try my hand at a wah as a first pedal soon.

Can get most of the goodies I need here in South Africa, but transistors are relatively limited..

The pdf calls for a 2n3565, BC549C, 2N5457. I can get a hold of the 2N5457. But not the others. It also mentions that the 2N5088 is an alternative. Would that work for both of the others? I can also get BC107s, and actually quite a few others which I have just spotted here if anyone has the time to scope a page or 2 out for me.

What would the difference be between these though? Aren't they all little amplifying goodies?

Thanks very much folks!
Mike

[jkokura]

You can use pretty much any NPN that has a similar sort of function to the ones listed. I don't know about the BC107 off hand, but if it fits in that range also you can. Check the datasheet. I know that using BC108 or 109 transistors is quite popular in Vox Wah Mods.

Check the pinout on any transistor you want to swap in. A safe bet is to buy extras of different kinds and 'auditioning' various trannies for what sounds best to you.

As for the differences, as I mentioned there may be a different sound that you get using different kinds. Yes they all amplify, but they amplify with different strengths and flavours. Does that make sense?

Jacob

[MikeM]

Ahhh alright that makes sense, so pretty much tube rolling  

Can also get the 108 and 109.

Just confirming, can I use the same transistor for both needed in the actual wah?

Thanks very much Jacob

[jkokura]

Yes, but you can use different ones as well. There are few hard and fast rules in DIY building.

Jacob

[Haberdasher]

I think my dunlop came with mpsa18's in it which are pretty high gain.
If you wanted to approximate the gains of the ones in the build doc, I think bc549c's are about 550hfe.  So 2n5088 would go great right there but the pins are the other way around so just face it the other way.  The 2n3565 is about 250hfe i think?  So a similar gain range could be found in a 2n3904 or 2n4401.

But there are probably hundreds of npn trannies you could use in there and they would sound fine.

[MikeM]

Thanks guys!

Going to get

BC108B
BC108C
2N4401
BC549B
BC547C

2N5459 (Can't find the 5457 as this supplier, and this is supposedly just a lower gain equivalent?)
2N3819
2SK0163
BF245C

Should keep me busy for a long while!

[Haberdasher]

I used a 2sk117 jfet in mine.  It looks like the jfet in the circuit is there for the switchable buffer so it probably won't make much difference which one you use.  the 5459 ought to be fine, just check the data sheet to make sure you get the legs in the right order.  I had to make the 2sk117 do a little bit of "ballet".

[MikeM]

Yea, I figured it'd be as easy as checking where the base, emitter and collector would be and just comparing it to what would have been stock. Think I'll be able to figure it out

Now just to order the pcb, whipple and pot!

[gtr2]

um..this topic subject is disturbing... 

[MikeM]

It'd be even more so if it was swapped around 

[TNblueshawk]

Has anyone found a source for the 2n3565? I have some 3904's but I have to place an order for some stuff so I'd like to order up the 3565's but the usual suspects don't have it.

[DutchMF]

Banzaimusic.com has the 2N3565, I'd drop them an e-mail before ordering, as they don't list availability on their site

Paul

[Haberdasher]

Has anyone found a source for the 2n3565? I have some 3904's but I have to place an order for some stuff so I'd like to order up the 3565's but the usual suspects don't have it.

smallbear dude.
http://www.smallbearelec.com/Detail.bok?no=282

[TNblueshawk]

Has anyone found a source for the 2n3565? I have some 3904's but I have to place an order for some stuff so I'd like to order up the 3565's but the usual suspects don't have it.

smallbear dude.
http://www.smallbearelec.com/Detail.bok?no=282

WTF! I simply missed it. Dang. I ordered from them a few weeks ago and didn't see them! Just overlooked it I guess. Thanks.

[Haberdasher]

well crap, I just noticed someone went in & bought all the 2n3565's.  I needed 3 or 4 of them, too.