Problems with Mad Professor Fire Red Fuzz

[gigimarga]

Hello all!

I've just finished a clone of MP Fire Red Fuzz using this layout: http://tagboardeffects.blogspot.ro/2012/02/mad-professor-fire-red-fuzz.html...by the way, thank you a lot IvIark for it!!!

I used BF245B instead of 2N3819 (which are hard to find here and I didn't want to use them for clipping) and 2N5484 instead of 2N5485.

My problem is that it has too much noise/hum, even if I use it only with a fresh battery. The fuzz isn't boxed yet, but I have a lot of Big Muffs unboxed and none has so much noise/hum.

All the collectors are around 3.8-4.1 V and the drain of the FET is around 5V.

I replaced the 470pF with 1nF, as I saw here, but with no luck :(

Anyone can help me?

Best regards!
Radu

[JaviCAP]

Evening!

Have not tried with 2N5484, but as Miro told, until he dropped a 5485, there was a lot of noise in the background. I can tell you that with 3819 and 5485 is a not noisy at all build.

Bjorn is one of the few builders that you can be sure that if he uses some specific model of trannie, there's a reason behind the choice.

So, the only way to know that a MP /Bearrfoot doesn't work as intended is to build it verbatim to the specs. If the circuit keeps on working bad once you build it sticking to specs, that's when you can start to look for problems.

I'd try to get a 5485 and some 3819, and check.

J.

[gigimarga]

Thank you JaviCAP for your advice!

I will try to find a 2N5485 (as I have 3 or 4 pieces of 2N3819, but I don't want to waste them for clipping), but I tested each stage separetely and it seems that the last one works good: a clean booster, not very strong.

Can you post the voltages of yours, please? As far as I know, mine are closer to the regular voltages of a Big Muff (first 3 stages), but, any way, I am curious :)

Thank you very much!
Radu