Fuzzrite clone help!

[Mike Vilogi]

Hello
       I am about to start working on my 3rd pedal. This will be my fist pedal that isn`t done with pre assembled kit parts, so I am ordering my individual parts for the first time. I have run into an issue trying to figure out what rating of Caps I need. Attached is the pic I am working from


I notice they use 2nf Caps. I was sourcing alot of my parts from Mammoth and couldn`t find anything in nf rating, most were in uf. Should I be converting these ratings to uf? If so, I found some close in uf conversions, but not dead on. What should I do? Is there a specific composition I should be using for this? IE Electrolytic, Tantalum, etc?

Also, I am able to find the 2n3904 tran. Is there anything else I should try out? Last time I built a fuzz I did an NPN germ with sockets. It sounded great, but whenever I threw in silicon it was nice, but pulled in TONS of noise. Should I buy bulk sil. tran. to pick through the bunch, or was this a kind of fluke noise issue I don`t need to worry about to much?

Thanks for being patient and helping, I am still new at this.

[LucifersTrip]

Hello,

Firstly rating means the voltage it can handle...you're talking about value. Here's a chart:
http://www.justradios.com/uFnFpF.html

You can basically use any caps as long as they're RATED 9V+.

Suggestions: make Q2 lower hfe than Q1. If you have on hand, under 100 hfe for Q2.
Try different values for the tone control. I prefer the germanium far more than the si version,
in both sound and vol/tone control.  Try 500K/350K (ge fuzzrite) or 250K/200K (ge orpheum) for
vol/tone.

[LucifersTrip]

ps: by tone, I mean fuzz...

if you have too much noise, try small (50pf) cap across Q1 BC

[smallbearelec]

Hi Mike--

Closest standard to 2 nf is 2.2 nf. That is notation more common in Europe. 1 nf. = .001 mf., and that's how I list all my small value caps. 2.2 nf = .0022 mf., and that will work here. Closest to 50 nf. is .047 mf. You want poly film for the small caps, electrolytic for the 100 mf. 2N3904 is very common and anyone should have it, my SKU 2006.

If you build the Fuzzrite, Breadboard It First. Many transistor combinations are possible, and the residents here will have suggestions. I notice the reverse-polarity protection diode is parallel-connected. Not my preferred way to do this, because the failure mode is destructive. IMO, better to use a series-connected Schottky like a 1N5818; you only lose 200 mv. of supply, and the diode does not pop in case of reverse power connection.

Re silicon in the FF: You can't necessarily sub random silicon devices and get good results. Again, you have to go back to the breadboard, pick devices with appropriate gains and bias correctly. There is no reason that a properly lined-up silicon FF should be noisy.

[darron]

The 2nf sounds mega thin anyway. After building it stock you might feel like beefing them up to put a little more bottom end in. Otherwise it's only really useable for lead.

[duck_arse]

regarding your transistors: whatever parts you do get, find and download the datasheet for same. look at the pinouts on the datasheet, and compare them to the layout diagram, which is at best misleading for the newer builders. one or the other will face-flat the opposite direction.

[Mike Vilogi]

So is the photo of one of the transistors supposed to be flipped?

[darron]

So is the photo of one of the transistors supposed to be flipped?

if you're going by the photo, yes.


they are the same tranny but one says  EBC and the other CBE so will need to check which way the go in for whichever you use. for the older stuff base is almost always in the centre.




i made this circuit with some lower-ish gain NPN Ge's and it did exactly what it was meant to. i was happy. every time i've tried something else it hasn't really been right.