Superfuzz layout from Keen's PCB Layout book....

[Solidhex]

First off I dig the book. Learned a lot. Thanks Mr. Keen! Anyone out there have a schematic that would correlate to the Superfuzz featured in the book? I'm just pretty much looking for the values of all the components... R1=? C1=? I have some schematics but I'd really hate to build the entire thing and flub it with a dumb mistake. Especially since its not the most simple of circuits...

--Brad

[MartyMart]

http://www.univox.org/pics/schematics/superfuzz2.gif

Is it this one from Univox ??
There's another from Marshall that's a little different ....
MM

[Dan N]

http://www.univox.org/pics/schematics/superfuzz2.gif

Is it this one from Univox ??
There's another from Marshall that's a little different ....
MM

Be careful with that schematic. On the two upper right transistors, both base to ground should be 22K and both base to V should be 100K.

I like this one :

http://www.univox.org/pics/schematics/superfuzz.gif

[Solidhex]

Yo

  Thanks guys. I've come up with this list using the second schem but there's some other questions raised..first here's the list. If you see anything amiss let me know!
R1) 1m pull down
R2) 22K
R3) 100K
R4) 1.8K
R5) 47K
R6) 10K
R7) 470K
R8) 47K
R9) 100K
R10) 3.3K
R11) 220K
R12) 150K
R13) 10K
R14) 10K
R15) 470 ohm
R16) 100K
R17) 22K
R18) 1.8K
R19) 10K
R20) 100K
R21) 22K
R22) 470 ohm
R23) 47K
R24) 10K
R25) 22K
R26) 10K
R27) 100K
R28) 15K
R29) 10K
R30) 1K
R31) 1m pull down

  Now for the caps
C1,3,4,6,7,8,9,10,11,14,and 15) 10uf electro
C2) .002
C5) .1
C12) .001
C13) .1
 
Now for the questions...in the schematic R17 and R21 are routed through what I assume is a 10k trimpot to ground but in the Keen schem there is no variable resistor. The octave balance right? Is that trimpot unnecessary to the circuit?
  Also in the Keen schematic there are 2 caps listed as C15. One is the output cap and the other is a cap tied from the 9v supply to ground. Once the the layout gets started in the book the 9v to ground C15 cap dissapears? Its not in the univox superfuzz schem but I was wondering why it was in the Keen one in the first place. A mistake?

Rock, Brad

[Dan N]

The small box Superfuzz did not use a trim pot. It is a nice addition to help get the sound "just right". Both versions used a 10uf cap between V+ and ground.

[R.G.]

Is that trimpot unnecessary to the circuit?

No. It is there to help perfectly balance the two transistors for a better octave. It can be (ab)used to make a variable octave.

Also in the Keen schematic there are 2 caps listed as C15. One is the output cap and the other is a cap tied from the 9v supply to ground. Once the the layout gets started in the book the 9v to ground C15 cap dissapears? Its not in the univox superfuzz schem but I was wondering why it was in the Keen one in the first place. A mistake?

It's a mistake. I should have put it on the board. Quoting myself from page 72, near the bottom:

To remind me that I've left some things out, I have put the parts that aren't part of a particular stamp yet out above the board edge outline. There is a goodly chunk of the circuit in the parts that are not yet placed. This is a really good trick to use to be sure you don't forget to put a part into the board. The most error prone part of the process happens behind your forehead.

So I guess the topic is covered, and in the correct chapter, too... 

[Solidhex]

Radical!

  Thanks R.G. Here I go....

--Brad

[ringworm]

Sorry for the necro post but I was wanting to clarify something about the Superfuzz circuit.
There is a 10uf electrolytic that is connected to the 9v power supply in the second version of the schematic posted in this thread, it is marked as 5v is this correct and if so does it affect the sound any to have a 10v (or anything higher than 9v) capacitor in it's place and why does it not fry being only 5v?

[gmr1]

As an aside, I got this book christmas time, and I've read it twice and referenced it a bunch. This book, along with "Electronic Circuits - Fundamentals and Applications" (Tooley is the author), have been a great primer for me to start to really understand the building blocks of a circuit.

[R.G.]

There is a 10uf electrolytic that is connected to the 9v power supply in the second version of the schematic posted in this thread, it is marked as 5v is this correct and if so does it affect the sound any to have a 10v (or anything higher than 9v) capacitor in it's place and why does it not fry being only 5v?

(a) It is incorrect. If you could find a 5V cap ( 6V is the closest to that available today) then it would probably fail being run at 9V; even if it didn't, it would be luck. Electro caps should always be specified over the largest votlage they will see. A 50V cap would work in that spot, for example.
(b) It has no effect on tone to have that cap be 10V, 16V, 25V etc. In fact, I suspect that "5V" is a typo, and it should read "25V" or "50V". In the words of Napoleon, never ascribe to malice what can be explained buy incompetence.

[ringworm]

Thanks fer that folks.

[drewl]

So somewhere I stumbled upon BYOC has a "Leeds" fuzz I guess like Townshends superfuzz.
Is this same one?
What's with the 6 transistors?
How's this thing sound, do I NEED to build one?

[Mark Hammer]

In the words of Napoleon, never ascribe to malice what can be explained buy incompetence.

I have never had to buy incompetence: I come by it naturally!

[yeeshkul]

I finished mine yesterday. 2sc828s, OC91 diodes, 2n2 cap, no trimpot. I followed the factory schemo and put it on my own PCB that fits BB. It is wild and surprisingly quiet - i mean no hum, not much hiss.

http://www.hoho.cz/efekty/sounds/superfuzz.mp3
http://www.hoho.cz/efekty/sounds/superfuzz2.mp3 comparison of the 2 fuzz tones