Perf Layout for a Fuzz Face Build

[chuckfalcon]

Hi everyone.  I have been spending the night in DIYLC trying to come up with a "simple" and "clear" layout for my Fuzz Face build.  I am using pad per hole.  Let me know what you think and if you have any ideas of what could make this thing more clean, please let me know.  Here is the schematic I am going from:



Here is my layout.  The reason the Q1 and Q2 are so big is because they are socketed.



Thanks for your time and potential help!

[smallbearelec]

Good! You have clearly learned enough of DIYLC to produce a first try! Please take a look at my drawing in Figure 65 of this article:

http://diystompboxes.com/barebonesfuzzface/

While I do not claim that my version is "ideal", it may give you some ideas for improvement. Especially, draw pots and indicate clearly where the connections to them will go. Also, I would add reverse polarity protection and an input filter cap. Some people just use a 100 ohm resistor rather than the Schottky diode.

Keep going! Learning to do a workman-like (R. G. Keen's term) job of layout (about where I am for simple boards) is a process. Once you get to something that you are happy with when committed to solder, your drawing becomes a basis for making a PCB or getting it made for you. The latter step involves downloading a CAD program (like EAGLE), learning to use it, and re-drawing your pattern. Then you can generate Gerber files that a fab-house will work with. Though I'm sure someone will point out that OSH Park will work directly from an EAGLE.BRD file. I have done this to get made my last couple of prototypes.

[duck_arse]

here's my 2c, and I want any change back, thanks.

I'd try all these things, they may all go together, or none at all, starting with: rotate the 33k 90 degrees so it lays upside the 470R.

rotate Q1 90 degrees clockwise, then shift it to the right as far as you like. this should sharten up a few traces.
rotate Q2 90 degrees clockwise as well, to unwind its traces.

you'll need to add a pull-down resistor on the input cap.

basically, just say to yourself (with a few spare hours) - what if I put that there instead ..... and see what follows.

[Ben Lyman]

Have you bread boarded this yet? I've only made 6 FF's but I learn a little more with each build and I feel like it is very important to test it on the bread board before committing to solder.
+1 on the reverse protection, pull down resistor & power filter.
You might want to replace the 8k2 with a 10k trim pot so you can set the bias properly, check out Small Bear's tutorial, it's the most comprehensive, easiest to understand.
I have also had a lot of RF interference problems with the FF and I find a VERY small resistor at the input can solve it, usually about 100 ohms. If anybody else has an RF cure, please let the world know!

[chuckfalcon]

Hey everyone, thanks for the quick replies.  I worked on it some more last night and made some positive headway. 

-Yeah, I breadboarded before I started the layout and it worked (to my ears)

-If I replace the 8.2k with that variable resistor, where do I put the 3rd lead?  Ground?

Can anyone tell me the advantages of "pad per hole" and "strip board" (whole rows of holes are connected).  Is the strip board always easier/more practical?

I am going to work on it a bit more and post pics of what I have. 

[antonis]

If I replace the 8.2k with that variable resistor, where do I put the 3rd lead?

To upper lug (schem), if you want to raise gain CW..
(lower leg of 8k2 at your board - node of C3/470/8k2)

[duck_arse]

generally, if you find you have a pot or a trimpot with an unconnected clockwise [or counterclockwise] leg, you short/connect it to the wiper lead. this is good practise for if the wiper fails (they do).

stripboard is"ok", but it only goes left-right, whereas your frustrations tend to go up-down. perf goes where you tell it, so has fewer restrictions/limitations than stripboard, or veroboard. both are still valid construction methods, just different ways of thinking.

[Electric Warrior]

Can anyone tell me the advantages of "pad per hole" and "strip board" (whole rows of holes are connected).  Is the strip board always easier/more practical?

Much easier for me. On pad per hole you should connect the pads with component leads. Some people do this amazingly well, for me it's just an annoyance. On strip board you just solder the lead to the strip. It has most of the flexibility of pph and most of the convenience of pcb. Best of both worlds for me.

[chuckfalcon]

you'll need to add a pull-down resistor on the input cap.

What is a pull down resistor?  I know what the input cap is but not so sure about that resistor, what it does, what value should be used.

I am more than likely going to be adding a voltage inverter to my build at some point so I can use a standard 9V plug, and daisy chain. The one I am thinking of adding is this: http://3.bp.blogspot.com/-p41sc9zjSEw/Ute2GBD1dMI/AAAAAAAAF70/owslltSwwKg/s1600/Negative+Voltage+Inverter.png

If I were to add that.  Would I still need to used that pull down resistor?

[Electric Warrior]

It can prevent popping noises when switching the pedal on or off.
If you wire the switch like in a vintage fuzz face, with grounded input in bypass mode, popping is not much of an issue..

[chuckfalcon]

OK, after working with it a little more this is what I got.



Fore sure a lil' more organized, and I swapped out the 8.2k with a 10k trim.  No drop down or external trim pots just yet but that's next!

Lemme know what ya think!