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Double check that you indeed have 27k on both R25 and R26.
Look for tiny solder bridges....use a magnifying glass if you have one. I use one all the time.
Is either IC1 or IC2 hot when you touch it?

100kB for the gain. It's used in the second stage. So, instead of that 100k resistor in the feedback loop, it's a 10k resistor in series with the 100kB pot.

This one is in the bag. Sounds good! The gain control worked out well....it adds enough versatility between unity and boost to warrant its inclusion.

The current board is a little too big for a 1590A, though. Since I only plan to offer one version, what's good for everyone? One knob or two?

Also, I think this one is probably best as true bypass. Does anyone care about being able to use it as buffered bypass?

Those are usually 1024 stages.

But, a slapback echo might be a good use. I don't know of a project off the top of my head that uses one.

Maybe try a search on DIYSB. I bet someone has found a use for the MN3002 there.

I should take a look at the gate function. Let me see how it could be implemented.

The stock unit used 5mm, IIRC. Either should be okay.

In this case, the square marking is negative on the board, although that is reverse of what it should be. I need to update that image to make the square marking positive!

I would not recommend this. The MN3002 is only 512 stages as compared to the 4096 stages of an MN3005. At best, you will only get slapback out of it.

I recommend going with the v3205/v3102 combo. These are readily available.

The Nature pot partially controls the total gain allowed by the op-amp, where the waveform is clipped and also which frequency range is boosted at Q1...all at the same time. It is pretty clever. When the pot is fully counter-clockwise, C3 and C4 are parallel to ground which results in a very broadly clipped waveform. This also means that there is a high resistance to ground (50k) in parallel with R11 and in series with C5.

When it's all the way clockwise, the resistance between C5 and ground goes to zero, which means that Q1 is boosting more midrange. It also means that there is a high resistance between C4 and ground. The result of this is that the overall gain of the feedback in the op-amp stage is decreased. That's why your LEDs are lighting up more when the knob is all the way to the left: that's where you have the highest gain possible in the FB loop.

Currently, the layout is very similar to the Thunderpuss: narrow, with angled ends and space for a PCB mounted pot. How does everyone feel about this? My thoughts were to try to get it in a 1590A, but I don't know how easy this would be to do. Should I make it larger and just assume everyone is okay with it going in a 1590B?

There is another size that the current layout could go in. It's the 1550Q / 1550P
http://www.mouser.com/Search/Refine.aspx?Keyword=546-1550Q
http://www.mouser.com/Search/Refine.aspx?Keyword=546-1550P

The Q is 2.36 x 2.17 x 1.06 and the P is 3.15 x2.17 x 0.83. The P might not be tall enough...I'll have to measure a 3PDT!

The best way to control the gain would probably at the first stage. A variable resistor could replace the 100k resistor in the feedback loop of the first amp. I'll see about incorporating this into the layout. Actually, I already finished the layout!

Although the frequency response could be altered I don't know the use of that yet. 200 - 1kHz is pretty broad. You could push it up into the 2-3k range to be more of a presence control rather than mid-range.

Another alternative to the LF442 is the TL062, which also has low power consumption. That's probably what I will try first, since I don't have the 442 either.

Looks good. I don't see any mistakes. I do prefer the bias pot hooked up the opposite way though. The way you have it when the pot is fully counter clockwise it will reduce the fuzz. When fully clockwise it will give you maximum fuzz. I prefer it the other way around because it differentiates it from the way the fuzz pot works.

One thing missing on your schematic is another 10pF cap between collector and base of Q2. On the '69, this is soldered on the trace side of the board.

I'll make this one happen. It does look promising.

I've now have the Quasar fixed up so you can build either the AC or RC on it. I'll have the project doc up in a day or so.

Welcome Nazim!

In response to your questions:
1) A fabbed board (fabricated) means that it is a design I have manufactured instead of making by hand. These kinds of boards are double sided copper, with solder mask, silkscreen, and plated through holes. Some of the designs are fabricated because I now have too many projects to do everything hand-made. The hand-made boards require a great deal of time and attention and it is impossible for me to manage the volume of orders any other way. Both the fabricated and hand-made boards are high quality--just different technologies. For the second part, fabricated boards usually lend themselves to smaller PCB designs. By routing traces on both sides of the board, you can make layouts that are much tighter than single sided designs.

2) There are two images of the PNP transfer on many of the documents simply as a convenience. When etching PCBs, many people like to do more than one at a time in case one doesn't come out well. I do this too (except in my case, I'm usually etching three or four 8x10" panels at a time full of different designs). The images are identical, as you guessed. These designs are always included in the projects, even for the ones that I sell that are fabricated. This is one of the main features of madbeanpedals: you can etch your own, or you can buy a PCB from me. It's always your choice

Please feel free to post any other questions you come across!

 

Your wiring diagram looks fine. Can you explain what you mean by "I didnt use a hookup for the 9v"...are you talking about the battery?

Any chance you could have wired the actual DC jack incorrectly?