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The voltages on pins 7 and 8 of the PT2399 look wrong to me. They should be closer to the bias voltage, I think. I will check my voltages tomorrow morning to confirm.

Awesome, keep it coming!

And, YouTube pages related to your DIY builds are also much appreciated.

I added the 10R resistor based on a suggestion made a while ago by a forum member concerning Zener protection diodes. If an over-voltage diode should fail, it will short the power to ground, so the suggestion was made to put a current limiting resistor there. I decided to use the lowest value I had, which is 10R, and since I also had some 1/2W I went with that thinking it would be better for noise and/or heat dispersion.

Honestly, the only math I ever invoke on pedal design is for filters so if the math shows a better solution than what I put there, by all means. You could use a 47R or 100R 1/4 resistor in place of the 10R without any negative effects, I think (a slightly higher voltage drop). I think the I recorded the voltage drop over the BS250 and 10R combo at around 100mV.

Page 7 incorrectly labeled the wiring diagram as Buffered Bypass. It is actually the True Bypass wiring. This correction has been made and the PDF has been uploaded.

As I am gearing up to box some projects and do demos of them, I noticed that it has been a VERY long time since I did the last YouTube video. The main thing that keeps me from doing more isn't so much the boxing up and rolling the camera, but rather all those things combined with doing artwork. Artwork adds at least 2-3 hours to everything in my experience and I just find it difficult to set aside the time to create it, etch it and then clear coat it (which requires another day at least to dry).

So, if I were to do more video demos of projects but in generic type boxes without artwork or just hand-labels will anyone care? Does the look of the demo influence whether or not you want to build something? I think maybe it does. But, I also think more video demos would be helpful in the long run.

Please add your vote and give your feedback, if any.

I know some people here have their own blogs to feature/show off their builds (I don't mean just MBP stuff). I was thinking it would be nice to have these linked up on the MBP site proper as a resource. If you have such a thing and would like it featured on the MBP website, please post the link here (for convenience). This can also include PCB stores, if you have one. I have a few shops on the "Links" page, but I have no problem adding even more for members here.

Just connect the fx input to the input jack and the fx output to the output jack. couldn't be more simple. If you want an LED, just tie it directly to ground and it will light when the power supply is connected.

Coming up in just a few.

Interesting question. First idea that pops into my mind is a switch that grounds lug 3 of the Dirt pot. and shorts lugs 1 and 2 of the Clean pot simultaneously. You would need a DPDT, or a 3PDT is you want an LED indicator to show which mode you are in.

I doubt that the FCC will ever go after the little guys like boutique builders. They have little chance of making it worth the effort, I reckon. It's easy enough to target the major players where the big money is to be taken. 450k is a massive payoff compared to 1k from your average Christian Landowner (sorry, inside joke).

Still, it's a bummer.

I think you're probably right, but where it would worry me is it being used as a weapon by some butthurt competitor.

That....is very scary.

I doubt that the FCC will ever go after the little guys like boutique builders. They have little chance of making it worth the effort, I reckon. It's easy enough to target the major players where the big money is to be taken. 450k is a massive payoff compared to 1k from your average Christian Landowner (sorry, inside joke).

Still, it's a bummer.

Use the 3n9. When you consider tolerances it is probably better to be just a bit above 3.3. rather than (possibly) below 2n7 in this case.

Following this post I thought of a good mod: the "Squish" switch. Moving the bias point of the collector of Q2 down (well, technically up since it is a negative voltage) from -4.5v to somewhere between -2.5 to -3.5 v has the effect of "squishing" the fuzz a bit. It gets you a little more into the Eric Johnson fuzz range and is actually quite pleasant to play. Here's how it would work:

Socket R3 and jumper it. Dial the Bias trimpot until you get into the -2.5 to -3.5v range on the test point. Use your ear to find the right "squish" amount. Once you find that start trying different value resistors in R3 to get the test point reading -4.5v. It will probably be somewhere between 1k and 4k7, but YMMV. Leave the resistor in, and wire an SPST (or SPDT) switch to either end of the R3 socket legs on the bottom of the PCB. When the switch is off it gives you the normal bias. When the switch is engaged, it shorts R3 and goes into "Squish" mode.

If anyone feels like trying this, let me know how it turns out.

I just thought of a good mod. An external switch that takes you from -4.5v down to about -3 to -3.5v. Call it "squish" 

Here, I typed up how I think the mod would work: http://www.madbeanpedals.com/forum/index.php?topic=15306.0

Too low of a voltage at the bias test point means too high resistance going into the collector of Q2. Are you also using the bias trimpot, or did you jumper that out and just use 11k for R3?

What I would do is go with the default set up. the 220R resistor and 20k bias trimmer means 11k is right in the center of the trimmer. You could easily adjust it from there to reach -4.5v.

Also, remember that -4.5v is a target but not necessarily definitive. Some fuzzes sound quite amazing biased lower. They take on a very squishy, Eric Johnson type tone.