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Guybrush- you've used a 16 pin IC socket for IC2 instead of a 14 pin. It's covering up R11.

R15 and R17 are standing resistors.

As a temporary measure, you can add extra caps for power supply filtering. A 470uF and 100n in parallel between + and - might do the trick.

What brand of charge pump are you using?

Yep, it does.

Thanks! The PCB etching artwork will be included in the project doc when the manufactured PCB is released.

This has occupied most of my week so far. My original prototype had numerous errors which kinda bummed me out. So, I decided to start over and do a single sided layout. My first attempt had the envelope detector set up more like the Meatball, with extra Attack and Decay controls. The LED drivers were pumped through a 2n3904 transistor with the base being fed by the output of the envelope. I managed to make a new mistake on this layout due to swapping an op-amp. But, I figured that out quickly and re-routed what I needed to under the board.

Anyway, this approach actually did not work out very well- The transistor seemed to be driving the LED too hard and it would sometimes "freak out". So, I removed the 2n3904 and got it going. But, the Attack and Decay controls just were not doing it for me. So, I started over again with another layout, this time setting it up more like the original. Now the envelope drives the two LEDs on the Vactrols directly and I added a Sweep control, which sets the intensity (this is Rx on R.G's "Neutron" project). That did the trick! There are a couple of other mods. I reduced the input gain a bit since at the very top of the gain it seemed to crap out. That was done just by increasing the input resistor a bit. The other mod is that the unit is true bypass, and an inverted output stage was added with a gain trimmer in case one needs a little more out. This means the input and output are now in phase, unlike the original Mutron.

Overall, I am really happy with it. The double sided layout is already done, and it is a variation of the layout you see here. The double sided layout will board-mount the pots and two switches. The rotary switch will be wired (only requires 4 wires).

The etch on this one came out really nice, even though I misspelled the name. That was probably because I rushed that like hell---I only spent an hour on it from design to finished etch. But, she looks real cool. Mostly due to the Cthulhu drawing which I swiped from the web.

Pig Butt and Rump Roast will come some time later. The Sparkplug is done. The Cave Dweller will be back in stock soon. I've made a lot of progress on the Nautilus, too.

I don't think it is a bad diode. It might be a bad solder joint around that pot. Scraping the cap casings with the jack probably did not damage them unless it was with a lot of force. Since your signal is intermittent I would go with reflowing the solder joints and double checking your wire connections. Try replacing the potentially bad pot if necessary.

These look terrific! And good on you for sticking with it to solve the problems with the CL. Don't sweat it too much. I question my abilities every day...sometimes I know more than I think but I tend to assume I know a lot less than I should. Frustration can really damper your spirits when you know something should work, but cannot figure out why it does not!

BTW: what's with the little paint markings on your transistors in the Faultline? That's pretty curious.

http://www.madbeanpedals.com/forum/index.php?topic=3482.0

Are you sure you have the correct value for R7? It's hard to read the resistor code because the light is bouncing off it.

How about if you remove IC1...do you get 9v on pin8 without the IC in?

Just to add to mgwhit's comments. In your average op-amp overdrive you have a feedback setup where you attempt to maximize the gain of the opamp to create overdrive. Op-amp clipping tends to be harsh and square, so we add diodes either in the feedback path or clip the signal to ground afterward to soften the edges and give it a more natural sound.

In the case of the BB, the goal is not so much to generate overdrive in the circuit, but lots of clean boost to drive the front end of an amplifier and goose into its own natural (and superior) overdrive. The split rail set up gives us a larger amount to "swing" the guitar signal so that we get the boost without the harsh clipping of the op-amp. It actually does not have a lot of gain. Rather, it has just enough output to drive the amp without getting brittle or harsh.

It uses split rail rather than an 18v setup because that allows one to use ground as a reference voltage to supply the bias of the op-amp rather than having to use additional resistors to create a voltage divider off an 18v supply. Reducing the part count lets one make the PCB footprint smaller---critical for 1590A builld.

First off, this is a model of how to start a tech help thread. Very detailed! And, you've obviously put in a lot of work to try and resolve it.

The first quick thought I have is: you did not mention the actual 3PDT. Any chance that could be the source of the problem? You got it working out of the harness. Then re-installed and your volume is bleeding off. One possibility is the input or output is bleeding somewhere on the switch.

Try this: disconnect the input/output wires on the jacks. Tack solder the input and output wires from the PCB to them to create a temporary 'no bypass'. See if you still have the same problem plugging straight through. If not, then your 3PDT is the culprit.

One other thought: you big blue cap there is sticking up past the top to the enclosure. Any chance when you flip it over, it is creating downward pressure on the PCB, and forcing a contact between the bottom of the PCB and the pot casings?

First thing to do is figure out where your repeats are going. You need to audio probe at the junction of R62/R44, then R48/C34 and lastly C5/R7. If the signal is dying out at any of those points then look for solder bridges, cold joints or bad parts on those.

For the squealing, you probably have your Clock trimmer too high. Try dialing it back some. That should eliminate the whine at the max delay setting.

I think your drill bit is too big! I've never had an issue with the snap ins coming out. I don't know exactly which size I drill to, but I can tell you on a step bit it is the 10th rung. Even the 9th rung will work if you push it in really hard.