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Yes, take a look at the CDII in the project doc. You can use the same method to generate a mix knob for the repeats. Use a 50kB pot, wire lug 1 to lug 3 of the dwell pot. Wire lug 2 of the mix pot to ground. When you turn it up, it adds resistance to ground. When it's down, it brings the delay signal to ground. It's not a volume knob in the sense of a voltage divider, but it works well in the CDII, at least.

I've had that happen with an amp before. Some electrical plugs are just dirty.

It will be available again. I have yet to decide whether or not to redesign it for PCB mounted pots.

That could contribute to a volume drop. If you are still experiencing it after plugging in the matched transistors you have on the way, you can increase the output by reducing the value of R3. Start with 10k and work your way downward until getting unity.

That is strange. Trying a different outlet is a good idea. Maybe an alternate set of cables? Or, larger PS filtering caps on both effects.

You can use either or both. As long as you use at least one.

All components it's the same exactly with boneyard PDF.charge pump you mean the maxx1044?I make my own layout because I want small PCB.it's etched PCB.you think to check the joints??I send tomorrow the layout file and photos.it is necessarily to resolve the problem

Showing us the layout will help diagnose the problem in case there is something wrong with your charge pump configuration.

FWIW: I matched mine to about .5%, but I also measured about 50 devices. What you have may be fine. You just need to try it out and see if you get good phasing. Socketing the transistors might be a good idea in case you need to get some more closely matched ones.

I would first clean up those solder joints on the PCB for the wires to the pots. There is too much solder there. There might be some hairline solder bridge you can't easily see. Just hit the joints with a solder braid to suck up some of the excess then remelt the joints with your iron to make sure you have good contact.

[I did make two changes from the stock BOM:]

Q4 and Q5 were swapped on the layout pics and schematic of the Collosalus doc even though the BOM listed the correct parts for both. Just to be clear: Q4 is BC549C and Q5 is 2N5087. I have updated the layout and schematic pics in the doc. http://www.madbeanpedals.com/projects/Collosalus/docs/Collosalus.pdf

Also, to follow-up on some of the clock noise/ heterodyning issues I encountered with a 9v supply (as mentioned in this post): The noise appears to only have been a problem with my prototype build. I built one of the production boards (which had a couple of changes from the prototype layout) and had no problem with noise.

I did make two changes from the stock BOM: I replaced D4/D5 with 1N5817 (origin. 1N4001) and C26 with 100uF (orig. 10uF). It worked perfectly fine with my 1-Spot and had no noise at all. I also used a 1M pulldown which I did not have on my proto board, but that likely had nothing to do with the noise.

If you do run into clock noise, try those changes!

Cool, glad it worked out. Good call about C1--100n is usually more than enough. 470n is a bit overkill, IMO. Maybe they chose that for impedance reasons? Dunno.

You can't jumper C1. It's there to decouple the AC guitar signal from the DC path of the effect. Reducing cap values generally means reducing bass response, not the other way around.

Increase C3 to shift the range of clipped frequencies downward. A 220n or 330n should suffice.

I got an email from Smallbear letting me know they made some changes to their website which may cause some of the links in the project documents to become broken. Unfortunately, I don't have time to deal with this right away. In the meantime, if you are unsure about a part/component linked up to SB in any of the build docs, please feel free to ask here for help. The issue is not on their end---it's the non-updated links in the docs.

It gets fairly out of control, almost oscilation. It sounds like a constant feed back and keeps going and going until I turn it down to regain control then bring it up. Its an awsome noise rock delay and using a kickdisk type control I have it doing some awsome sped up/slowed down analog tape like stuff. Maybe its just the settings Im using? anything over 12 o clock it gets crazy.

The dwell control will oscillate somewhere around or after the midpoint. That is normal. The "secret" is to use the dwell and echo controls together to find the right balance. Setting the Echo around 25% and the Dwell just before the midpoint should give you almost infinite non-oscillating repeats that are somewhat dark sounding.

As gtr2 mentioned, the longest delay times will have some artifacts/digital noise to it due to the minimal filtering. You should not hear this at medium delay settings, so if you are experiencing that I would double check those resistor values. The gains stages are balanced for very clean output (as much as possible with this design). Using an electrolytic for C14 instead of tantalum should not make a big difference. The tantalum is preferable for filtering the 2399 from everything I have read, but I have built many delays based on that chip using only an electrolytic there.