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Congrats, Paul! Always feels good to make a goal.

I queued up a couple vids to make sure "nearly" is "actually." 

1uF, 5% tolerance.

I recommend buying sheets of the 66 cent stamps (they have a Butterfly on them) for shipping PCB's. You can use one of those in the US to ship the method described above (inside a thank you card) and mark it Non-Machinable (if you just use a forever stamp it will go through the machines). Slap 2 stamps on and you can ship international! Now if you are doing this as a business I would probably mail in flats within the USA. If not, just always make sure you have an extra PCB on hand in case something goes wrong...

Here is a link to the stamps:

https://store.usps.com/store/browse/uspsProductDetailMultiSkuDropDown.jsp?categoryNavIds=catBuyStamps%3asubcatS_S_Sheets&categoryNav=false&navAction=push&navCount=0&productId=S_115904&categoryId=subcatS_S_Sheets

It's 70c in the US now.

The Blackstone is regular split-shaft pots, sawed down. The PCB is recessed and mounted inside the enclosure.

Trimpots have terrible tolerance, bad noise performance, and also don't tend to allow fine adjustment easily. Those are all pretty good reasons to avoid using them when possible.

Putting holes in your enclosure that won't be filled with something means more RF. Something to think about.

But I can certainly understand the desire to reduce the number of knobs used.

I've had an odd one with PT2399's from Tayda. When doing a Sea Urchin I had to externally connect a couple of pins. Found via this post
http://www.madbeanpedals.com/forum/index.php?topic=7512.msg64852#msg64852

Took a while to find but they technically work.

That's all PT2399s, and a flaw in the Deep Blue Delay's design (which did little to correct the factory example schematic), nothing to do with Tayda's chips.

I like that the transformer survived.

1) Yep.

3) Woops, 22R. R9 in that schematic.
4) Correct. You'll see that sort of capacitor and resistor setup in a lot of compressors. The resistor drains off voltage from the capacitor (which stores it) at a fixed time constant.

I've spent a lot of time playing with these, and I haven't found a good spot that had as much info as possible in one place. Though they're not the most common LFO these days, I figured some people might have some questions, thoughts, or ideas about using or modifying them. Feel free to jump into the discussion there or here. Here's the thread:

http://www.diystompboxes.com/smfforum/index.php?topic=106566.0

Excellent recording. Not something I'd seek out on my own, but it's very well put together.

Plus, fuzz. Yum.

Merlin Blencowe's U-boat is the best analog octave down I've ever heard:
http://www.valvewizard.co.uk/uboat.html

The 3362P trimmers are the best deal anywhere.


Josh

I read that they are made by Alpha, same quality as the ones made by Bourns?

Ive bought bourn trimmers before and they are a million times better quality then the crappy little plastic ones tayda sell.   It was a bit of an eye opener for me actually.

Edit: I should say though the 'crappy' plastic tayda trimmers are ok for 1 off dialing in but if you need one for a test pcb or something that requires accuracy (BBD Delay) I wouldn't use them.

I'm talking about these:

http://www.taydaelectronics.com/potentiometer-variable-resistors/cermet-potentiometers/3362p.html

Not the ones they call trimmers that are the 6mm one turns, those are junk.

Josh

These are good if you need accuracy:
http://www.taydaelectronics.com/potentiometer-variable-resistors/cermet-potentiometers/3296w.html

I use the 6c "junk" ones all the time. I've never had any trouble. I do measure them first, though, if I care about getting the full marked value; their tolerance is terrible, over 20%.

I'm going to guess diodes is a 10K-25K pot in series with the whole diode shebang, and I think the best place for "density," if that's the bass control, would be a cap blend with the 2.2uF cap between the collector of Q1 and the base of Q2. It COULD be the 47uF on their emitters, but the pedal has a tendency to not work when that cap gets too small, so I'm not sure.

Also socket your electrolytic caps as this helps if you quickly want to swap them out. I just stick to the makes that are reliable

Socketting any part requires far more than just "it might be slightly inconvenient to replace it." Parts fall out of sockets, which is a heck of a lot more inconvenient than replacing one if it goes bad in 10, 20, or 50 years. This is much more likely to happen when you're forced to bend over the electrolytic because it's now sticking up an extra 5mm from the PCB.

My favourite is mylar film and electrolytic caps but it's personal preference. Don't forget  that its mainly about value and size.

This is bad shopping advice. Mylar film -- "greenies" -- unlike box caps are not of uniform length, width, or height. Box caps on the other hand are essentially standard through-hole parts that will fit nearly every PCB and are typically the same lead spacing as most standard 50V ceramic capacitors and MLCC caps. A 100nF greenie is about twice as big in every dimension as the same size of a box cap of the same value. A 1uF mylar film would be unusably large. They also tend to be much higher tolerance (20% instead of 5%). About the only thing going for them is that they're slightly cheaper, but that really doesn't do any good if they don't fit on the PCB.

There's a hole north of C1 on one side and another hole just right of the other side of that capacitor.

Put a 100K pot in series with a bigger cap ... let's say 22nF. That'll give a pretty wide range. You can hook it up like this:

1
2
3

1: (connect to 2)
2: Pad on the other side of C1.
3: One side of the 22nF capacitor.

The other side of the 22nF capacitor goes to the unused pad next to C1.

When the pot is at minimum, there is 100K of resistance in series with the 22nF capacitor, meaning it has very little effect on the circuit.

When the pot is at maximum, there is no resistance between lugs 2 and 3, so there is no resistance in series with the capacitor. It's now fully in the circuit.

Howdy,
I built a Quadrovibe ... the bypass works, the LED works, and flashes in time with the speed knob, but the lamp doesn't cycle off, ergo ... no effect

anyway, does anyone have any suggestions? from reading the build docs, my next guess would be to take a look at trying different values in R16 & 17.
another thing is that when I first adjusted the trimmers, I had to get the Chop close to all the way up before the lamp fired.
one other thing I should mention is that I used an ON/ OFF/ ON DPDT for the switch... I'm gonna put in an ON/ ON in a couple of days, when I get the part

thanks for your help!

The switch is limited to the audio path.

Are you getting varying voltages anywhere in the LFO?

Check R22 -- are you SURE you used a 47 Ohm resistor and not a 47K?