First of Thank you R.G. for providing this info for online use, it is a great Idea and will be a great addition to my bench!
You're welcome. Glad to help.
I figured out as much as the wiper on the volume would be the output.
I was confused about how to hook up the length and speed pots. At first I was thinking I had to do something from the switch sort of like Dave did. However, looking at his layout raises more questions. I see he has Tone and Note Lengths, but no speed pot?
I really should have explained that more I guess. It's kind of cryptic.
The section of IC1 with R1/2/3 and C1/2/3 on it is a sine wave oscillator with a fixed frequency. R1/2/3 and C1/2/3 set the frequency. It is a characteristic of this kind of oscillator that it has to have a very, very specific gain to oscillate without distortion. If the gain is too high, it distorts and is no longer a pure (-iish!) sine wave. If the gain is too low, it will start to oscillate at turn on, or at any disturbance, but it doesn't quite have enough feedback to keep itself going. If the gain is ***perfect*** it oscillates with a pure sine wave.
R4 plus either the "length" control or TR1, depending on where the switch is set, let you adjust the amount of feedback. The idea is that if you flip it to "Tone", by which I meant "steady, non varying tone" and finely adjust TR1, you can get a nearly pure sine wave out. The reason a sine wave is useful is that your ear can hear the difference between a sine wave and a few percent of distortion. TR1 lets you get a steady test tone.
If you flip the switch to "Length", you can adjust the amount of feedback so that when the circuit is disturbed by the "disturber" part of the circuit, the tone starts up, but dies away. The length pot lets you set this so it takes a goodly fraction of a second to die away, faking the sudden start, then trailing off of a guitar string being plucked. It's the electronic analog of pulling a pendulum away from rest, then letting it go, and coincidentally of plucking a taut string. You can, of course, set "Length" and TR1 both to do either always-on oscillation or dies-away notes. They do the same thing electronically. The difference is just how they're set and which one you put on the front panel.
Both pots cause longer ringing, getting into steady tones, at the biggest resistance. The little dot on the pot in the schematic is the clockwise-most terminal. When you turn the shaft full clockwise, it's closest to the dotted terminal. What that tells you is that the schematic intended for the pots to be hooked up so maximum clockwise rotation was biggest resistance. The connection from wiper to dotted/CW terminal is optional. You could leave off the connection to the dotted terminal of these pots and just connect the counterclockwise terminal and the wiper, ignoring the clockwise terminal, and the thing would work the same.
From R.G.'s Schematic I would presume that dave used a standard pot instead of a trimmer for the notes? Ok but is this the correct way to wire these pots up? or is this a good alternative?
"Notes" means "you get repetitive notes that die away" instead of a steady tone. "Tone" means "you get a steady tone that doesn't die away".
I saw R.G. say he was gonna post a layout, did I read that correctly? I feel so ignorant, many people have built this it seems but I seem to be the only one confused?
No more confused than I am. I had to go back and read what I wrote. By the way, you did make me find a mistake I put in there. The Speed pot is shown wired backwards. As it is, it gets slower as you turn the knob toward CW. The wire from wiper to CW/dotted terminal should go to the non-dotted/ CCW terminal instead, so the resistance goes down as you turn it clockwise.
For this one, the simple thing to do is get your pots, based on how you want the mechanics to look, and for the pots that probably means a front panel knob for speed, and maybe for length. I would use a trimmer for TR1, myself, but nothing says it can't be a front panel knob too. It's just that I didn't see adjusting it very often. When you get the pots, get out your meter, set to ohms, and connect one lead to the wiper. Hook the other lead to one of the outer lugs, then turn the shaft clockwise. If the resistance goes to nearly zero, that's the clockwise/dotted outer lug you're on. If it goes to the full nominal pot value, it's the non-dotted/CCW terminal. If it doesn't change, you guessed wrong about the wiper pin and have the meter on the CW and CCW pins.