#45

Ok, I’ve started soldering my own build (thanks again for the board @crucFX!) and digging back into all my notes here and references noted above since my original suggestion for writing up the cross nodes seems not to be correct. I reread this bit from Richard Brewster’s page on making his Tetrazzi modular:
Quote:Shown above is Peter B’s schematic for one of the four Tetrazzi oscillators. It is an ingenious design for a voltage-controlled sawtooth/ramp oscillator, where the up and down rates are separately voltage controlled. Not only are the rates under VC, each VCO has two modulation inputs, one for up (UPMOD) and one for down (DONMOD), that are hard-wired internally to come from the other VCOS. The internal patch looks like this:

UPMOD cross connections: [1 -> 4; 4 -> 3; 3 -> 2; 2 -> 1]
DONMOD cross connections: [4 -> 1; 4 -> 2; 2 -> 3; 2 -> 4] Unquote.

This lead me to consider that there are two nets of cross modulation not just one. (I am making the assumption that the numbers here refer to quadrants and not the cross number.) In the schematic above, the DONMOD pot is on the left and it’s modulation point is 1 Star. The UPMOD pot is on the right and it’s modulation point is 2 Star. Within each quadrant the are 2 similar crosses and these have to be connected together to match the schematic. This is the “3 star” and “channel out” area I marked just above the piezo in the schematic. As noted before, I based the schematic off of the bottom left quadrant. Let’s call this quadrant #4. Above it is #1 and clockwise to #2 and then #3. If you connect those two 3 stars together and then to the 3 star in #3 it begins to follow the UPMOD pattern. Here’s all four color coded:

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The UPMOD bit makes sense to me and kind of what I thought the whole scene was, but the DONMOD isn’t circular as Richard describes it. What you do get if you connect the remaining similar crosses is another circular pattern like so:
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I’m still not sure if this is right but it’s closer to what Richard described.

One more detail is that until now I didn’t realize that quadrants #1&#3 use different input pins to the 4051 than quadrants #2&#4. I think this another way to add chaos to the interweaving of the oscillators.

EDIT: I just read this again and I realize it’s not as clear as it could be (like all my posts in this thread. :upside_down_face:) I’ll look at all this again tomorrow and see if I can make it more plain.

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#46

I believe Quadrant 1 is the Right Top Quadrant (indicated by having 2 Single Star nodes), Quadrant 2 the top Left Quadrant (indicated by having 2 Double Star Nodes) etc.

^ this is just my theory because Peter loves to do shit counter-clockwise.

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#47

All that being said tho - I gotta lotta wires to move around hahaha.

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#48

Actually, not a lot maybe…
I think if you just remove one wire from each cross grouping it will separate the UPMOD from the DONMOD.
Give me a minute to check and I’ll add a diagram.

If you wired them in a series before (hard to tell from the pictures) you should just have to remove the purple wires to separate the two:

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Here it is with the correct quadrant numbers:

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#49

I will try this out in a bit and let you know!!

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#50

lol - clipped all the suggested clips and now i get no sound lol
im gonna pull all of the “internal wiring” and start fresh

#51

But do the piezos work now?

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#52

no - get nothing at all

#53

:thinking:

I’m fresh out of ideas…I’m gonna have to take a break from this for a while until I get my own board populated and can do my own hands on testing. Good luck and keep us updated on your experiments good and bad.

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#54

I DO think you’re onto something though with the wiring -
Think it would be worth shooting a board over to Pugix?
He commented on my Youtube video " wow you made a board of the paper circuit"
I explained to him in the comment that a fellow DIY’er in the Lines forum made this and we’re all trying to figure out the wiring lol.

#55

It’s your call. I don’t know him well enough to ask. Seems like you might.

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#56

Something that may be worth noting -
Quadrant 1- 4051 I/O 2-Star, 3-Star, 4-Star
Quadrant 2- 4051 I/O 1-Star, 3-Star, 4-Star
Quadrant 3- 4051 I/O 1-Star, 2-Star, 4-Star
Quadrant 4- 4051 I/O 1-Star, 2-Star, 3-Star

O.o

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#57

That would sort all the troubleshooting in 1 go.

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#58

:slight_smile: He agreed to take a look :smiley:
(Pugix, I mean)

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#59

Hi guys! Just when i thought i had the wiring nailed i came to see that it is still all up in the air. Well, i got my boards today and they are much bigger than expected. This project seem daunting for now and i am kinda afraid to start something i can not finish. Sorry for not having much to contribute but i guess if pugix gets his hands on a board it is just a matter of time before it will all make much more sense. I gotta admit this must be the most interesting diy ciat lonbarde project i have seen so far and i am very very excited about it. Thanks Josh for the gerbers and leading me into ordering some pcbs.

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#60

Welcome Kristen!
I’m finding more time to populate my own board and soon we’ll have another one to test wiring out on.

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#61

I completed enough of my Tet to start playing around last night. I’m concentrating on one quadrant by not connecting any crosses and only that piezo. Nothing great to report, most of the same results that @crucFX has had.
My note (and @crucFX’s related elaboration) about the different wiring to the 4051s sent me back to the schematic and this time I traced out the star connections for all the quadrants:

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In this schematic, I color coded the stars. Within each quadrant, a colored line is a hardwired connection on the board itself. Near the bottom of each quadrant, the two star numbers next to one another are the two similar stars in that quadrant that need to be connected to match the schematic.
Of particular note is the fact that quadrants #1 and #3 use in/out pins 15,12,1,5,2&4 (pin order 2,3,4,5,6,7) and quadrants #2 and #4 use in/out pins 13,14,15,12,1&5 (pin order 0,1,2,3,4,5).
Related to this, and @crucFX’s comment, the stars related to UP are, in counter clockwise order, 4,1,2,3 The stars related to DON are similarly, 3,3,1,1. :thinking:
I have a feeling that that all the info is there (along with Richards description of the connection order), I just can’t see the answer yet. Getting closer!

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#62

Sorry about the delay on this - I am sending a board off to Richard tomorrow :smiley:
Gonna send him some other goodies as well :slight_smile: So maybe there will be writes ups for some others in the future as well (5-star brain, aulos rungler pitchbender logics, Chainlock, Rungling, etc. :slight_smile: )

#63

No apology necessary! Thanks for taking the lead on this.
I’ve tried a few other things in the past weeks but without any good results, so I really had nothing to report.:frowning:
Hopefully Richard will have some insight.:pray:

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#64

Crossing fingers and toes for this to happen! :pray:

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