#25

what an incredible undertaking holy smokes

#26

@Coitmusic @crucFX Thanks for the feedback.

I’ve updated the Osmond PCB files, Gerbers, PDF and PNG in the Github repo.
I’ve rerouted the MIDO layer so that it passes through components (perpendicularly) rather than close to pads, where possible.
I’ve also deleted those extra files from the zipfile, so KiCad should be able to read it without any errors or warnings.

@corpusjonsey Thanks. Any help is appreciated.

3 Likes
#27

Another day, another update.
I added the drill paths file back into the zip file, as without it the preview on JLCPCB was showing no drill holes. That would have made building tricky! :slight_smile:

3 Likes
#28

Thanks @barrford! I should have some more time in the next day or so to do some further looking at the board and compare it to what we’ve discussed.
I’ve also been looking at the Tetrax bananas and the Tetrazzi schematic again. There are 7 points per bar, one is the grey one which is connected to the wiper on one of the pots. Four of the others are the square connections on the Tetrazzi, so just two others to find.

2 Likes
#29

Holy resistors… that was a fun morning… lol

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#30

Dang man, slow down! You’re a CL paper circuit juggernaut!

2 Likes
#31

Almost to the wiring stage.
Waiting of these damn 4051’s and some piezos.

The cross and star node wiring seems like a nightmare.
Imma have to read above like 50 times over before it sinks in lolol.
This board is so big :smiley:
I found an old wooden chess/checkers/backgammon set that I plan to use for its box :smiley:

Anyone know a source for those nice black switches Peter uses?

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7 Likes
#32

Probably stated somewhere above - but all of the Cross Nodes should be the Touch Points on the Piezo bar - the Original proto had 16 brass balls connected to it with a slit drum for the piezos, there happens to be 16 cross nodes - and it looks like as mentioned above the star nodes are all of the internal connections -

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2 Likes
#33

If I recall correctly most simply: in each quadrant there are two identical stars. Connect those together and then to the same star in the next clockwise quadrant. Repeat four times.

1 Like
#34

oh - well that doesnt seem so bad - I will be able to hammer at it tomorrow since I have off :smiley:
I got everything else soldered in and the 4051’s arrived right before I headed off to work!

#35

Like this?
4 star = dark blue
3 star = light blue
2 star = purple
1 star = highlighter yellow

Touch points = highlighter green (except for the middle which are part of the mixer lol)

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2 Likes
#36

I think that’s right…it’s been a while since I had this all straight in my head at once.:crazy_face:

2 Likes
#37

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“Internal wiring” complete.
Now for 16 touch nodes, 4 buttons, output, and piezos.

Still waiting on my 4051 IC’s.
I thought they were here but it was the big 35mm piezos. lol

4 Likes
#38

That “internal wiring” is wild!
I think I might a board revision with some of this routed on the top layer, like I did for the MIDO.
Good work, I’m looking forward to the sights and sounds of the finished article.

2 Likes
#39

1 barre down… 3 to go -_- lol

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I decided to try making them similar to SHNTH barres.

5 Likes
#40

lol…

well - wired this way - the central mixer just gets hot and there is no output with a piezo wired either way -
Time to investigate…

*** EDIT *** Ignore me - I had the center Mixer IC in backwards.
However - wired this way - there seems to be no gate.

2 Likes
#41

Sorry, that stinks.
It might be take a few days but I should have some time to look at the whole thing again soon.

I think I found an error in the piezo areas: the piezo center (foil) needs to be connected to pins 3&5 of the 082s. In the paper circuit, those top traces cross but aren’t connected there either, which I think is why they got separated in the conversion.

2 Likes
#42

lol - that almost blew up my amp :smiley: lmfao

1 Like
#43

On the plus side!!!

Helps when you dont have the center IC in backwards… lol

So - it seems like it is always “on”

It is UNGODLY quiet and MUST be plugged into an amp - preferably with a preamp. lol.

The glitch points glitch the hell out of it - no vid on that yet - piezo seems to not do much - but I tried jumping it like mention above and it almost blew up my amp - however - i had the preamp boosting the ever living fuck out of it lmao. - so partially my fault -
I may play around more with what you mentioned tho -
Not sure how else to wire it - seems like there is no VCA action other than with the scroll buttons - but thats on off lol.

6 Likes
#44

Whoa this makes me want to have a terrazzi with a Low-pass gate. Guess I’m gonna patch a tetrax to the Voltage Research Lab

1 Like