Are these wooden and made with a CNC-machine?
As I mentioned before, this is just a mockup with connected traces, I will definitely adjust the traces.
Not sure I understand you, what mounting holes? They will be mounted to heatsink, or do you mean that heatsink doesnāt have mounting holes?
Thank you for the advice, I was sure that 10pin IDC cable can handle 0.7-1.5 A, depending on the plastic/wire used.
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Theyāre 3d printed. The last step will be to use some white paint on the inlayed letters and clean it up with a damp paper towel.
Iāve made panels for 6 frequency central White Faces and a stasis leak. I also made alternate panels for Samās ADSR kits so I can do sliders instead of rotary pots.
Right now Iām experimenting with printing some brackets to hold the PCBs vertically in my case, and wire them to to panel components with spade and molex connectors.
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I use those, the FC boards have pads that will work and my bus boards have footprints for them.
In fact, they can be used with a pin header footprint. The 5 mm pin spacing is close enough to 0.2" that it can go in.
WĆ¼rth cable is rated 1A:
https://www.mouser.com/datasheet/2/445/63911015521CAB-1718414.pdf
It doesnāt say specifically whether thatās per conductor or total, but the 20 conductor datasheet says the same thing so presumably itās per conductor. So 2A on each of the Ā±12V rails assuming no one got lazy and failed to solder all the pins. Iād think that should depend on the cable length but not according to the datasheet.
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Additionally, the multiplexer chips im driving here look like they are drawing very little juice. Which is good since the plan is to have this USB powered, and USB 2.0 specification is rated at 0.5A. We can get higher amps with 3.0 (0.9A), or dedicated charging ports (1.5A). I have not checked the power draw for a fully loaded system here, but i am hopeful. I will also of course have to be mindful of the current drops that will occur across these cables, but i can test that here at home.
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Almost certainly not an issue with your system. I understood @eric to be talking about using terminal blocks vs. ribbon cables (as on @Rustyās design) to connect PSUs to bus boards.
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Yes, my reply was a direct reply to @Rusty 's post.
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Well thanks yāall. I donāt doubt that i could be making some mistakes here, and if i was i would appreciate that before i spend money on the design.
Its good to hear that its probably not an issue though.
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I added the CHARM to my fourses - played around with some rollz - this switching insanely fast - and all of a sudden - AM radio signalsā¦ lol
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Iāve had only limited success with text in my 3D prints. Would you be willing to share an STL-file so that I can see have a try?
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Sure. Iāll make some sharable links when I get home.
Iām using inkscape to make vector files, and then I import the drawings into 123design to make the STLs. Both programs are free and pretty user friendly.
For the printing Iāve tried a few different waysā¦ At first I was prining them face down to avoid using any supports around the stiffening brackets, but I had a lot of trouble with the little details in the lettering not sticking to the bed.
So now I print them face up with ironing turned on. I used harder PETG plastic and then put a texture on them with my sandblasting cabinet.
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I shared my work folder to give you an idea of what Iām doing. I start with .svgās in Inscape. Sizes.svg is a template with all the right sized holes for the components Iām using. From there I make 2 .svgās for the holes, and for the text and import them into 123design.
From there I use the extrude tool to give it thickness. I make ācookie cuttersā out of the text .svgās, and then use the subtract tool to make the inlayed letters.
The .123dx files are 123designās proprietary files, and from that program I export .stlās my printerās slicer can understand.
Itās far from the quickest way; if you need to make changes it means redoing a lot of stuff, but I think its pretty good for all free software, and a guy just puttering around in his spare time.
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Many thanks for sharing.
Whatās that DIN connector for?
I was assuming MIDI, but the two resistors donāt seem to be the right value for MIDI out and there is no opto-coupler for MIDI in.
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It is midi out.
From what I was reading, the normal 2x 220 ohm resistors for 5v are wrong for 3.3v. Since the supply voltage from the teensy 3.2 is 3.3v. I am just working from MIDI spec. Since this is only midi output, an opto-isolator is not required I donāt think.
I have only implemented the MIDI DIN for MIDI out with an arduino nano. In that setup, I simply used the two 220 ohm resistors.
From the MIDI V1.1 Electrical Specification:
One thing i havenāt included is a switch to select either the serial MIDI or USB MIDI interface.
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Wow, I didnāt realize the forward voltage drop in opto-couplers was that high. I learned something today.
Why not just transmit on both?
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Iād be very interested to see how you switch between USB and DIN. Any examples would be useful.
Iāve built 2 boxes (string synths) and USB option would be useful.
An ideal scenario would be to control directly with a small USB controller (like an Akai) but I guess that would complicate things.
Any advice gratefully received.
@antoine.pasde2 The simple answer is that I could, but that would also potentially increase the runtime managing both interfaces. So yeah, good point I might not even bother.
@Farabide I fully intend on continuing to expand the WIKI. This project is consuming a lot of my time right now, but I plan on detailing a full how to along with the release of these PCBs. The WIKI of course will not be written in any way that you would need to use them, but from my experience, I think it will make this whole process much more simple. This is still very much a DIY endeavor.
TLDR; you would use a digital input pin with a toggle switch that can set a flag for use with conditionals in the program to trip either initializing a serial interface, or an interface with USB. Any changes would need a reset of the device (unplug and plug back in works fine).
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Oh, I have 2 little things that I did that I can show you. First, I got a phaser effect pedal and converted it to a 3.5mm jack plug. Unfortunately there must always be a 6.35mm dummy plug in the input socket, otherwise it wonāt work.
And then I gave my Volca sample a midi out socket.
Unfortunately, I didnāt have a suitable drill, so I had to do the rest with sandpaper, so the socket is a bit too deep ā¦
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