So, while you are waiting … make some music with the modules you already have and let us hear it!
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Found these in a skip:
Several 1W, 1/2W and 1/4 Watt resistors
Brand new …, well, never used … in their 30 or 40 years of existence.
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Different kind of build progress!
I’m going to have some downtime at a job site with no internet for the next little bit, so thought maybe I’ll do some learning. So, going to try to make a PCB for this layout. Never laid out a PCB before or even a schematic, so lots to learn.
Today was a bit of a surprise that I would be there so I quickly just downloaded some stuff on my laptop and was figuring it out as I go. Tonight I’m going to see if I can download some training stuff instead of just blindly poking about.
If anybody notices anything glaringly wrong in the schematic let me know! Ignore the PCB layout, just putting stuff around with no real rhyme or reason for now to see how the software works, will do reading on best practices tonight.
With 0 knowledge going in, I think it was a good day!
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You have an error in that you are using +12V for both a global label and a power flag, and KiCad will assign those both the same net so pcbnew will want you to connect them together. (Ditto with -12V.) My preference, and it’s what I usually see in others’ schematics, is to use the +12V and -12V power flags where you have the global labels, and then use a net label like “+12V_IN” where you have the power flag. There’s no actual problem with the GND global labels but it’d be preferable to use the GND power flag instead.
Don’t see any other obvious errors though I didn’t spend much time comparing against the stripboard layout.
Ahh I think that makes sense, thank you!
I was using another design as a reference and thought this was how they were doing it but must have misunderstood it. I showed it to a couple other people and they all thought the power section looked weird as well.
Thanks again - if I run into any major issues and need help I’ll post a new thread so I don’t clog up here
Also, you have a 100k output impedance, which is way too high. The output will not be able to properly drive the input of another module, as the input impedance is also typically 100k. I’d suggest you change it to max 1k. Cheers!
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I think you’re referring to R5? If so, good catch - original layout has it as 100 ohms, I mistyped it when putting it in. Thanks!
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Yess, that’ll fix it!
Update: just an addition to the power flag/global label talk. Right now you have the +/-12V labels connected behind your reverse polarity protection diodes, but the power flags before them. I agree with @analogoutput on using only power flags for the power nets, and make sure you connect them only behind your protection circuitry. Cheers!
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Here’s how I did my last power header:
It’s for a 16 pin header, but the principles are the same for the 10 pin version
Note the funny little diamonds - they flag to KiCad that these are power nets, so now you can use the +12V and -12V power symbols wherever you want in your design. You no longer rely on a global label, like V_FC_KB in the example - which I reserve for signals. Now when you run the ERC (which I recommend you do early and often) you won’t get messages about these power pins missing a driver.
You also might want to double check that you’ve got the pin ordering right on the pin header and it aligns with your expectations of the footprint in pcbnew.
Cheers
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So I think it’s time to post a WIP shot of this:
ESun PLA+ orange on point, mostly because that was already loaded into the printer. Thanks to whoever posted the flexrail link somewhere around here.
I started building a traditional linear supply but I feel it is just going to end up too big for a small 32hp pod. But I’ve figured out that some of the cheap DC-DC converters will create a negative rail if wired creatively!
Current modules are passive mult and dual passive lpg (still missing a toggle switch).
Planned modules:
Pt2399 module delay inspired by nlc
Joystick module
LFO (icl8038 based)
sequencer, maybe cd4017?
This pod is to support my bARP2600 hence lack of filters and vco’s
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FWIW, your example here has the pin numbering reversed. Pin 1 on the IDC header corresponds with -12V.
Yeah - totally agree - I think it comes from using pin-header footprints instead of IDC footprints, or something like that. In any case - “red stripe down” is burnt into my memory, and this way the schematic more or less physically matches the layout’s footprint.
2001 done more or less.
I even paid a shop for some timber battens on Sunday to make the rails for my “Final” case. Usualy I grab whatever scrap I have and coble something together, but that usually is a pain and things don’t work out.
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100R is too small. If the op amp’s putting out 12 V and the output gets shorted to ground the power is V^2/R = 1.44 W which is way more than the resistor you’re likely to use can dissipate. 1k is a typical value.
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You can always rotate the symbol so pin 1 is at the bottom, I do that all the time. (Or rather I did that once for the template file I always use.)
(In case anyone’s wondering why there isn’t a PWR_FLAG on the ground rail, it’s because I defined my Synth_power_2x5 symbol to have three power output pins, one each for ±12 V and GND. Since the ±12 V rails connect to the diodes rather than directly to the header, they still need PWR_FLAGs, but the ground doesn’t.)
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Thanks for the help guys! You’re all fantastic!
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good luck. its fun getting your own PCB’s… Not so fun when you realise a fault and have to re-order but it helps the learning process 
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Thank you!
I might not even print this one or maybe any at all at the end of it. I already have a working stripboard module of this with no need for another, nevertheless five of them for a minimum PCB order, but it’s a relatively small and easy circuit so I thought it would be a good one to learn on and see how it goes. After I get the swing of things I’ll see if this is something I enjoy doing and want to branch out to try something thats not already in my rack and I need, or if I find that it’s a chore and not something I like spending time on I’ll stick to prefabbed / ready to order PCBs and stripboards.
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Today i decided to mod my Dual CV Glide, i’ve add a CV with a vactrol on it but now i don’t find it usefull.
Instead with the holes i add the Rise/Rise Fall / Fall switch and also another switch for select long or short glide (1 or 10 uf MCC).
before
after
I used this diagram
so I also added some cap (power & decoupling) and also some resistors on the input and output sockets
i try it and all is ok
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Well you’re right there. I’ve got a bad habit of being more of a builder than a player.
And my wife loves it when she can steer that urge into home improvement projects.
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