I want to share my project I am working on for some time. I designed and created first time so large wood project not having best tools. So, finish is not perfect, but it feels solid and have this rusty, long time used and forgotten, style.
Goal to create portable eurorack case for 2x120hp and keys is achieved. I used 3-layers plywood and mixture of vinegar and old steel screws to age the wood. On the back is small plate on hinge and burr that make all stable when is opened.
As you can see I have some poorly-formed rails with nuts. Yo know the cost of traditional eurorack rails, I paid for 3m of this, used in advert business, including nuts, less than 5$. Now I will probably just go with the wood and screws, but here it is - works, i tested it in first module that is modified delay from Ali. Plate for module is made from old beige PC case that first time came pretty harcore-industrial looking : )
I am going to use as a keys Casio SA-20 that I will curcuit-bend and cut the speakers off. That will make me place to add drum machine I think about - DrumKid on Arduino. Top part for DIY modules, there i plenty of space for experiments.
If you have any questions feel free to ask, I will do my best that you can use my experience before you start design and making your own.
As I posted now the picture - only mod of module from Aliexpress made for echo/delay.
I am experimenting with capacitors values for LMNC SSO and burned some NE555 trying to make APC : )
I hope Sam will upload scheme of improved SSO, I will take look on that and make module basing on improved module.
Do you have experience with the converters used in this project? Won’t they introduce unwanted high frequency noise (they are switched mode devices)?
They were recommended me by other forum user as easy, simple and reliable way to deliver power. I can make measurements you want to know when I mount them.
The LM2596 operates at 150 kHz ±15%, which may or may not be a problem, depending on module (it’ll usually get filtered out). But I’d be more concerned that the design appears to rely on the exact schematics used by some subset of all the chinese manufacturers of the converters you’ll find on ebay/aliexpress; while the IC can produce a negative output if wired up correctly, the regulator boards you get off the internet aren’t explicitly designed for that, and you have no idea what you’re buying (and neither has the seller). But I guess it falls in the category “if it works, it works”
UPDATE2 : I was told (thanks fg) that only LM2596-ADJ jm88rp, jm74rp or jm84rphs works. hw411 board with LM2596-ADJ jm97rphs don’t works. So I did not recommend using this schematics anymore. I keep this page online only for archive.
So I guess I need another design, I see only hw411 on Ali. Do you reccomend any cheap and easy using old laptop power supply?
The frequency central supplies mentioned there expect 12 V AC, not DC. Creating ±12 V from laptop supplies is non-trivial; you need robust DC/DC converters, and the result still isn’t necessarily great (see the discussion of switched supplies in that thread for why). There are some designs out there that use industry standard converters to go from DC to ±DC, e.g the D112 that was discussed here, but at that point it might be easier (and cheaper) to use e.g. an RT-65B supply.
But I’d suggest taking the power supply discussion to that topic, to get more eyeballs on it.
