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"On offer here is a PCB to build your own DIY synth based around CMOS chips, it is based on a series on the
Hackaday website by Elliot Williams, I made a few of these and had a few boards left over, last couple remaining.
It can be used to make all manner of things, examples include drum machines, drone synths, sequencers and so on, or it can just be built as a playground as intended for further prototyping, it is up to the builder. It can be built as a complete project, or just the sections you require, it can be built into a suitable case as a standalone instrument for example a drone synth, with the controls on flying wires rather than soldered directly to the PCB etc.
It goes without saying that you will need to have a fair amount of experience and the tools and parts required to build this, I would not recommend it to complete beginners. No documentation other than what is in this listing is provided, so if this is not enough then this pcb is not for you.
Parts to complete the build are not supplied, you need to source them yourself and budget for the cost of those, I think it ended up costing me about £15 in parts to build, but it depends on what components you buy and where you buy them from.
NOTE: This is purely a DIY project and I offer no technical support, search for the project page at the hackaday website (klangorium logic noise) - ebay forbids me to post the link unfortunately for some bizarre reason, which is why I had to end the previous listing with the web link.
"On offer here is a PCB to build your own DIY synth based around CMOS chips, it is based on a series on the Hackaday website by Elliot Williams, I made a few of these and had a few boards left over, last couple remaining.
It can be used to make all manner of things, examples include drum machines, drone synths, sequencers and so on, or it can just be built as a playground as intended for further prototyping, it is up to the builder. It can be built as a complete project, or just the sections you require, it can be built into a suitable case as a standalone instrument for example a drone synth, with the controls on flying wires rather than soldered directly to the PCB etc. 
