When I built the KosmoNought case I was pleased with a job well done, but I knew that I had to get something inside it to get that real feeling of having started the project. Now the first piece of electronics has arrived in the form of a Mean Well RT-65B power supply.

This is a 3-rail supply providing +5 VDC at 5.0A, +12 VDC at 2.8A, and -12 VDC at 0.5A. Most modular synths run of either +/- 12 V or +/- 15 V. I opted for the extra 5 V rail because I plan to make some modules based on either Arduinos or ESP32 microcontrollers, which require 5 V. They generally regulate that down to 3.3 V, but that’s done on board so I don’t need to provide that. The modules I had in mind that will use the microcontrollers are tuners for the oscillators, and sequencer/drum machines. For digital electronics, the 5 V line needs to be within a fairly close tolerance and this PSU has an adjustment potentiometer to get it set right.

The PSU turned out to be a lot smaller than I expected, which is good because it won’t occupy too much space in the case.

One thing I found a little annoying about the PSU is that there is no protective cover for the mains terminals. They are available, but cost an additional £6.50 or so + postage, which I thought was a bit steep for a small bit of plastic. Not to worry though. I have a 3D printer which is itching to get working on something. I’ll get designing and printing and if it all works out, I might even make a load more to sell to other users of the same PSU.

I would really have preferred it if the PSU had spade connectors for the mains. I have some adapters that convert screw terminals to spade connectors, but they are too wide for the screw terminals on the PSU.

Next job will be fitting the PSU to the case. It needs to be safely wired to an IEC mains socket and switch via a panel-mounted fuse, so it’s not just a case of screwing it in to the case and connecting some wires. All exposed live terminals will be covered in heat-shrink tubing for safety.

The PSU is readily available from many places including Amazon. If you buy through this link I will receive a small commission, but it won’t cost you any extra. Doing this really helps me out and all commissions earned will go towards the production of this blog and may also get me started on a YouTube channel, too.