x5 WAY MIDI THRU BOX
This is a great little one-day project that can be pretty useful if you control your instruments over MIDI. Basically this box allows you to send 5 different MIDI signals over 1 output. So you can have a PC with 5 midi tracks, send it over 1 midi output to this box where the signal is then split into 5 outs, which you can then plug in 5 synths and have them all play nicely together.
There are better descriptions on the internet I'm sure.
I found the original schematic here on the highly liquid forums;
I made a couple of small changes to the schematic; instead of running it from the mains I figured it was low power enough to run it from a 9v battery, so from there I added an on/off switch, and to be fully sure I didn't leave the battery on, I also added a red LED.
To get it all to fit onto one breadboard I first drew out the schematic onto some graph paper. This was my 3rd attempt and I'm sure you could have a more efficient design, but this was good enough for me and I guess it maybe of some help to somebody else out there;
The plastic enclosure/project box came from Conrad for €3.09;
Here the on/off switch and LED can be seen;
Cable ties make everything look neater;