555 Keyboard

I've been planning this doo-hickey for a while now, and this morning I finally started it. It's nothing too special, just an 8 note keyboard built from a bastardized optical theremin. I added 8 N.O. pushbuttons with 4.7K resistors in between. They're wired in series which makes this thing monophonic. Here's the heart of the circuit all soldered up:

I still have a little bit of work to do on this. I'm adding a vactrol and an LM324 filter. I'll upload video and photos of everything when it's all done, so stay tuned to this blog.

Update 7-9-2011:
Have yet to add the filter or vactrol, but the damn thing died on me somehow trying to cram it into the case. Updates on this may be lacking due to the fact that I might have to build the entire thing over again. Damn.

Update a few hours later:
It's alive! It's aliiive!!

Update 7-11-2011:
Still kickin'. Installed the LM324 filter, and it sounds amazing. Not what I was expecting it to sound like (different from when I prototyped it, hmmm), but I think it sounds better. Right now it's housed in a small alarm clock case, but since I need more room, I'm transferring the circuits into a sturdier (and bigger) project box.

 I still need to add the LFO/Vactrol to the circuit. I'll end up doing that mess tomorrow. After that, all I need to do is put everything in the new enclosure and presto, it'll be done. Videos and photos will be posted tomorrow I hope.