Since I’ve wrapped up a bunch of other projects, I had a lonely breadboard sitting around just waiting to be used. For a while, I had planned on making an Atari Punk Console, based off of Jimmie Rodgers‘ design, however, shortly before starting, I found a simple 10-step sequencer (called the Baby10). I figured in this vast series of tubes, someone else must have paired the two, and sure enough, I found several examples, but no schematics.
Unfortunately, even Christophe’s schematic was missing some parts, particularly how to setup the astable 555 timer. Luckily, between projects I thought it would be fun to go through some LED example projects on-line, and one of the ones I put together was a 10-LED chaser. It used a 555 as an astable timer and a 4017 to drive the LEDs, just like the Baby10! So with the four schematics in hand, I went to work putting pieces onto the breadboard, hoping that the mixture of differing notations (and sometimes even values) would work out for me.
It was a miracle! I had added the LEDs to Christophe’s design, as well as a switch on step 3, with accompanying diode, to allow me to run the signal back to the reset pin on the 4017, essentially allowing me to switch it from a four step sequencer to a two step sequencer. With this in mind, I began to work on a schematic for the project, one that would include eight steps and a switch on steps 2 through 8, to allow for sequences between 1 and 8 steps in length.
Initially, I had planned to include a kill switch on each step to allow me to mute any given step, but after wiring up the four step version, I realized that if you turned up the 100k pot high enough on any of the given steps, it would mute the output, essentially doing what a switch would have done anyway, so I decided to skip the switches.
Since Jimmie Rodgers already had a schematic for the APC done up in EAGLE, and since I had been doing all of my layouts in the less than desirable Visio (a great tool, don’t get me wrong, just ill fitting for schematics), I figured I’d give EAGLE a try.
Word of caution: EAGLE is not really user friendly and has a bit of a learning curve. I was able to get the schematic looking like I wanted it to look, but it probably took me the better part of a day to get really comfortable with it and I have only just begun to understand it’s nuances (and I haven’t even begun to figure out the board layout section so I can roll my own circuit boards). That being said, I’m happy with how the final schematic turned out.
My next steps are going to be getting this thing soldered up and into an enclosure. This might turn into a pretty quick project in terms of time put into it. Perhaps it’s because it’s all so well documented by other, or maybe I’m just getting better at this electronics building thing!
Since I’ve had this breadboarded and planned for such a long time, getting all the stuff soldered up and mounted into an enclosure was actually super quick. I was particularly proud of my soldering job, as it was easily the best looking job I’ve ever done.
I used the same Radio Shack 276-170 board that I have used before, and I actually ended up with a lot more empty space than I thought I was initially going to have (these shots are before I soldered up the external connections to the potentiometers and switches).
Things went together really well, granted I couldn’t get the touch contacts to work (I had planned to use rubber grommets to insulate the touch points, but after many struggles I realized that the stupid grommets were conductive! Either I’ll find some non-conductive grommets, or I’ll patch over the holes I made for the touch points with a name plate for the unit). I haven’t painted the box yet, but when I do, it’s going to be some sort of green, to match the knobs.
I know this was a short build, but trust me, the time spent planning was probably thrice as long as the build time.
Without further ado, here’s a video of the Atari Punk Sequencer in action!