I needed some small boards to put an ATtiny85 on, so I drew up a simple board in Fritzing and had them made up at OSH Park.
Here’s the breadboard view in Fritzing. Whenever I need “holes” to solder random components into I just use screw terminals. I’m sure there’s another/better way, but I’ve not found it yet, so I keep doing it this way.
Once the breadboard view is done, I go to the PCB view and move things around, make all the connections, and then export the files in Gerber format. Once you have a folder of Gerber files, you can ZIP it up and then upload to OSH Park for fabrication. (I covered this process in a previous post.)
I did find this Mac OS X application called MCN Gerber Viewer which allows you to view Gerber files. You can view the different “layers” and turn them on and off to check your board before fabrication. OSH Park shows you what your board will look like when you upload it, so you can easily check for issues, but MCN Gerber Viewer is still handy to have around to check files before you upload them.
Occasionally I show up at Milwaukee Makerspace with no clear idea of what might happen when I’m there. This piece, titled “Click Whir Squee” is the result of one such visit. Another member brought in a box of old computer hardware, including a Hewlett Packard Colorado T100E Tape Backup Drive. Being a fan of old technology (1997 is old, right?) I opened up the drive to take a look inside. I also powered it on and stuck a tape in it. The drive came to life and unspooled the tape and made a lot of spinning motor and tape loading sounds. Not everyone knows what these things sound like. It brought back some memories. (At my first job in the tech industry I had to load daily backup tapes into two tape drives. I remember the sound fondly.)
I somehow decided I should mount the tape drive to a piece of wood for display, so I went to the Wood Shop and started cutting up some scrap wood I found. Steve showed up to do some training, so I sat in on that for a bit so I could use the compound miter saw and the band saw. I had all the pieces cut by the end of the evening and knew how I was going to mount it.
I ended up taking all the pieces home and assembling it in my basement workshop. I manage to only split one piece of wood. Just a minor split, but a reminder to slow down when working with wood. The rest of the assembly went very smooth.
Since the majority of fun with this drive is the startup sequence, I decided it should continually turn on, do its thing, then turn off, and keep repeating that. I’ve been playing with ATtiny85 chips lately, so I put one into service to trigger a 5 volt relay (which I also grabbed from Milwaukee Makerspace) and put the following Arduino code on it.
Yes, this is pretty much a glorified blink sketch. Sometimes the simplest things are exactly what you need. (Astute readers will see that the device will be on for 70 seconds, and then off for 15 seconds, and repeat indefinitely.)
To power the ATtiny85 and the relay I found a Samsung phone charger on the Hack Rack at Milwaukee Makerspace. It even had a long cord, which was quite useful. You can also see one of the tapes that this machine uses. Now, if you really want to find some contrasts, consider that the modern day phone charger pictured here was used to charge a phone that probably had 8GB (or more) of solid state storage. The tape next to it could store 400MB of data (or 800MB of compressed data.) I should have included a MicroSD card which can store 8GB of data that I routinely buy for about $6 USD.
Since I removed the case there was no indication of what this thing was. I felt I should have something that told a bit of the story. I chose to mount the beige power pack, with “Hewlett Packard” emblazoned on it prominently.
Oh, and while the whir of the motor is quite satisfying, we can do better. There is a wooden arm to which you can affix a small piece of material with a binder clip, which will then be activated when the primary motor spins. Fans of baseball cards and bicycle spokes, this one is for you! I call the “Annoy-o-tron” mode. (Look, if you’re going to use an ATtiny in an Annoy-o-tron, at least be original, right?) I’ve experimented with paper, vinyl, and plastic, but finally settled on a piece from an anti-static bag which some electronics were shipped to me in. It seemed fitting.
Gallery owners and curators take note! This piece is ready to be mounted to a wall, and needs just two outlets to power it. It’s pretty much guaranteed to amuse some visitors while annoying other visitors. Art isn’t always about being pretty.
Enjoy the video below which allows you to experience this wonderful piece over the Internet while in the comfort of your own home (probably while wearing pajamas.)