Workspace

Ultrasonic Doppler Flow Detector

My first "real" electronics project, this is a Nic Collins design on a 74HC14 chip - 5 oscillators, 4 of which are available via knobs. I'm going to write a lot more about this later.

EDIT:
This is 5 oscillators on a 74HC14 digital logic chip. Four of the knobs control individual oscillators --the 5th knob is interesting because it allows you to choose between two signal groups - one of which includes all the oscillators going, and one is just a few oscillators. It has a built in speaker, which is amplified from a 386 audio amplifier, and a 1/4" out. The fun thing is that the oscillators sort of cross-modulate each other, I assume because of limited power supply - they cannibalize each other's and ending up dirtying up the signal, which is great for me. I'm going to post some tracks that I've made with this box soon too.

AUDIO LINK: http://www.hotlinkfiles.com/files/416916_in5s9/ultrasonicdoppler.mp3

Repackaging and Controlling

These are my first two attempts at repackaging toys, both from over a year ago. I've gotten a little better at it (see the previous post on PINK BOX), but I really like the messy, science fair project-gone-wrong feel these things have to them. This one in the grey box was also my first experiment with building my own controllers - I tore open a calculator, traced lines on the circuit board myself to find pin connections, and used the buttons to control various functions on a toy guitar (notes, pitch, distortion, etc) that I found while bending it. An interesting result was that different button combinations would create very different levels of resistance, and would be completely different than pressing the buttons independently. Another interesting effect of this is that the calculator interface would allow certain buttons to be activated only when other ones were pressed down -- which I never really analyzed, making for a chaotic and interesting interface.


EDIT: Sound link for this thing now available:
http://www.hotlinkfiles.com/files/416921_vlwf3/superbox.mp3

This second project was built into a small dumpstered typewriter case, and was an experiment to indulge my fetishization of patch bays, and using circuit bent voltage signals to process other toys. It's made from the insides of 4 independent toys - an Elmo toy, a "bomb box" that made explosion sounds, a telephone toy, and a steering wheel toy. The patch bay allows you to interconnect their signals, and wasn't a total success. I really wanted to have the audio output of different toys be the control voltage to modulate each other's pitches, in some sort of weird feedback loop that I could patch between. Unfortunately, an audio signal doesn't do the job very well -- if I were to rebuild this today, I would use LED/photoresistor (also known as vactrol) combos to patch between instead of just straight electricity, but I'm not going to go back and fix it now.

Blog notes

If you haven't already discovered Google Reader , it's the best way to read my blog: just type in futureeelectrode.blogspot.com and you're all set.

Also, I removed some of the sound samples from earlier posts because I only have 20MB on my wesleyan web world, if someone knows how to get better free file storage that's not RapidShare or the like, email me.

Music Maker Keyboard

This is a typical black-blob type chip, but it seems to do some sort of fake synthesis, because connecting the pins results in many different alterations to notes, including modifying sustain, attack, volume, envelope shape (sort of), and of course, a pitch shift. I decided the best way to use this would be through body contacts, and it came out alright.

http://boconnell.web.wesleyan.edu/musicmaker.mp3

PINK BOX

Sounds:

http://boconnell.web.wesleyan.edu/pinkbox.mp3

Apparently means something to some people - it's a toy I re-housed in a pink plastic box. The plastic was messy to drill through - it's the really hard kind that cracks extremely easily. The original toy was a microphone with "sound effects" such as people booing (represented in typical Engrish fashion by a ghost), applause, laughter, etc. I found an internal pitch shift, as well as another slightly different one accessed through a voltage drop.

I really like these toys that are built with overpowerful amplifiers, so the microphone feeds back when you bring it even slightly close to the speaker, which then slows down everything else the toy is doing by virtue of sheer mismanaged power usage.