This was a sharpening-my-tools week. Figuratively, not literally.

I gots me one of these, and I gots me one of these. That last URL in particular looks a bit hinky, and anyway you may not care about the data sheets, but they're both development boards. The first one is a board by TI that has three 16-channel LED controllers, each hooked up to the red, green, or blue segment of a tricolor LED. The second one is an FPGA (Field Programmable Gate Array) board--it's a reprogrammable chip like a CPU, but it's programmed at a much lower level. It's kind of like one of those radio shack 300-in-1 educational toys, except the wires are really transistors, and you don't have to tweak them by hand. Put 'em together and it looks sorta like this:

My outgoing email had gotten really slow. Turns out that was due to all the bounce messages sent in response to spam for invalid addresses at my domain.

I've been driving around for the past couple weeks with a carload of used bricks salvaged (with permission) from the former site of a recently moved house near my friend Kerri's house. For the past week I've had a bunch of "used" irises (which Anne says looked like mandrake fetishes) in my yard awaiting planting. I got them from a neighbor whom I ran across during a walk with Naj. Yesterday and today I put the two together into a planter for my front steps. Wheee!

Crappy cameraphone pictures follow

The charger for my digital camera has gone AWOL, so no pictures on this one. I'd had a four post equipment rack (kinda like this one) that I'd intended to put in my basement, but which turned out to be too tall. It sat in my yard on its side for a couple of years until my friend Naj suggested I use it as a planter for vine peas. So, this week I did just that.

(Yes, technically it's not Friday in my timezone anymore, so we'll either pretend I'm in Hawaii, or that the deadline is "before I go to sleep after waking up on Friday")

Acoustic beamforming is a technique for operating an array of speakers or microphones in concert to "steer" a virtual beam of emission or detection with much tighter directionality than is possible using a single element. You can use it to make a highly directional "cone of sound" which you can point in different directions, or to pick up a localized sound source amidst lots of background noise. It's possible to build speakers and microphones with narrow emission or pickup patterns, of course, but beamforming allows you to use less complicated transceivers, as well as changing the field pattern dynamically. (This actually works for electromagnetic waves too, but I'm looking at sound waves for the time being.) This week I took a look at the theory behind it, and performed some numerical simulations.

Week 1: Synthetic Holography

This week I played with lasers, both printers and pointers.

For a while now I've been thinking I've been kicking an insufficient amount of ass. I have all sorts of ideas for wacky, pointless, and/or over-engineered WhatNots, but usually I do an initial burst of planning and then things sort of peter out.

No Longer!

With apologies to Jonathan Coulton for shamelessly ganking the name "Thing-A-Week", Project My-Own-Personal-Thing-A-Week means that starting June 1st, 2007, each Friday for the next year I will post the specifics of some sort of projecty thing that I've made over the previous week. I have only the vaguest idea of what sorts of projects. A while back I tried making Bismuth crystals, so I'll probably start out recycling that one by doing it again. Maybe it will be electronicsy, maybe computery, maybe close-up pictures of funny little bugs I find in the garden, maybe stupid lego tricks, maybe crappy abstract art, who knows?

This is absurdly ambitious, so much so that I was prepared to give up on the idea since it seemed so very, very likely I wouldn't keep it up. As soon as I caught myself thinking "you'll probably fail, so why bother trying" I realized I absolutely had to do it.

Step one, of course, is making an ostentatious and public declaration of intent, so that I have fear of never living this down to keep me motivated.

I don't have any particular expectation that people will find any particular project interesting, but you never know. Anybody who wants to pitch me an idea, lend assistance, or help me make a Science Helmet(tm) is quite welcome to do so.