Apologies to Zappa this time. The other day I bought a small LED dynamo flashlight; I was curious about the implementation details and how much power it actually generates. Turns out the dynamo appears to be a very common sort of DC motor and, while it doesn’t appear to produce a lot of power, it does seem to be a usable amount for a variety of low-power applications.
The geniuses at EMSL have managed to invent a really good kind of junk mail: The Great Internet Migratory Box Of Electronic Junk. I received one (codename: Atlanta) early this week (my week starts on Monday, so there :-P) and I honestly haven’t been this excited about electronic junk in a very long time — and believe me, that’s saying something! Briefly: one gets an email explaining the project and asking if you want to participate, if you do you receive a box of junk; you take whatever you want out, add whatever you want in, publish something about what you took out, and pass it along to someone else who will do something cool and keep the box moving. After talking myself down from replacing the contents wholesale, I picked out:
Best. Maker Faire. YET. Long lines for mediocre food? Not this year: lots of widely varied food, short lines and at least a few food Makers (which have seemed sorely lacking in past years.) A lot of cool new projects / vendors and better organized by topic / theme. The faire has grown quite a bit and the tone has changed slightly. This year was smoother and more polished than it has been; more people are selling things, but mostly in a good way. I got to make a couple necklaces with PMC, which turns out to be easy to sculpt (as expected) and easy to fire with a Little Torch (pleasant surprise!) Helped kids build Bristlebots at the EMSL booth and, as always, plugged their kits every chance I got. Found a nifty new band and played with fire (not this implementation, but same basic idea; I must build one of these!) Bought some truffle salt and, of course, hauled pinball machines, just to name a few highlights.
Apologies to Tolkien, of course! (There really is nothing too geeky for my blog, though.) This project lets you set two positions for a standard hobby servo and switch between them. It brings together most of the things I’ve learned about the AVR thus far: digital I/O, switch debouncing, analog-to-digital conversion, servo control and persistent storage in the onboard eeprom. It doesn’t currently use interrupts, but they are pretty similar to the timer that drives the servo. I built it on one of my EMSL mini dev boards so I’ve only tried the code on the ATmega168, but it should be pretty portable to other AVRs.
Yesterday morning I hit the Silicon Valley Electronics Flea Market — lots of fun, I highly recommend it. For flea market n00bs, don’t forget to bring a broad-brimmed hat, a bottle of water and a bag for loot (I forgot the first two), prices are usually negotiable and keep an open mind but not too open. I made a list and mostly stuck to it; I would’ve liked to find more of the stuff on that list, but there’s a lot of stuff there and you really have to sort the stuff you need from the cool stuff you don’t need and the utter crap or you’ll wind up being able to run your own stall 
So what did I “need”? A few pairs of hemostats, some solder wick, a set of “security” screwdriver bits, a UV LED flashlight, a pair of direct-drive moters with foam-rubber wheels, a game controller with analog sticks I can pull out and play with and a few free transistors (the solder guy has a box of free parts).
…a sheet of graph paper! I’m only half-kidding, if I had a scanner I probably would do my schematics that way. Both gEDA and EAGLE suck huge hairy balls, and not in a good way. I blame X11 and the myth of “cross platform” for many of the problems, but that doesn’t change the fact that both are incredibly painful to use. (Yes, I use a Mac, no the Mac is not perfect, but pretty much everything I use is vastly more pleasant to use than either of these apps.) Both have obtuse and inconsistent user interfaces, rampant graphical artifacting, and they’re both just plain ugly. That said, I was able to install both, work out how to draw a small scematic in each without requiring instructions, edit them to correct mistakes, and export them to PostScript (and convert that to PDF). Both meet my needs fairly well, though I’ll have to re-test both when I try to design a circuit board. Overall I’m still looking for a solution I actually like, but, despite a rocky start, gEDA seems to suck less; more detail after the jump. (more…)
Since I usually don’t take vacation time as fast as I accrue it, I’ve started taking the last friday of every month off to make progress on my current projects. These days that’s usually working on AVR microcontrollers and, now, working on this site.
Today, I reorganized my personal svn repository to the vastly superior, in my experience, top-level Trunk / Branches layout and started looking into building a usb datalogger based on the EasyLogger, though I’d like to use the EMSL board (ATmega168-based) and be able to log more than one input, but I need to either figure out if it has the right internal oscillator or get an external clock.
Just set up WordPress and already I’m banging into some remarkably rough edges: in the theme viewer, the “Test run” link invariably simply shows the default theme and attempting to narrow down the choices returns a lot of themes that fail the chosen criteria… Is this really state-of-the-art? :-/
First post! Really.