Cassady's Not Terribly Fantastic Website -

Solar Panel

autarchex — Tue, 15 Jan 2008 07:38:36 +0000

I used individual polycrystalline silicon solar cells purchased from Electronic Goldmine. Each cell is rated .5V, 1.0A. Of course, that's somewhat optimistic...

Transistor as LED

autarchex — Tue, 15 Jan 2008 07:14:33 +0000

I remember seeing somewhere on the Internet (EDIT - I saw it here) that it is possible to produce light from a power transistor junction. As I am all for abusing electronics, I set out to replicate this behavior. I chose for my victim a 2N3055 power NPN in TO-3 case. To get at the junction inside I cut open the case with a dremel and cutting wheel:

Capacitor Six-Pack

autarchex — Tue, 15 Jan 2008 06:46:12 +0000

I pulled this out of a storage box under my workbench recently. It is a six-pack, but it is not beer. I remember building it, but I couldn't immediately remember what it was for. It looks cool though. And menacing. Mostly, it just looks like it wants to kill me. This bank is 0.186 Farads, 50 V. The bus bars are made from thick copper wire beaten flat with a hammer. In the images you can see that I've hooked it up again. It's fun to play around with, and vaporize little bits of thin wire.

Bookdrive

root — Sat, 04 Nov 2006 07:00:00 +0000

In this fun but somewhat impractical extension of the tried-and-true booksafe, I sought to embed a USB flashROM drive and a USB mini-B connector into an innocuous-looking book, such that the book could be connected to a computer and used for data storage just like a flashdrive. Why impractical? It did occur to me while making this that the traditional booksafe, which is simply a book with a hollowed-out cavity inside, could simply be used to conceal a flashdrive. Nonetheless, I liked the idea of making a book with a data port.

Hard Drive Stereo

autarchex — Mon, 22 May 2006 07:00:00 +0000

Some time ago I turned a hard disk drive into a speaker, inspired by articles on the internet, all of which seem to be traceable to The Afrotech Hard-disk Sound System. But why stop at one speaker? Just because I'm willing to put up with the scratchy, jittery sound of a new hard drive low-fi system, that doesn't mean I'm willing to give up the novelty of stereophonic sound!

Lessons Learned: My first PCB

autarchex — Mon, 22 May 2006 07:00:00 +0000

I've been meaning to try my hand at PCB layout for a while now, but none of my projects ever really required it. My group's senior design project (a demonstration model of a reconfigurable IC tester to assist in radiation-validation of new ASICs) didn't really require it either, but we felt that putting our system on a PCB would make it look more professional (it was previously distributed over a handful of dead-bugged copper clad sheets connected by a dozen poorly made cables). Also, sloppy construction was suspected to be the reason why our RS-232 connection between system and host computer was only transmitting about 70% of bytes correctly, so there was some hope that a PCB would solve this problem. It did. To skip ahead a bit, it was

Hard Drive Audio

autarchex — Sat, 22 Apr 2006 07:00:00 +0000

A hard drive can be modified to produce sound and play music like an incredibly crappy speaker.

Long-term Memory

autarchex — Fri, 21 Apr 2006 07:00:00 +0000

I realized some time ago that 90% of the stuff learned in a college course is forgotten within two to three months after the final exam. I find this especially troubling because I went into debt to the federal education loan program up to my eyeballs in order to learn all that stuff. In an effort to hang onto it, I started keeping a running summary of my classes in a durable leather-bound journal (made by Hippo Leather Products) that I picked up at the Oregon Country Fair one year. At the end of each term I try to set aside several hours of time to sit down with all of my notes, organize and condense them, and put them down on paper in a concise and well-ordered fashion.

Early Rocket Fuel Trials

autarchex — Fri, 21 Apr 2006 07:00:00 +0000

My roommate and I occasionally try our hand at making a homemade solid rocket fuel that is easy to make, safe, and stable. So far we have yet to get all three traits. Recently I ran across some old photos of one of our earliest attempts. I have no recorded data from this night, but it appears we were making sugar-nitrate fuel. This looks to be from before I tried powdering the ingredients and mixing with water to form a paste which could then be dried into a desired shape - these photos suggest we were still melting the components together (very carefully on an electric stove).

Serial Pic Programmer, revised

autarchex — Wed, 05 Apr 2006 07:00:00 +0000

This is an updated version of my previous programmer. Refer to the original for more depth.