Homebrew Printed Circuit Boards
What Where When
We met at Noisebridge on Saturday, July 25th at 3pm and designed some circuit boards.
We planned to follow a procedure not unlike this:
Saturday, July 25th, 2009
We ended up spending most of the time just designing the circuit. We based it on the Noisebridge logo, incorporating a series of resistors, a speaker, and for fun, an ATTiny25, an LED, and a micro switch. It's powered by a coin-cell, located on the back of the board. It can be programmed to do things! Look! Here's the Eagle CAD schematic, the Eagle board layout, or, if you don't have Eagle, a PDF.
There are a few ideas floating around for how the ATTiny25 can be programmed. One is for the LED to always be on, and for the speaker to make noise when the center button is pressed. It has also been suggested that the speaker play a song (London Bridges Falling Down?).
We then tried transferring it to a solid copper board by printing onto magazine paper and then ironing that onto the board (we lacked the proper transfer film). This sorta worked, but not good enough. We subsequently learned that the magazine paper method works best if, after the paper is ironed to the copper, one wets the magazine with soapy water, loosening the fibers and leaving more toner stuck as you pull the paper off.
Monday, July 27, 2009
Skory got some supposed transfer transparencies at Fry's (they're now somewhere at NB if anyone else wants to try using one). MCT used up a couple minutes of company time, toner, and coffee getting one the sheets printed on. Not without some mishaps, the deed was done - success was achieved.
Without further ado, a pictorial account: