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Jim posted this email to the members email list. We'd like to see if anyone wants to take part in this hacking project. WE NEED A DATE TO DO THIS. Please let us know WHEN you'd like to work on this with us. I think it sounds like a lot of fun! Here's Jim's email: ------------------------------------- I have a nice-looking LED display in a 5"x5.5"x36" fake wood laminate over chipboard case with a smoked plexi front face. It's 7x64, with some driver TTL taking 6 bits in to select 1 of 64 columns, plus the 7 bits of row data. It's old - 20 years? - discarded I suspect because 64:1 multiplexing produces unusably low brightness. There are some more pics here. I'm looking for someone to adopt it and make good stuff happen with it for the space. I'll be delighted to help, but don't want to champion the projects. Good stuff we can get out of it: Ultimately, a cool scrolling LED display (if we can make it work). Short term, a very interesting Arduino/electronics project to play with it as is, making test patterns, etc. Short-mid term, designing and making first a test run then full set of driver boards with latches so the LEDs can be on almost all the time. Mid-mid term, assembling the driver boards to the LEDs, probably involving ~1000 solder joints. Longer-mid term, putting together some higher level hardware (Arduino?)/software to provide an accessible interface (probably serial) to make the display usable - maybe connected to our server. Depending how many people were interested in playing Arduino with it as is, we might open it up to anyone who has taken an Arduino class with us. If we had too many people, after initially getting it functioning we could split the people into 2 teams and do something like wire-ORing the row and column inputs, putting a square wave on the high column select bit, essentially splitting it into two simultaneous 7x32 displays, and hooking it to 2 Arduinos. The contest would be to make something cooler happen on your half of the display than the other guys did. Prize could be time on the Makerbot. Note that hooking it up to Arduinos as is is kind of a one-time opportunity: Once we rip up the existing wiring and start with the driver boards, that opportunity will be gone. Designing the driver boards involves designing the circuitry and laying out a fairly simple PCB. I suppose we could call the circuit design a class, but it would just be working with a couple of people who wanted to get started with a little digital electronics. I'm only a beginner with Eagle and am hardly qualified to teach a class on it, but I'd be willing to work with a small number of people to get them started with Eagle and help them design the board as a first project. The timing is probably too tight to use that as the demo boards to etch at the PCB class (the 16th?), but I'd be happy to help some folks do the board manufacture as well. Since the parts will probably be SMT, it could provide some SMT soldering practice "stuffing" the boards. (That term doesn't work nearly as well with SMT as with the old thru-hole stuff!) And since few things work right the first time, there would probably be some troubleshooting opportunities between the test board run and the full production run (of 64 boards). Final assembly will take some grunt sit-down-and-do-it work. So - anybody interested?