[Bill Porter] continues finding ways to help out at the local museum. This time he’s plying his skills to fix a twenty-year-old exhibit that has been broken for some time. It’s a laser spirograph which had some parts way past their life expectancy.
He started by removing all of the electronics from the cabinet for further study in his lair. He examined the signal generator which when scoped seemed to be putting out some very nice sine waves as it should. From there he moved on to the galvos which tested way off of spec and turned out to be the offending elements.
A bit of searching around the interwebs and [Bill] figured out an upgrade plan for the older parts. But since he was at it, why not add some features at the same time? He rolled in a port so that just a bit of additional circuitry added later will allow shapes and logos to be drawn on the screen. One of his inspirations for this functionality came from another DIY laser projector project.
Take a look at the results of the repair process in the clip after the break.
[youtube=http://www.youtube.com/watch?v=t4ggH4i4LKo&w=470]
“We control the horizontal, we control the vertical…”, mabye when this thing needs to be fixed in another 20 years the hacker to do it will have been inspired to have gotten into hacking by playing with this thing in the first place. Nice job!
Nice job on the repair.
Forgive me for pointing out that, despite it’s name, the exhibit is not a spirograph. The images are Bowditch curves (a.k.a. Lissajous figures), not hypo- or epi-trochoids.
You will have to take that up with the original creator Ken.
I know where this is! This is in the Pacific Science Center in Seattle, Washington. I knew the exhibit looked different…
Actually, this particular one is in Florida. Though this was a popular exhibit and there are many copies across the US.