On 5 Sep 2005 at 0:10, Stef Mientki wrote: > We want (well better saying my son wants) to build a propellor clock > and make a projection of the actual star map, > or in other words, "build a desktop planetarium". > > Although I like the idea, > I've the feeling that are quiet a lot large problems to overcome. > The first problem I see (or better said I don't expect to see anything ;-) > is how to get such a small spot like "a star at the sky" projected ? Hi Stef, You will use lots of LEDs. Also, have two strips of them so you have an interlaced display. You can put the two strips 180 degrees apart or next to each other as long as the timing is right. Cheerful regards, Bob -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist