Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!asuvax!mcdphx!citek.mcdphx.mot.com!hbg6 From: hbg6@citek.mcdphx.mot.com Newsgroups: sci.electronics Subject: Re:sequencer... Message-ID: <14182@mcdphx.phx.mcd.mot.com> Date: 5 Dec 90 03:10:57 GMT Sender: listen@mcdphx.phx.mcd.mot.com Reply-To: hbg6@citek.mcdphx.mot.com Organization: Motorola Microcomputer Division, Tempe, Az. Lines: 24 Summary: Expires: References:<2047@mountn.dec.com> Sender: Followup-To: Distribution: In article <2047@mountn.dec.com> hutzley@bigq.dec.com (Steve Hutzley) writes: > > I'm sure by now, that everyone has seen the christmas lights that CHASE > > I know this can be done with TTL, driven with something like a 555. > but have been unable to make it work. I have one of those "light in > > Anyone want to help in this venture? The system I put together uses a 555 set up as a .1 to 1 Hz variable oscillator. The 555 output feeds a garden variety BCD counter. The four bits of output from the counter feed a BCD to 1-of-10 decoder. Decoder 0,1,2 and 3 all feed seperate solid state relays. These relays switch 110vac to four seperate strings of christmas lights. The decoder output number 5 feeds the reset pin on the counter. ( I think I had to invert that signal...can't remember) The hardest part of the project was making the light string. Line up all four strings so that the bulbs, taken in sequence, come from different strings i.e. 1-2-3-4-1-2-3-4-1-2-3-4-1-2... The cable tie after every fourth light. It's a lot tougher than it sounds. good luck John Oh, as long as I'm here..... 74LS445 = BCD to decimal decoder / driver Brought to you by Super Global Mega Corp .com