gurney@kira.msu.edu (Eddy J. Gurney) (11/02/90)
I just got done reading the latest issue of Radio-Electronics. Or at
least part of it. :-) There's an article in the December issue on building
a "Christmas card" that has 50 LEDs that blink in response to an AGC'd
microphone audio input. The article explains that they're really just
"bar drivers", driven in either dor or bad mode, depending on the singal
level.
Great. Sounds like it could be interesting. BUT...
I'm sure everyone has seen those "Light In Motion" 140-light sets that
appear to "move" by blinking the four different color lights in sequence.
I have such a string, and after reading the article, had this great
idea: How hard would it be to use a similar audio filter and instead of
lighting a bunch of LEDs, turn on one of the four groups of lights on
the string? e.g., low frequencies would turn on the blue lights, lower-mid
frequencies the blue ones, upper-mid the red, and high frequencies the
yellow ones. I think it would be a pretty neat effect to have a set of
lights on the tree (or wherever) that "blinked" to the "ambient" Christmas
music, or Christmas carols, or whatever!
I don't have R-E going back to when Don Lancaster had his "organ lights"
(or whatever he called it back then) which was similar to what I want
to do - except I think that OLD article is probably a little out of date
for the times anyway... 8-)
Any suggestions on this? Somebody wanna whip up a circuit for me? (I'm
still working on my BS... ;-)
aTdHvAaNnKcSe,
E.J.G.
--
Eddy J. Gurney, N8FPW THE ECCENTRICITY GROUP
eddy@jafus.mi.org -- gurney@frith.egr.msu.edu -- 17158EJG@MSU.BITNET
(Preferred) (But this is OK too) (Only if you have to :-)levene@aplcomm.jhuapl.edu (Robert A. Levene) (11/03/90)
In article <1990Nov2.142454.10784@msuinfo.cl.msu.edu> gurney@kira.msu.edu (Eddy J. Gurney) writes: >.. How hard would it be to use a similar audio filter and instead of >lighting a bunch of LEDs, turn on one of the four groups of lights on >the string? ... A similar project involving 4-color "rope" party lights was done about two years ago as a Junior project by Robert Lefkowitz at the Univ. of Pennsylvania, Phila., PA. I don't have his whereabouts now, but if you contact Penn's Moore School of E.E., they should be able to locate him. If they can't find him, send me mail and I'll try to reach him. -- Robert A. Levene Internet: levene@aplcomm.jhuapl.edu Bitnet: RXL1@APLVM Disclaimer: I speak neither for my race, my culture, my country, my religion, my political party, nor my employer, but for me alone.
bender@oobleck.Eng.Sun.COM (Michael Bender) (11/03/90)
In article <1990Nov2.142454.10784@msuinfo.cl.msu.edu> gurney@kira.msu.edu (Eddy J. Gurney) writes: >I just got done reading the latest issue of Radio-Electronics. Or at >least part of it. :-) There's an article in the December issue on building >a "Christmas card" that has 50 LEDs that blink in response to an AGC'd >microphone audio input. The article explains that they're really just >"bar drivers", driven in either dor or bad mode, depending on the singal >level. > >I think it would be a pretty neat effect to have a set of >lights on the tree (or wherever) that "blinked" to the "ambient" Christmas >music, or Christmas carols, or whatever! Back in 1978 I connected my home-built "sound-light" (a term my friends and I used to impress our other high-school friends!), which was a 3-channel color organ, to our family's Christmas tree and played some Christmas music through it (and the stereo). I thought it was really neat. When my parents got home from shopping, they told me to unplug it and wire the tree back to the way it was (no blinking lights or anything). Oh, well, I guess they just weren't ready for the onslaught of technology in the home at that time. mike -- Won't look like rain, Won't look like snow, | DOD #000007 Won't look like fog, That's all we know! | AMA #511250 We just can't tell you anymore, We've never made oobleck before! | MSC #298726
kimf@nntp-server.caltech.edu (Kim Dorian Flowers) (11/03/90)
bender@oobleck.Eng.Sun.COM (Michael Bender) writes: >Back in 1978 I connected my home-built "sound-light" (a term my friends and >I used to impress our other high-school friends!), which was a 3-channel >color organ, to our family's Christmas tree and played some Christmas music >through it (and the stereo). I thought it was really neat. When my parents >got home from shopping, they told me to unplug it and wire the tree back to >the way it was (no blinking lights or anything). Oh, well, I guess they just >weren't ready for the onslaught of technology in the home at that time. What's the basic concept behind your "typical" color organ? The general intensity of sound over several different frequency ranges? Kim Flowers kimf@tybalt.caltech.edu
bender@oobleck.Eng.Sun.COM (Michael Bender) (11/05/90)
In article <1990Nov3.024908.18792@nntp-server.caltech.edu> kimf@nntp-server.caltech.edu (Kim Dorian Flowers) writes: >bender@oobleck.Eng.Sun.COM (Michael Bender) writes: > >>Back in 1978 I connected my home-built "sound-light" (a term my friends and >>I used to impress our other high-school friends!), which was a 3-channel >>color organ, to our family's Christmas tree and played some Christmas music >>through it (and the stereo). I thought it was really neat. When my parents >>got home from shopping, they told me to unplug it and wire the tree back to >>the way it was (no blinking lights or anything). Oh, well, I guess they just >>weren't ready for the onslaught of technology in the home at that time. > >What's the basic concept behind your "typical" color organ? The general >intensity of sound over several different frequency ranges? In my setup (and that seemes to be true for most of the other designs that I've seen), I used 3 channels - the incoming audio signal would be set to a low pass filter to one channel, a band pass filter to another channel and a high pass filter to the remaining channel. The results of this was that one channel of lights would respond to the low frequencies in the audio program, one to the midrange frequencies and one channel to the high frequencies. I was building these devices during the late 70's when disco was king and everyone in town wanted to added lighting effects to their parties and dances and things. mike p.s. as I found out the hard way, it's very important to use an isloating transformer between the audio inout and the rest of the circuit if you're not using opto-isolated triacs or scr's... -- Won't look like rain, Won't look like snow, | DOD #000007 Won't look like fog, That's all we know! | AMA #511250 We just can't tell you anymore, We've never made oobleck before! | MSC #298726