Where can I find this....

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andyman2u
 
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Joined: Thu Feb 05, 2009 4:15 pm

Where can I find this....

Post by andyman2u »

I used to be a Mutli-Image (multiple slide projectors) programmer 'back in the day'. I want to use the same technique to 'program a show'. In other words, I want to 'program' something to music. I'll put music on one channel and on the other have 'cues' which will feed into some kind of interface that will translate that info into relay closures (controlling something else).
All of my old A/V programing equipment seems to have died while sitting on the shelf all these years. Does anyone know of some existing technology that will do what I need? Is this something that a Arduino project could do?
How's that for Rambling? :wink:

andyman2u
 
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Joined: Thu Feb 05, 2009 4:15 pm

Re: Where can I find this....

Post by andyman2u »

I've thought about this a little more... Maybe the simplest way to go would be to use 'tones'. Using Audacity (a great little free audio editor) I could generate various tones (1000HZ, 900HZ etc) on my cue track. Now I need to find a circuit that will accept an audio line in and give me a separate 'momentary On' for each tone that it 'hears'. Any thoughts, or am I still rambling? :?

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Franklin97355
 
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Re: Where can I find this....

Post by Franklin97355 »

No, I think what you propose is on the right track. you could use a diode and cap to filter the signal and feed it into your controller.

andyman2u
 
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Joined: Thu Feb 05, 2009 4:15 pm

Re: Where can I find this....

Post by andyman2u »

Forgive my ignorance, but is there someplace I could find a schematic for such a circuit?

Andy

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karlgg
 
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Joined: Sat Dec 27, 2008 2:41 pm

Re: Where can I find this....

Post by karlgg »

I don't have any circuit links on hand, but read up on FSK (or specifically, AFSK). It's basically how modems, and even the old cassette interfaces, worked. ("EEEE-ooooo-EEEE? That's a FIVE!") There are chips you can buy to do it all for you, I think even Radio Shack used to carry one.

http://en.wikipedia.org/wiki/Frequency-shift_keying

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westfw
 
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Re: Where can I find this....

Post by westfw »

If you use touch-tones (two tones played together), you can get 16 different combinations with very little bandwidth requirements, AND you can buy an off-the-shelf touch-tone decoder IC that is easy to interface to assorted things (although they seem somewhat rare.)

http://www.rainbowkits.com/kits/TT-16p.html (kit - 16 signals, one relay)
http://www.bgmicro.com/index.asp?PageAc ... odID=10622 (bare chip. Datasheet at same site)
http://uk.farnell.com/1420879/semicondu ... 0d-18soplf (another chip)

I think I've read that people have managed to used a microcontroller to decode DTMF directly, with as little as a one-bit A-D converter (ie comparator and digital pin.) Ahh yeah: http://www.dattalo.com/technical/theory/dtmf.html and http://mondo-technology.com/qdft.html ! That's all black magic to me, though (It'd be a good project for someone to port to Arduino or similar, though!)

andyman2u
 
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Re: Where can I find this....

Post by andyman2u »

Thanks, guys. I appreciate the input.

Andy

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