Hi guys!
A few days ago my housemates and I went on a night out, much drunkenness etc occurred and on our way back we spotted the severed "head" of a traffic light in a skip. In our drunken stupor we thought it'd be a great addition to the living room, so we dragged it home.
Next day we cleaned it and rewired all the lamps to a mains plug, and surprisingly it worked! Only problem is, it shines far too brightly and all 3 lights shine constantly. We had a brainwave and came up with the idea to modulate the intensity of the lights with a musical input. We'd like to make it so that the green light varies with bass frequencies, the yellow light with mid frequencies and the red light with treble frequencies.
I had a root around on the internet and found that the easiest way to do this would be to:
1) solder some wires onto the connector wire between the ipod and the hifi to get the musical output
2) split this into 3, one for each light, then bandpass filter the signal to get it to the desired frequency range
3) rectify this signal to get a DC output voltage depending on the signal strength of the music in that frequency range.
4) Use this voltage to trigger a triac used as part of a dimmer switch circuit
This makes a lot of sense as a general idea but I'm having a bit of trouble fully designing the circuit as my knowledge of electronics is pretty basic!
I had a bash at designing something, see the attachment (excuse the crappy mspaint)
As far as I can tell, the voltages across the 3 diode bridges should be fully rectified copies of the music, filtered to the frequencies I select via the RC value of the filters. The trouble I'm having is I'm unsure how to connect this to the triac that's connected to the mains. The areas I'm talking about are circled in red on the diagram. There are two outputs from the rectifier and the triac gate is only one input, and I'm not too sure what I need to do. Like I said, my electronics knowledge is pretty basic and I'm probably missing a load of stuff on this so if anyone could have a look over this and point out where I'm going wrong and what I need to do it'd be much appreciated. Thanks!
A few days ago my housemates and I went on a night out, much drunkenness etc occurred and on our way back we spotted the severed "head" of a traffic light in a skip. In our drunken stupor we thought it'd be a great addition to the living room, so we dragged it home.
Next day we cleaned it and rewired all the lamps to a mains plug, and surprisingly it worked! Only problem is, it shines far too brightly and all 3 lights shine constantly. We had a brainwave and came up with the idea to modulate the intensity of the lights with a musical input. We'd like to make it so that the green light varies with bass frequencies, the yellow light with mid frequencies and the red light with treble frequencies.
I had a root around on the internet and found that the easiest way to do this would be to:
1) solder some wires onto the connector wire between the ipod and the hifi to get the musical output
2) split this into 3, one for each light, then bandpass filter the signal to get it to the desired frequency range
3) rectify this signal to get a DC output voltage depending on the signal strength of the music in that frequency range.
4) Use this voltage to trigger a triac used as part of a dimmer switch circuit
This makes a lot of sense as a general idea but I'm having a bit of trouble fully designing the circuit as my knowledge of electronics is pretty basic!
I had a bash at designing something, see the attachment (excuse the crappy mspaint)
As far as I can tell, the voltages across the 3 diode bridges should be fully rectified copies of the music, filtered to the frequencies I select via the RC value of the filters. The trouble I'm having is I'm unsure how to connect this to the triac that's connected to the mains. The areas I'm talking about are circled in red on the diagram. There are two outputs from the rectifier and the triac gate is only one input, and I'm not too sure what I need to do. Like I said, my electronics knowledge is pretty basic and I'm probably missing a load of stuff on this so if anyone could have a look over this and point out where I'm going wrong and what I need to do it'd be much appreciated. Thanks!
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