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How can I make a series of LEDs, powered by a wall plug, flash to an audio source? Answered

The following Instructable is really helpful, but I don't understand the circuit diagram and the picture that shows how everything is connected isn't very good. I have to build a house project for physics and I wanted to incorporate this thing into it. We are allowed to use plans from this website, I just need some help. Could anyone explain the diagram to me or -even better- take a picture of what the actual setup looks like when everything is soldered together (I just need to know what connects to what)...

Also, I need to power it off of a 9v wall transformer...




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11 years ago

Yeah, it looks a bit ugly in the make. But it is shown well enough in the diagram.
Look at the circuit diagram which I think I've linked here
The 9V supply connects at the top & bottom + / -. The square things with the * in them are resistors, what you use depends upon your LEDs - try this to help you:

The audio outputs seem to be connected directly to over-size transistors, this doesn't look right whether it works or not. You should search about a bit (e.g. here) for some better usage of transistors, they're just being used as switches, triggered by the audio signals.