In this Instructable you will be making a sound light system from recycled components. Unfortunately, you might find yourself purchasing additional components to complete this Instructable. This is not very much the case with the other circuits that we publish on our websites.

I got the idea for this circuit from the following three Instructables:

https://www.instructables.com/id/Simple-Sound-Lights

https://www.instructables.com/id/Crazy-Sound-Light

https://www.instructables.com/id/Sound-Light-Robot

The first two are simple and do not work well. The last one works well but is expensive. Thus I believe came up with a compromise but I could be wrong.

Someone else in Australia designed the following circuit that needs testing and improvements:

https://dr-mark-glickman-circuits.webnode.com

If you have time you can leave a comment if you managed to build this circuit.

This circuit can be used as light dimmer. However, a better light dimmer that an electronics novice can make is shown here:

https://www.instructables.com/id/LM350-Power-Supply

Supplies

Components: power transistor, bright LED - 2, 1 kohm resistor - 5, 100-ohm power resistor - 1, 10-ohm power resistor -1, heat sink, heat transfer paste, 10 uF bipolar capacitor - 1, 10 uF, 22 uF, 47 uF or 100 uF low power electrolytic capacitor - 1, matrix board, 1 Megohm variable resistors, insulated wires, 9 V power source, music source.

Tools: wire stripper, scissors, pliers.

Optional tools: USB Oscilloscope, soldering iron.

Optional components: solder, metal wire.

Step 1: Design and Simulations

The maximum current is:

Iledmax = Vs / (Rled + Rf) = 9 V / 1100 ohms = 8.18 mA

The best way to choose a capacitor value is to purchase a few values between 10 uF and 100 uF and see which one you like. You can also include a rotary switch. However, this is not what recycled circuits is all about.

The capacitors that I used could be too low in power, voltage, and current ratings because they are very small. However, I do not think that you need high power capacitors either.

Step 2: Attach the Power Transistor

Attach with bolts, screws or metal wire.

Step 3: Build the Circuit

The circuit is easy to build. You need a bipolar capacitor for music input only. You do not need a high power 1 kohm resistor. I just had it in stock.

You can read the blue resistor colour codes from left to right as follows:

1. Brown - 1

2. Black - 0

3. Black - 0

4. Brown - 2

5. Brown - Tolerance (resistor precision)

This it is 100 and additional 2 zero digits from line "4", making it 1,000 ohms or 1 kohm. The resistor precision is how close is the actual resistance to 1,000 ohms. If resistor tolerance is 10 %, then the resistor value could be anywhere from 900 ohms to 1,100 ohms.

Step 4: Testing With Music

The circuit does not work well with light bulbs. It needs more AC gain and one transistor cannot provide it.

Also, the bright LED is not working well for talking speech. Only for techno.

Step 5: Testing As Light Dimmer

This video shows how the circuit can be used as a light dimmer.

However, a better light dimmer that an electronics novice can make is shown here:

https://www.instructables.com/id/LM350-Power-Suppl...

Thanks for reading.