Today, you will learn to make a variable resistor. Now before we start let me tell you about variable resistors. Variable Resistors are resistors that have a physical input for a specific amount of resistance. These can be used in LED dimming, Volume control, and many other projects and now you know the basics of Variable Resistors, so let’s get started!
Firstly, you will need
1. A sheet of paper
2. A 6B Pencil (You will need a normal pencil and a penpencil will not work)
3. Alligator Clips
4. A 9-volt battery
Draw a thick rectangle on a sheet of paper. This will be used as the resistor for the LED
Here in this circuit, I connected the positive of a nine-volt battery to the positive leg of a small green LED and then I also connected the negative of the nine-volt battery to one side of the graphite rectangle, NEVER connect a nine-volt battery straight to a LED as the LED will burn but in this circuit, the graphite will act as the resistor. After this your DIY Variable Resistor is ready! but there’s a problem, How will we use it?
Well, to use it we just need to touch the black alligator clip to one edge of the rectangle then we’ll just connect the negative leg of the LED to the rectangle. After this, the LED will glow and to adjust the brightness you have to move the LED closer to the black alligator clip but remember not to bring it too close because the 9 volts from the battery is too much for the LED to handle, to prevent burning the LED you can add a 350-ohm resistor to the positive or negative leg of the LED.
Bye!
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