Three Ways of Connecting Potentiometer in Circuits with Circuit Diagram

          Connecting potentiometers in circuit is always a confusing task to many electronic beginners. Potentiometers are unavoidable in circuits such as audio controls where adjustment of resistance is needed. Potentiometers can be connected in three ways in a circuit. One is to get maximum resistance and the others are to get a variable resistance from zero to maximum.

          Circuit to get variable resistance from zero to maximum value is given below. In this circuit, connections are taken across the middle terminal and one end terminal of the potentiometer. When the sliding contact is rotated in one direction, resistance will increase from zero to maximum.

          Another circuit to get variable resistance from zero to maximum value is given below. In this circuit, connections are taken across the middle terminal and end terminal opposite to the end terminal connected in the above circuit. When the sliding contact is rotated in the opposite direction, resistance will increase from zero to maximum. This change in resistance will change the brightness of LED.

          Next is the circuit to get maximum resistance across the potentiometer. If connections are taken across the end terminals of potentiometer, circuit will have maximum resistance.

How to Flip (Mirror Image) an Image using GIMP in Ubuntu ?

          Flipping or creating mirror images are important under certain situations. Many software are there which will help us to flip images horizontally or vertically. GIMP in Linux also provides a user friendly approach for flipping images. Follow the simple instructions given below to flip your images vertically or horizontally using GIMP.

1. Open your image in GIMP.
2. Select the layer to be flipped using Page Down or Page Up keys.
3. Now go to Layer => Transform => Flip Horizontally to flip your image horizontally. Similarly, go to Layer => Transform => Flip Vertically to flip your image Vertically as shown in the following images.

Original Image

Vertically Flipped Image

Horizontally Flipped Image

How to Turn On an LED Using Battery?

          I have found many electronics beginners connecting LED directly to battery. They are not aware about the aftereffects of connecting LED to voltage source directly. LED get damaged if LED is directly connected to voltage source because of the high current that flows through the LED. Since the resistance of LED is very low, a large current will flow through the LED which will permanently damage the LED. To avoid this problem, we are using a current limiting resistor in series to the LED. Value of the current limiting depends on the type of LED. Normally resistors of 1K is connected as current limiting resistors. Circuit is done as shown in the following diagram.