This simple tool can be used to test many electronic components if they are working well. It is Easy to build using cheap materials. Some of them can be found in your home.
Step 1: Materials
Some useful tools and materials you need are:
Jumper Wires #22
Battery Holder AA(This can be salvaged in old toys):
2 1.5 V batteries
1 3V cell battery
Step 2: LED tester
Use cutter to cut the styrofoam to a small piece. Then use the cutter to cut a rectangular hole and insert the 3 V battery. Puncture 2 Holes on the top. This is where you will test the LED
Step 3: Resistor Tester
Create a circuit that has power source, LED and leave the area for the resistor. Now use the cutter to cut a portion of the styro. Insert two conductive materials parallel to each other. The circuit is open and it should be close when an LED is placed.
Step 4: Potentiometer Tester
Create a circuit similar to the resistor tester except replace the LED with a buzzer. Then leave two jumper wires with hooks. This is where you will hook the potentiometer.
Step 5: Assembling the Circuit
Connect the Resistor Tester and the Potentiometer tester with a push button switch with 3 terminals. The middle terminal has the only different charge. The two testers should be parallel with each other and used the switch to switch between the two.
Step 6: Finishing
Attach them to and old box with a gluestick. Make sure there is no short circuit. Tape the stray wires in the box to avoid short circuits. Then it is ready to test many electronic components!