In this lesson we learned about LEDs, different types of transistors, and microphone resistors.

LEDs are made from semiconductors which have more resistance than metal conductors but have less insulators. Transistors are current amplifiers that use a small amount of current to control a large amount of current. There are two types of transistors in the kit: NPN-type and PNP-type. The NPN-type emits energy from the collector to the base and then to the emitter. On the other hand the PNP-type emits energy through the emitter, then base, then collector. We also learned about the microphone part. The microphone part is a resistor that changes when exposed to different sound waves.

For project 125 we built a mechanism that uses a adjustable resistor to send a certain amount of electricity to the light bulb. For the other project we built a red light that turned on from the switch.

~PTMS Student