TV remote controls mainly rely on integrated circuits (also called chips) to send instructions. The chip uses an 18-pin dual in-line package (dual in-line package abbreviated as DIP). On the right side of the chip, you can see a diode, a transistor (black, with three pins), a resonator (yellow), two resistors (green) and a capacitor (dark blue). There is a resistor (green) and a capacitor (a small brown disc) beside the battery contacts. In this circuit, the chip can detect when a button is pressed. Then, it encodes the key information in a form similar to Morse code, and the encoding of each key is different. The chip will send these signals to the transistor for amplifying processing, so that the signal is enhanced.