Presentation on theme: "Communication systems Radios. Input Raw materials in a radio are an antenna, printed circuit board, resistors, capacitors, coils and transformers, transistors,"— Presentation transcript:
Input Raw materials in a radio are an antenna, printed circuit board, resistors, capacitors, coils and transformers, transistors, integrated circuits, and a speaker. All of these parts are housed in a plastic case. Design-Radios consist of many specialized electronic circuits designed to perform specific tasks—radio frequency amplifier, mixer, variable frequency oscillator, intermediate frequency amplifier, detector, and audio amplifier. The simplest AM/FM radio will have all of these circuits mounted on a single circuit board. Most of these circuits can be contained in a single integrated circuit.
Process There is no single process for manufacturing a radio. The manufacturing process depends upon the design and complexity of the radio.
Output Today's environmental awareness dictates that all waste be disposed of properly. Most byproducts from the construction of a radio can be reclaimed. The etching solutions used in the printed circuit board manufacture are sent to chemical reclamation centers. Scraps from the leads of electronic components are sent to metal waste recovery centers where they are melted to create new products.
Feedback Radios are being combined with computers to connect the computer to the Internet via satellites. Eventually radios will convert from analog to digital broadcasting. Analog signals are subject to fade and interference, digital signals are not. They can produce high quality sound like that found on a CD.
For radios to work, sound and radio waves are needed. A sound wave is produced with a frequency of 5 Hz - 20 kHz. The sound wave is equivalent to a pressure wave traveling through the air. A microphone converts the sound wave into an electrical signal. The electrical wave traveling through the microphone wire is analogous to the original sound wave. The electrical wave is used to encode or modulate a high-frequency "carrier" radio wave. The carrier wave itself does not include any of the sound information until it has been modulated.
How sound waves work (continued) The carrier wave can either be amplitude modulated (AM, top) by the electrical signal, or frequency modulated (FM, bottom). The signal is transmitted by a radio broadcast tower.