Ife and Efe Matrix of Godrej Interio
Real world Applications of Electronics
This chapter introduces some of the real world applications of Electronics; 1. Audio Systems 2. Radio Transmission & Reception 3. Control Systems 1. AUDIO SYSTEMS: Any system operating at audio frequencies (20 to 20,000 Hz) is called an Audio System, e.g. an intercom, music systems etc. Following diagram (fig.1.1) shows the main features of such an audio system;
FIGURE 1.1: Main blocks of an audio system 1.1 Radio tuner: It receives radio signals and converts them into electrical signals.
FIGURE 1.2 1.2 CD player: It converts music and sound recorded digitally on a compact disc (CD) into analogue electrical signals. A CD consists of two plastic layers with a silvered coating sandwiched between them (above fig. 1.2). As shown in fig. 1.2, a series of dimples having spaces between them is used to record the music and sound data. Digital logic ‘1’ represented by a dimple and a space represents logic ‘0’. A beam of light from a low-power laser is focused on the spinning disc from below. The beam is reflected back in case there is no dimple, and gets detected by a photodiode. Where there is a dimple, the beam is scattered sideways and is not detected. This provides a stream of bits, either ‘0’ or ‘1’. Complex logic circuits process these 1s and 0s, eventually producing two analogue signals for the left and right stereo channels. 1.3 Tape deck: Relatively newer audio systems do not have a tape deck, but there are still plenty of older systems which use magnetic tapes for recording music & sound data. The plastic tape is coated with a layer containing a magnetic substance such as chromium dioxide. This becomes organized into microscopic regions known as domains. Each domain is equivalent to a very small magnet. In an unrecorded tape, the domains are arranged irregularly, so there is no overall magnetization.
FIGURE 1.3
To record sound on a tape deck the tape passes through a gap in a magnetic recording head. A signal from an
This chapter introduces some of the real world applications of Electronics; 1. Audio Systems 2. Radio Transmission & Reception 3. Control Systems 1. AUDIO SYSTEMS: Any system operating at audio frequencies (20 to 20,000 Hz) is called an Audio System, e.g. an intercom, music systems etc. Following diagram (fig.1.1) shows the main features of such an audio system;
FIGURE 1.1: Main blocks of an audio system 1.1 Radio tuner: It receives radio signals and converts them into electrical signals.
FIGURE 1.2 1.2 CD player: It converts music and sound recorded digitally on a compact disc (CD) into analogue electrical signals. A CD consists of two plastic layers with a silvered coating sandwiched between them (above fig. 1.2). As shown in fig. 1.2, a series of dimples having spaces between them is used to record the music and sound data. Digital logic ‘1’ represented by a dimple and a space represents logic ‘0’. A beam of light from a low-power laser is focused on the spinning disc from below. The beam is reflected back in case there is no dimple, and gets detected by a photodiode. Where there is a dimple, the beam is scattered sideways and is not detected. This provides a stream of bits, either ‘0’ or ‘1’. Complex logic circuits process these 1s and 0s, eventually producing two analogue signals for the left and right stereo channels. 1.3 Tape deck: Relatively newer audio systems do not have a tape deck, but there are still plenty of older systems which use magnetic tapes for recording music & sound data. The plastic tape is coated with a layer containing a magnetic substance such as chromium dioxide. This becomes organized into microscopic regions known as domains. Each domain is equivalent to a very small magnet. In an unrecorded tape, the domains are arranged irregularly, so there is no overall magnetization.
FIGURE 1.3
To record sound on a tape deck the tape passes through a gap in a magnetic recording head. A signal from an