Definition: Cathode ray tube, CRT is the heart of CRO which generates images when electron beam from the back of the tube strikes the fluorescent screen with sufficient energy. CRT technique was basically employed in conventional TV and computer screens. Constructional details of Cathode Ray Tube CRT consist of the following parts: Electron gun Deflection plate assembly Glass envelope Fluorescent screen Base, for connections The diagram given below shows the internal … [Read more...] about Cathode Ray Tube (CRT)
Linear variable differential transformer (LVDT)
Definition: LVDT, Linear variable differential transformer is an inductive transducer which converts linear motion or displacement into electrical signals. LVDT works on the principle of mutual induction. Here, the word differential is used as the output value we get is the difference value of voltages produced at the two secondary windings. Displacement provided is directly proportional to the output voltage generated. Constructional Details of LVDT The transformer has a single primary … [Read more...] about Linear variable differential transformer (LVDT)
Frequency Division Multiplexing (FDM)
Definition: Frequency division multiplexing is a multiplexing technique in which multiple separate information signals can be transmitted over a single communication channel by occupying different frequency slots within common channel bandwidth. FDM technique is basically used for muxing of analog signals. Look at the figure given below to understand how multiple signals can be transmitted over a common channel. In Frequency division multiplexing simultaneous transmission of the … [Read more...] about Frequency Division Multiplexing (FDM)
Power Amplifier
Definition: Power amplifiers are basically used to enhance the power level of the input signal. Power amplifier is also called large signal amplifiers, as in order to get large power at the output, input signal voltage required must also be large. The transistors that are employed in power amplifiers are termed as power transistors. Key terms of Power Amplifier Collector Efficiency: Efficiency is basically measured by the ability to convert dc power into ac power at the output. It is … [Read more...] about Power Amplifier
Superheterodyne Receiver
Definition: Superheterodyne receiver works on the principle of heterodyning which simply means mixing. It is a type of receiver which mixes the received signal frequency with the frequency of the signal generated by a local oscillator. The output of mixer provides a lower fixed frequency also known as intermediate frequency. These receivers are called Superheterodyne receivers as the frequency of the signal generated by the local oscillator is more than the frequency of the received … [Read more...] about Superheterodyne Receiver
Modulation
Definition: Modulation, the process in which the carrier signal is varied according to the information bearing signal also called the modulating signal. During modulation, some characteristics it can be amplitude, frequency, or phase is varied in accordance with the original information-bearing signal that has to be transmitted. The receiver at the destination end won’t be able to understand that particular modulated signal so it uses demodulator section and demodulates that signal so as … [Read more...] about Modulation
Communication System
Definition: Communication system basically helps in transmitting the data from an end to the other through a proper medium or channel. Based on the direction of transmission and reception the system is classified into two domains. The classification is such that: Unidirectional system or simplex system Bidirectional system or duplex system Half duplex system Full duplex system Simplex System This system allows one-way communication as it is only capable of … [Read more...] about Communication System
LCR Meter
Definition: LCR meters can be understood as a multimeter, this is because it can measure resistance, inductance, capacitance as per the requirement. Thus, it is termed as LCR meter. L in its name signifies inductance, C stands for capacitance and R denotes resistance. The significant component of LCR meter is the Wheatstone bridge and RC ratio arm circuits. The component whose value is to be measured is connected in one of the arms of the bridge. There are different provisions for the … [Read more...] about LCR Meter
DC Voltmeter
Definition: The DC voltmeter is a device which measures the DC voltage applied to it, by moving the pointer against the perfectly calibrated scale. The calibrated scale is provided by PMMC meter. Also, you must note here that the voltage which is to be measured is passed through the attenuator and then through the DC gain amplifier. In order to understand the working of DC voltmeter, we may refer to the block diagram below. We can conclude from the diagram below that when the DC voltage is … [Read more...] about DC Voltmeter
Electronic Multimeter
Definition: The Electronic Multimeter is a device which is used for the measurement of various electrical and electronic quantities such as current, voltage, resistance etc. The multimeter name is given to it to define its ability to measure multiple quantities. It is provided with inbuilt power supply necessary for the functioning of the device. Any component such as a resistor, battery can be connected to its outer probes for the measurement of the electronic quantity. In order to … [Read more...] about Electronic Multimeter