Author: John Mulindi
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Types of AM Radio Receivers
A radio receiver is a device which reproduces the modulated or radio waves into sound waves. The radio receivers used in reproducing amplitude modulated signals are called AM radio receivers. So as to reproduce the AM wave into sound waves, every radio receiver must perform the following functions: Related: General Principles of Radio Broadcasting, Transmission…
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Proportional-Integral-Derivative (PID) Control Systems
Proportional-Integral-Derivative For processes that are able to operate with continuous cycling, the relatively inexpensive two position controller is sufficient. For processes that cannot tolerate continuous cycling, a proportional controller is used. For processes that tolerate neither cycling nor offset error, a proportional plus integral/reset controller can be used. For processes that require improved stability and…
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Proportional plus Derivative (PD) Control System
Proportional plus derivative (rate) control is a control mode in which a derivative section is added to the proportional controller. This derivative section responds to the rate of change of the error signal, not the amplitude as with the integral control; this derivative action responds to the rate of change the instant it starts. This…
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Why you should replace your old DCS systems with modern ones
To keep up with evolving technology manufacturers need to upgrade their legacy Distributed Control Systems (DCS). This might be a challenging task to undertake and at a cost to the company, but in the long run the benefits outweigh the costs of doing the upgrade. The legacy DCS systems faces increased components failure that leads…
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Demodulation in Telecommunication Systems
Demodulation is the process of recovering the audio signal from the modulated wave. Demodulation is also known as detection in communication systems. Why Demodulation is needed in Telecommunication Systems Amplitude modulated wave consists of carrier and sideband frequencies. The audio signal is contained in the sideband frequencies which are radio frequencies. If the modulated wave…
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Proportional Plus Integral (PI) Control System
This type of control is combination of two control modes, proportional and integral (reset). The Combining of the two modes results in gaining the advantages and compensating for the disadvantages of the two individual control modes. The main advantage of the proportional control is that an immediate proportional output is produced as soon as an…
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Modulation in Communication Systems
Introduction Modulation is the process of changing some characteristics (e.g. Amplitude, Frequency, or Phase) of a carrier wave in accordance with the intensity of the message signal. Modulation means to ‘’change’’. In Modulation, some characteristics of the carrier wave is changed in accordance with the intensity i.e. amplitude of the message signal. The resultant wave…
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RF Scalar and Vector Network Analyzers
The RF network analyzer is an active test instrument which generates a signal that is applied to the device under test, and then it measures the response. Functions of a RF Network Analyzer Signal Separation The signal separation element is often called the test set. It provides two functions: Receiver and Signal Detection When signal…
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DC Networks Theorems
The laws that determine the currents and voltage drops in DC networks: In addition to the above laws, we have several circuit theorems used to solve problems in electrical circuits and they include: Kirchhoff’s Laws Kirchhoff’s laws states that : Current law – At any junction in an electric circuit, the total current flowing towards…
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Key Facts about Resistors, Resistor Colour Codes and Resistor Tolerance
Resistors perform two basic functions in electronics: These two Resistor features of current limiting and voltage setting are implemented in various ways in electronics as listed below: The figure below shows how a resistor is used as a current limiter: The figure below demonstrates how a resistor is used to create a voltage divider capable…