Parametric Amplifier: The parametric amplifier uses a device whose reactance is varied in such a manner that amplification results. It is low-noise because no resistance need be involved in the…
Varactor Diode Operation and Characteristics: Varactor Diode Operation and Characteristics were first used in the early 1950s as simple voltage-variable capacitance and later for frequency modulation of oscillators. They thus…
High Frequency Limitations: As stated, transistors suffer from High Frequency Limitations. These are of a twofold nature. On the one hand, there are the same difficulties as those encountered with…
Triode Equivalent Circuit: Triode Equivalent Circuit - As frequency is raised, vacuum tubes suffer from two general kinds of problems. The first is concerned with interelectrode capacitances and inductances, and…
Resonators and Waveguides Articles: Rectangular Waveguides: As we know already that the term skin effect indicated that the majority of the current flow (at very high frequencies) will occur mostly…
Radio Receivers Articles: Tuned Radio Frequency Receiver: The Tuned Radio Frequency Receiver is a simple “logical” receiver. A person with just a little knowledge of communications would probably expect all…
Delayed Automatic Gain Control: Delayed Automatic Gain Control: Simple AGC is clearly an improvement on no AGC at all, in that the gain of the receiver is reduced for strong…
Working Principle of Automatic Gain Control: Working Principle of Automatic Gain Control is a system by means of which the overall gain of a radio receiver is varied automatically with…