Tunnel Diode Applications: In all its Tunnel Diode Applications, the tunnel diode should be loosely coupled to its tuned circuit. With lumped components, this is done by means of a…
Negative Resistance Amplifier: The classical application of the tunnel diode was in microwave oscillators, especially after it was realized that the secret of stable oscillations lay in loosely coupling the…
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…
Frequency Multiplier Circuit: A typical Frequency Multiplier Circuit chain is shown in Figure 12-11, The first stage is a transistor crystal oscillator, operating in the VHF region, and this is…
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…
Types of Travelling Wave Tubes: The TWT is the most versatile and most frequently used microwave tube. Four Types of Travelling Wave Tubes, each with particular applications and performance requirements.…
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…