What is reactance modulator in FM?
What is reactance modulator in FM?
The reactance modulator takes its name from the fact that the impedance of the circuit acts as a reactance (capacitive or inductive) that is connected in parallel with the resonant circuit of the Oscillator.
How is FM signal generated by reactance modulator circuit?
Reactance Modulator The frequency of this oscillator is changed by changing the reactive components involved in the tuned circuit. If L or C of a tuned circuit of an oscillator is changed in accordance with the amplitude of modulating signal then FM can be obtained across the tuned circuit as shown in figure 1 below.
What is the Armstrong method?
From Wikipedia, the free encyclopedia. In 1933, Edwin H. Armstrong patented a method for generating frequency modulation of radio signals. The Armstrong method generates a double sideband suppressed carrier signal, phase shifts this signal, and then reinserts the carrier to produce a frequency modulated signal.
What is inductive reactance tube modulator?
An electron-tube circuit, used to produce phase or frequency modulation, in which the reactance is varied in accordance with the instantaneous amplitude of the modulating voltage.
Which FM detector has very good linearity?
However as the inductor is only a coil and not a transformer the cost impact can be accommodated for many radio receiver designs. In terms of its performance, the quadrature detector and its relation the coincidence detector offer a high level of performance with excellent linearity.
Why is a balance modulator used?
The balanced modulators are used to suppress the unwanted carrier in an AM wave. The carrier and modulating signals are applied to the inputs of the balanced modulator and we get the DSB signal with suppressed carrier at the output of the balanced modulator.
Why Armstrong is indirect method?
Armstrong method of FM generation is the indirect method because the modulating signal directly varies the phase of the carrier, which indirectly changes the frequency.
What does a varactor do?
Varactor or varicap diodes are used mainly in radio frequency or RF circuits to provide voltage controlled variable capacitance. These electronic componenta can be used in a whole variety of ways where a capacitance level needs to be controlled by a voltage.
What is re-reactance modulator?
Reactance Modulator In direct FM generation, the instantaneous frequency of the carrier is changed directly in proportion with the message signal. For this, a device called voltage controlled oscillator (VCO) is used. A VCO can be implemented by using a sinusoidal oscillator with a tuned circuit having a high value of Q.
What is a reactance modulator and varicap?
The reactance modulator takes its name from the fact that the impedance of the circuit acts as a reactance (capacitive or inductive) that is connected in parallel with the resonant circuit of the Oscillator. The varicap can only appear as a capacitance that becomes part of the frequency determining branch of the oscillator circuit.
What is a saturable reactor modulator?
The FM circuit using such inductors is called saturable reactor modulator. Frequency modulation can also be achieved from voltage controlled devices such as P IN diode, Klystron oscillators and multivibrators. In direct FM generation, the instantaneous frequency of the carrier is changed directly in proportion with the message signal.
How to solve block diagram reduction problems?
Let us now see an example to have a better understanding of the same. First, see the procedural steps to be followed for solving block diagram reduction problems: The directly connected blocks in series must be reduced to a single block. Further, reduce the parallely connected block into a single block.
