What is a reactance modulator?

What is a reactance modulator?

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.

Which device is used in reactance modulator?

Reactance Modulator 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. The frequency of this oscillator is changed by changing the reactive components involved in the tuned circuit.

What is reactance modulator in FM transmitter?

The reactance modulator gets the modulating signal as input. It operates on the tank circuit of an LC master oscillator. The output of this oscillator is FM signal. It is passed through a buffer and amplitude limiter before it is applied to the Class C power amplifier.

How does a transistor work as a modulator?

The modulating signal is applied in the emitter resistance circuit. The amplifier circuit amplifies the carrier by a factor “A” so that the output is Aec. Since the modulating signal is part of the biasing circuit it produces low-frequency variations in the circuit. This in turn causes variations in “A”.

What is AM transmitter and receiver?

The amplitude-modulated (AM) transmitter produces an electromagnetic carrier wave whose amplitude is modulated (varied at an audio rate), and which travels through the other to a radio receiver.

What is slope detector?

FM slope detection is a concept that can used be recover the modulation from an FM signal. It is simple because it can be used with virtually any radio even if it is not equipped , with an FM capability. It simply uses the selectivity of the radio, or the slope of a tuned circuit.

What is FM detector?

FM detectors are circuits that instantaneously convert the frequency changes from the carrier signal to its output voltage counterpart. They are also known as frequency demodulators or discriminators.

What is the function of modulator?

A modulator is an electronic circuit that superimposes a low-frequency (information) signal onto a high-frequency (carrier) signal for the purpose of wireless transmission. The reason for this is that higher frequency signals can be received using shorter aerials, which are more practical than longer ones.

How does a BJT act as a switch?

How does a BJT act as a switch? A transistor has three modes: active region, cut off region and the saturation region. The transistor acts as a switch in the cut-off mode and the saturation mode. The transistor is fully off in the cutoff region and fully on the saturation region.

Which oscillator is used in a transmitter?

Crystal oscillators are the most common type of linear oscillator, used to stabilize the frequency of most radio transmitters, and to generate the clock signal in computers and quartz clocks.

Which is FM detector?

In any radio that is designed to receive frequency modulated signals there is some form of FM demodulator or detector. This circuit takes in frequency modulated RF signals and takes the modulation from the signal to output only the modulation that had been applied at the transmitter.

What is FM modulation and demodulation?

Frequency Modulation Tutorial Includes: FM demodulation is a key process in the reception of a frequency modulated signal. Once the signal has been received, filtered and amplified, it is necessary to recover the original modulation from the carrier. It is this process that is called demodulation or detection.

What are the two types of modulator?

These modulation techniques are classified into two major types: analog and digital or pulse modulation.

What are types of modulators?

Modulation techniques are roughly divided into four types: Analog modulation, Digital modulation, Pulse modulation , and Spread spectrum method. Analog modulation is typically used for AM, FM radio, and short-wave broadcasting.