Amplitude Limiter in FM Receiver: In order to make full use of the advantages offered by FM, a demodulator must be preceded by an Amplitude Limiter in FM Receiver, as discussed earlier, on the grounds…
FM Receiver Block Diagram: The FM receiver is a superheterodyne receiver, and the FM Receiver Block Diagram of Figure 6-28 shows just how similar it is to an AM receiver. The basic differences are as…
Indirect Synthesizer: Indirect Synthesizer: The required frequency range in most synthesizers nowadays is obtained from a variable voltage-controlled oscillator (VCO), whose output is corrected by comparison with that of a reference source. This inbuilt source…
Direct Synthesizer Block Diagram: A Direct Synthesizer Block Diagram is a piece of apparatus in which multiples and submultiples of a single crystal oscillator frequency are combined by addition and/or subtraction to provide a very…
Automatic Frequency Control Block Diagram: Automatic frequency control: As previously we see, the heart of an AFC circuit is a frequency-sensitive device, such as the phase discriminator, which produces a dc voltage whose amplitude and…
Squelch Circuit: Squelch (muting):Â When no carrier is present at the input, i.e., in the absence of transmissions on a given channel or between stations, a sensitive receiver will produce a disagreeable amount of loud noise.…
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 signals. Unfortunately, as Figures 6-14…
Communication Receiver Block Diagram: A Communication Receiver Block Diagram is one whose main function is the reception of signals used for communications rather than for entertainment. It is a radio receiver designed to perform the…
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 the changing strength of the…
Simple Diode Detector: Operation of diode detector: The Simple Diode Detector is by far the most common device used for AM demodulation (or detection), and its operation will now be considered in detail. On the…
