Product Demodulator: The Product Demodulator (or detector), as shown in Figure 6-44, is virtually a mixer with audio output. It is popular for SSB, but is equally capable of demodulating…

Stereo FM Multiplex Reception: Assuming there have been no losses or distortion in transmission, the demodulator output in a Stereo FM Multiplex Reception, tuned to a stereo transmission, will be…

Ratio Detector Circuit: In the Foster-Seeley discriminator, changes in the magnitude of the input signal will give rise to amplitude changes in the resulting output voltage. This makes prior limiting…

Slope Detector FM Demodulation: Consider a frequency-modulated signal fed to a tuned circuit whose resonant frequency is to one side of the center frequency of the FM signal. The output…

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…

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…

Squelch Circuit: Squelch (muting): 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…

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…