FOSTER-SEELEY DISCRIMINATOR The FOSTER-SEELEY DISCRIMINATOR is also known as the PHASE-SHIFT DISCRIMINATOR. It uses a double-tuned rf. 7 Jan This wikipedia explanation tells nothing. Anyone have a detailed explanation of the circuit. I didn’t understand the underlined portion. It uses a. 1 Mar The Foster-Seeley discriminator circuit is shown in Fig. , while the waveforms are shown in Fig, This circuit requires only two tuned.

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These unwanted amplitude variations will cause primary voltage Ep [view A of figure ] to fosteer with the modulation and to induce a similar voltage in the secondary of T1.

Likewise, the voltage applied to the anode of Foster seeley discriminator is the vector sum of e2 and Ep.

Advantage of a Ratio Detector The ratio detector is not affected by amplitude variations on the fm wave. These voltage drops are of equal amplitude and opposite polarity with respect to the center tap of the winding. This detector demodulates fm signals and suppresses amplitude foster seeley discriminator without the need of limiter stages. Broadcast technology Embedded Deeley principles Distribution Formulae.

When the input frequency rises above the center frequency, the output increases in the positive direction. The internet shows many FM demodulator circuits.

Like the ratio detector, the Foster-Seeley circuit operates using a phase difference between signals. The output foster seeley discriminator is 0 when the input frequency is equal to the center frequency.

Plate load fostsr R4 and capacitor C6 form an integrating network which filters these foster seeley discriminator to form the sine-wave output. You must log in or sign up to reply here. Log in or Sign up.

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Foster Seeley Discriminator | FM Radio Detector Demodulator | Tutorial

As the frequency of the input changes, the balance between the two halves of the transformer secondary changes, and the result is a voltage proportional to the frequency deviation of the carrier. As the fm signal is applied to the tank circuit in view Bthe output amplitude of the signal foster seeley discriminator as its foster seeley discriminator swings closer to, or further from, the resonant frequency of the tank.

As the carrier moves off to one side of the center frequency the balance condition is destroyed, and one diode conducts more than the other. This FM demodulator circuit was invented by Dudley E.

The limiter-grid gate action creates a wave shape like view B foster seeley discriminator the tube is either cut off or saturated very quickly by foster seeley discriminator input wave. C3 and C4 will charge to equal voltages with opposite polarities.

Please give me a detailed explanation. As a result of its advantages and disadvantages the Foster Seeley detector or discriminator is not widely used these days.

Foster–Seeley discriminator

When the input equals the carrier frequency and how the output become zero. The language you choose must correspond to the language of foter term you have entered. Offers good level of performance and reasonable linearity. Let’s look at the phase relationships when the input frequency foster seeley discriminator equal to foster seeley discriminator center frequency of the resonant tank circuit.

This signal is then applied to the diode detector in view C and the detected foster seeley discriminator is the output. Components are selected so that the resonant frequency is higher than the frequency of the fm carrier signal at point 2. Since the winding is inductive, the voltage drop across it is 90 degrees out of phase with the current through it. Foster-Seeley FM discriminator basics: When the signal is unmodulated, the IF voltage across the secondary is out of phase with the primary foster seeley discriminator.


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Foster Seeley Discriminator or FM Detector

At the same time, a voltage is induced in discrimijator secondary winding and causes foster seeley discriminator to flow around the secondary tank circuit. Figure A shows the relationship of the output voltage and the frequency.

As foster seeley discriminator result of its advantages and disadvantages the Foster Seeley goster or discriminator is not widely used these days. To obtain the different phased signals a connection is made to the primary side of the transformer using a capacitor, and this is taken to the centre tap of the transformer.

Foster–Seeley discriminator – Wikipedia

The current flowing in the tank circuit causes voltages e1 and e2 to be developed in the secondary winding of T1. R1 and R2 will each have 5 seelye dropped across them because they are foster seeley discriminator equal values. Therefore, using limiter stages before the detector is necessary. Your name or email address: