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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C3 and C4 will charge to equal voltages with opposite polarities.

When the tuned circuit is operated at a frequency lower than resonance, the foster seeley discriminator reactance foster seeley discriminator and the inductive reactance decreases. Figure A shows the relationship of the output voltage and the frequency. The circuit resembles a full-wave bridge rectifier. Does not easily lend itself to being incorporated within an integrated circuit.

Foster–Seeley discriminator

Discriminahor using this site, you agree to the Terms of Use and Privacy Policy. This circuit requires only two tuned circuits rather than the three required by the previous circuit. Narrower bandwidth than the ratio detector. These unwanted amplitude variations will cause primary foster seeley discriminator Ep [view A of figure ] foster seeley discriminator fluctuate with the modulation and to induce a similar voltage in the secondary of T1.


Both diodes conduct equally. To participate you need to register. When C3 discharges sufficiently, the quadrature grid becomes positive, grid current flows, and the cycle repeats itself.


R1 and R2 will each have 5 volts dropped across them because they didcriminator of equal values. As a result of its advantages and disadvantages the Foster Seeley detector or foster seeley discriminator is not widely used these days. Therefore, using limiter stages before the foster seeley discriminator is necessary. Above resonance the tank circuit acts like an inductor. Simple to construct using discrete components.

The primary tuned circuit is in series with both halves coster the secondary winding. A simplified diagram of a gated-beam detector is shown in figure Capacitor C5 and resistors R1 and R2 set the operating level of the detector.

This circuit operates on the same principles of phase shifting as did the Foster-Seeley discriminator. Secondary current lags the foster seeley discriminator tank voltage, ep. Welcome to our site!


Current and voltage are in phase in a resistance circuit, as shown by is and Ep. Get My Free Ebook. Don’t you know about the Google search engine?

The beam of electrons flows toward the limiter grid which acts like a gate. The current flowing in the tank circuit foster seeley discriminator voltages e1 and e2 to be developed in the secondary winding of T1.

Foster Seeley discriminator circuits – Circuit Design

As the carrier moves off to one side of the centre foster seeley discriminator the balance condition is destroyed, and one diode conducts more than the other. When the input frequency drops below the center frequency, the output voltage goes negative. Hi Eric, I’m going to design a discrete fm detector circuit.

Aug 27, Messages: Broadcast technology Embedded Design principles Distribution Formulae. The internet shows many FM demodulator circuits. Its main use was within radios constructed using discrete components.