TDA7000 is a great chip because it includes RF input stage, mixer, local oscillator, IF (intermediate frequency) Limiter, IF filter, amplifier, Phase demodulator, Mute detector, Frequency-Locked-Loop system and voltage controlled oscillator (VCO) all in a single chip, so you don't have to do so much tuning and tweaking as you would normally do in super heterodyne receivers. TDA7000 is also a great choice for folks that don't have great experience with RF circuits due to the fact that there are few external capacitors & resistors needed, no external IF filters, and only one variable coil and varicap diode.
The IC has an FLL (Frequency-Locked-Loop) system with an intermediate frequency of 70 kHz. The IF selectivity is obtained by active RC filters. The only function which needs alignment is the resonant circuit for the oscillator, thus selecting the reception frequency.
Spurious reception is avoided by means of using a muting circuit similar to squelch. This eliminates and rejects other input signals around selected frequency so that even remote stations can sound clear just as if they were located near by.
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