A Complete FM Radio on a Chip AN192

Page 10 of 11

Fig.16 A narrow band f.m. receiver with a crystall - controlled local - oscillator

Fig 17 I.F. Selectivity for the narow band f.m. receiver.

AUDIO AMPLIFIER AND DETUNING
INDICATOR CIRCUITS

Audio output stages suitable for use with the TDA7000 are shown in Fig. 18 and 19. Figure 20 shows how the muting signal can be used to o rate a LED to give an indication of detuning.

 

fig.18 A 0.4 mW transistor audio output stage without volume control for driving an earpeach