Here is a FM radio circuit using
IC7400. IC TDA7000 is a monolithic integrated circuit for mono FM
portable radios, where a minimum on peripheral components is crucial.
The IC TDA7000 has a Frequency-Locked-Loop system with an intermediate
frequency of 70 kHz. The intermediate frequency selectivity is achieved
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 a mute circuit,
which also eliminates too noisy input signals. Special steps are taken
to meet the radiation requirements
• L1 and L2 wind 5 turns of 0.6 mm enameled Copper wire on a 4 mm dia plastic former.
IC TDA7000 Description
The
TDA7000 is a monolithic integrated circuit for mono FM portable radios,
where a minimum on peripheral components is important (small dimensions
and low costs).
The IC has an FLL (Frequency-Locked-Loop) system with an intermediate frequency of 70 kHz. The i.f. 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 a mute circuit, which also eliminates too noisy input signals. Special precautions are taken to meet the radiation requirements.
The IC has an FLL (Frequency-Locked-Loop) system with an intermediate frequency of 70 kHz. The i.f. 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 a mute circuit, which also eliminates too noisy input signals. Special precautions are taken to meet the radiation requirements.
Data IC TDA7000
Supply voltage range: 2,7 to 10 V
Supply current : 8 mA
R.F. input frequency range: 1,5 to 110 MHz
Sensitivity for -3 dB limiting
• (e.m.f. voltage)
• (source impedance: 75 Ohm mute disabled) EMF: 1,5 uV
Signal handling (e.m.f. voltage)
• (source impedance: 75 Ohm) EMF typ. 200 mV
A.F. output voltage at RL = 22 kOhm75 Mv
Supply voltage: max. 12 V
Oscillator voltage: 0,5 to VP0,5 V
Storage temperature 55 to 150 C
Operating ambient temperature 0 to 60 C.