Frequency modulation is utilized in a radio station in the 88-108MHz VHF band. This data transfer bandwidth range sets apart from FM on the band sizes of radio receivers. And the devices that can get such signals are called FM receivers.
Here, LM386 and TDA7021 audio amplifier ICs are utilized to receive the sound signals. The 9018 signal amplifier IC is additionally deployed to support the IC. The FM radio transmitter is working on a 200kHz wide channel. The most extreme sound frequency transmits in FM is 15 kHz which is 4.5 kHz in AM. This permits a lot bigger scope of frequency moves in FM and accordingly, the quality of FM transmission is essentially higher than that of AM transmission.
Hardware Components
The following components are required to make an FM Receiver Circuit
| S.no | Components | Value | Qty |
|---|---|---|---|
| 1. | IC | LM386 | 1 |
| 2. | IC | TDA702IT | 1 |
| 3. | Transistor | 9018 | 1 |
| 4. | Antenna | – | 1 |
| 5. | Headphones | – | 1 |
| 6. | Variable Capacitor | 25pF | 1 |
| 7. | Resistor | 22K, 2.2K, 4.7K | 1, 1, 1 |
| 8. | Capacitor | 51pF, 220µF, 10µF, 4700pF, 220pF, 1000pF, 3.3nF, 100nF, 10nF, 100pF | 1, 2, 2, 1, 1, 1, 1, 3, 2, 1 |
| 9. | Battery | 3 Volts | 1 |
TDA702IT Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of TDA702IT
LM386 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of LM386
FM Receiver Circuit
Working Explanation
Here is a convenient quality sensitive FM recipient circuit or FM tuner circuit. The circuit works around the TDA 7021T IC which is an FM radio receiver IC. The IC requires just barely any external parts and the necessary voltage is just 3 volts. The sound yield is low so we have further amplified it with LM386 amplifier IC. You can likewise utilize other high-power sound speakers with it to expand the sound more. A high-frequency tune antenna speaker circuit utilizes the antenna input segment of the circuit for expanding affectability. You can change the recurrence with the assistance of a 25pF variable capacitor. The Coil L1 is an air-cored coil equivalent to 5 turns of 1mm silver plated wire turned on a 4mm composition.
This FM radio circuit is entirely versatile and easily fits in a little box with batteries.
Applications and Uses
- FM receivers are generally used in fin FM radio telecom.
- It is likewise used in seismic prospecting, telemetry, radar, and monitoring newborns for seizures through EEG, music synthesis, two-way radio systems, some video-transmission frameworks, and magnetic tape recording systems.
