A Stable FM transmitter provides stable undisturbed output frequency even when the battery drains out. Therefore, this project gives a detailed description of how to make a stable FM transmitter by using the LM2936 regulator. This is a stable, and harmonic-free FM transmitter that can be used for a wide range of FM frequencies.
Furthermore, the circuit described here is one of the amazing techniques to make a stable FM transmitter that utilizes the LM2936 voltage regulator IC. LM2936 helps to provide accurate voltage to the oscillator which results in the transmitter’s frequency stability. The circuit utilizes a 2N3904 transistor along with a regulator to amplify the input voltage and enhance stability.
Hardware Components
The following components are required to make a Stable FM Transmitter Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | IC | LM2936 | 1 |
| 2. | Transistor | 2N3904 | 1 |
| 3. | Antenna | 12 inch | 1 |
| 4. | Electret Mic | – | 1 |
| 5. | Inductor | – | 1 |
| 6. | Variable Capacitor | 1 – 35 pF | 1 |
| 7. | Ceramic Capacitor | 0.1µF, 10nF, 5pF | 1, 1, 1 |
| 8. | Resistor | 5.5kΩ, 1kΩ, 10kΩ | 1, 2, 1 |
| 9. | Battery | 9 – 12V | 1 |
| 10. | Electrolytic Capacitor | 10µF, 0.47µF | 1, 1 |
LM2936 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of LM2936
Stable FM Transmitter Circuit
Working Explanation
The working clarification of the circuit is simple and straightforward. In like manner, the circuit is using LM2936-5.0 IC which is considered as a fixed 5 volts low dropout positive voltage controller. Besides, this LM2936 IC gives stable 5 volts to the transmitter until the battery gets down to 5.2 volts. Utilize a 12-inch antenna device with the circuit. For more frequency ranges utilize a 30-inch radio wire or use DIY FM receiving wire for accomplishing long range with this circuit.
Applications and Uses
- It can utilize as an RF signal generator
- It can likewise be utilized to provide stable frequency signals even when the battery is almost drained out
- Provides stability in the signal voltage
