In this tutorial, we are developing a project for a “Wireless FM transmitter circuit”. Here is a decent long-range FM transmitter circuit with a few parts that will give a good outcome. This FM RF transmitter circuit has two phases first oscillator phase and the second RF amp phase. A Wireless FM transmitter is a “low-power FM radio transmitter” that communicates a signal from a portable audio device to a “standard FM radio”.
Hardware Components
The following components are required to make a Wireless FM transmitter Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | Antenna | 12 in | 1 |
| 2. | Transistor | 2SC9018 | 1 |
| 3. | Ceramic Capacitor | 1000uF, 68pF, 36pF, 6pF | 1, 1, 1, 2 |
| 4. | Electrolytic Capacitor | 0.047 µF | 1 |
| 5. | Resistor | 4.7K, 36K, 100Ω, 120Ω | 1 |
| 6. | Mic | – | 1 |
2SC9018 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of 2SC9018
Wireless FM Transmitter Circuit
Working Explanation
Transistor Q1 is filling in as an oscillator and Q2 is functioning as an RF power amplifier. The circuit won’t change its frequency by contacting the antenna as a result of Q2 which is isolating the antenna from the oscillator. L1 and L2 are equivalent to 10 turns of 1mm enameled wire close twisted on a 3mm structure.
Try not to make any holes between the turns of the loop. The trimmer capacitor C4 is to change the frequency and C5 is to coordinate the oscillator to the RF amplifier stage. Adjusting the output by changing C5 is critical to getting full yield from the circuit, you need to utilize a “field strength meter” to change the C5 for the greatest yield.
The antenna will be a 30-inch wire or you can likewise utilize a 12-inch antenna in the event that you need it. Using a 12-inch antenna will diminish the scope of the transmitter. The most extreme range with the 30-inch antenna will be 2 km or more in the open section.
Applications and Uses
Wireless FM transmitter is generally used for playing audio gadgets on vehicle radios and broadcasting stationary audio on PCs and Television etc.
