This is a “battery-powered Transistor FM Tracking Transmitter” that communicates a rehashing radio signal which can be recognized by a “directional antenna”. The transmitter communicates an isotropic (emanates in all directions) signal on the FM band.
A conventional FM radio can be utilized to detect the transmitter, the signal will improve when the radio antenna is pointed toward the transmitter. The circuit introduced here will transmit a sound tone in the FM band. The circuit can be utilized as the “tracking signal transmitter”.
Hardware Component
The hardware components required to make Transistor FM Tracking Transmitter are listed below:
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | DC Supply | 3V-6V | 1 |
| 2. | Antenna | 12 in | 1 |
| 3. | Trimmer Capacitor | 1-30pF | 1 |
| 4. | Coil | 2 Turns of #24 wire on 5 mm former | 1 |
| 5. | Capacitor | 1nF, 10nF, 2pF, 28pF, 5pF, 62pF | 1 |
| 6. | Resistor | 10Ω, 100Ω, 39K, 100K | 1 |
| 7. | Transistor | 2N2222, 2N3906, 2N3904 | 1 |
2N2222 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of 2N2222
2N3904 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of 2N3904
FM Tracking Transmitter Circuit
Working Explanation
In this part, we are discussing the circuit operation of a “Transistor FM tracking transmitter”. In this circuit, we are using a few low-cost components which are easily available in the market. Transistors of 2N3906, 2N3904, and 2N2222, resistors of 10Ω, 39K, 100Ω, and 100K, capacitors of 1nF, 28p, 5pF, 10nF, 62pF, and 2p, and trimmer capacitor of 1-30pF are the fundamental components of the circuit. This tracking transmitter circuit is worked around 4 transistors and execution is like the prior LM3909 tracking transmitter circuit. The circuit can be worked with 3 V to 6 V DC. The circuit has a decent transmitting range. Curl L1 is equivalent to 2 turns of #24 enameled wire twisted on 5mm previous. Utilize any 12 in the wire as an antenna.
Applications and Uses
- FM transmitters are used in fitness centers and vehicles.
- They are additionally used in places like halls.
