Four Stage FM Transmitter project is designed for the users to read the MP3 stored in a Pen drive and to transmit the audio through FM transmitter. It also transmits the audio signal from the microphone.
It mainly consists of Microphone, USB connector, USB reading IC, audio pre amplifier circuit, FM transmitter etc.
As soon as the pen drive is connected in the USB, the USB IC reads the MP3 data in the pen drive.
The MP3 data is converted into audio signal by means of pre amplifier stage. This signal is given to the FM Transmitter unit through N/O contact of a DPDT switch.
The signal from the microphone is converted into audio signal by means of mic pre amplifier. This signal is given to the FM transmitter unit through N/C contact of the DPDT switch.
The user can watch the MP3 and also the audio from the microphone in wireless manner.