Model no: 23 The outline of the project is that the text message typed using a computer keyboard attached to a microcontroller to be sent, is encrypted by using an appropriate program with LCD display and then the encrypted message is transmitted through wireless using Radio frequency transmitting Module. At the receiver end the signal is received by the RF receiver module and the analog signal is converted to digital form. It is fed to another Microcontroller where it is decrypted by the program and the message is then displayed over the receiver LCD display.
The power supply consists of a step down transformer 230/12V, which steps down the voltage to 12V AC. This is converted to DC using a Bridge rectifier. The ripples are removed using a capacitive filter and it is then regulated to +5V using a voltage regulator 7805 which is required for the operation of the microcontroller and other components.