Gadget Download

Notice Board is primary thing in any institution / organization or public utility places like bus stations, railway stations and parks. But sticking various notices day-to-day is a difficult process. A separate person is required to take care of this notices display. This project deals about an advanced hi-tech wireless notice board.

Matrix type display is designed using 5mm LED on a printed circuit board. A driver circuit is designed to drive all these LEDs. A GSM/CDMA Mobile Can is used to enter the required text or notice. The scrolling speed of the text also can be changed according to user requirement.

                                

After entering the text the SMS is sent to the no which is connected to the LED display. At any time the user can add or remove or alter the text according to his requirement.

At the receiving end the GSM modem which is connected to the Max 232 receives the message and is connected to the microcontroller AT89S52. The message which is already stored in the EEPROM is displayed on the LED Display.     

This project uses regulated 5V, 500mA power supply. 7805 three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac out put of secondary of 230/12V step down transformer.