Transmitter Circuit

The purpose of the transmitter circuit is to send the conference room information to the receivers at each conference room. It connects to the serial port of a PC and works in conjuction with software that is running on the computer. Whenever the circuit receives data over the serial port, it will convert the signals to TTL values and then send them using the RF transmitter. The data is sent at a baud rate of 2400.

The transmitter circuit can be implemented one of two ways. The schematic provided shows the low power version allowing the entire circuit to be run off of the power from the serial cable. Some serial ports will not have enough power to run the transmitter. In this case you could just add power to the board and leave it as is or you can use the LT1130CN chip to convert the serial cable data for the transmitter.

The source code for the Windows application that uses the transmitter is found here.

A complete parts list for the transmitter circuit can be found here.