Makers, developers and hobbyists that are looking to build different communication systems may be interested in a tiny open source digital walkie-talkie development board that is being launched several Kickstarter crowdfunding website.
The AVR RFM12 board has been created by Masih Vahida those looking to raise just $500 to take his concept into production which is based ATMEGA8 and the well known RFM12B RF module to send and receive voice communications.
Watch the video below to learn more about this interesting project and how you can help it make the jump into manufacture.
I used a popular and common RF module from HopeRF with the part number RFM12B which is a fast SPI data transceiver .
The most important thing in this project is, i get the analog signal that comes from the Micro Phone with AVR ATMEGA8A Micro Controller , convert the analog signal to the digital value with the internal ADC and then make data Packets and send the digital data packets through SPI port to the RF module.
On the receiver side, the RF Module receives the data , sends the Digital data through SPI Port to the micro controller and the micro controller will convert the Digital data to analog with the PWM output ! . yes PWM.
Because the data is digital , we are able to send data with the audio too and also we can change the carrier frequency or change the identification codes on each unit so we can set each groups with the same code or same frequency then the other units cannot receive data from the. it’s usefull when we want to use more than one group of walkie talkie and dont want to have interference.