Radio

Motorola RNet radios were wireless modem radios used for communication in the FIRST Robotics Competition from 1993 until the introduction of the cRIO control system and wi-fi communications in 2009. Rnet radios establish a wireless serial communications link similar to a dial-up modem but over-the-air instead of phone lines.

In the 1990s, teams would be supplied RNets in the kit of parts, but these were collected before the beginning of competition and teams were required to use a tether cable and tether adaptor, a 9-pin serial cable with a null-modem adaptor inserted to swap over the transmit and receive lines to connect the driver station to the robot controller.

Gallery

• Additional photos on the FRC Archive
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  A pair of the older metal-case RNet radios [1]
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  The tether cable and adaptor setup [2]
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  An IFI-cased modem radio [3]