You need to tether the OI and the RC together at least once after you have your team number with the dip switches (in binary) on the OI.
Once tethered it programs the team number in the board. Once that is done you are able to use the radios.
But, sometimes it's just easier to use the tether cable for early testing.
most of what you need to know is on
http://www.ifirobotics.com/