The device where the codes are actually located is what determines IR or RF transmission. In other words, a hidden device with the name of RF Codes could be set to RF, all pages within this device will then transmit RF, assuming this is the device where the codes were learned, or chosen from the database. The cable box device (for example) would have buttons with links to the hidden RF Codes device. In this case it wouldn't matter what the cable box device was set for, it would always send RF due to the properties of the RF Codes device.

Hope this makes sense.