Check the battery life of the radio (single press the power button). If the radio is below 15% battery life, the battery is too low to transmit and can only receive signals.If the battery is not low, double check that the radio you are trying to talk with is on the same channel. Next, make sure the radio you are trying to transmit with is on the same privacy code. You will see CT lit up if privacy codes are activated, and can check the number of privacy code by double pressing the power button.