Agree with Dazzler. In the main screen display, down in the right-hand corner at the bottom, are two boxes. One shows the mode you are in - HRS, PCM, PPM - and the other shows if your are on the display (DISP) or transmitting modes (RF).
Make sure that the left hand box shows 'RF', then you are transmitting - follow Dazzler's instructions above. If you are on the Futaba FASST system the right hand one should show HRS. I don't know what mode you would need for a Spektrum - check your instructions. To change the mode go to Menu 3, scroll down to 'MOD-MODE', select it and then change the mode to HRS for FASST. Select the right one for Spektrum there too.
HTH. Come back if any of the information above is not clear.
