ya check the crystals is both your Transmiter and the Reciever!! If the numbers are the same, while your radio box is apart to check the Rx crystal, make sure all the wires are snugg and in the right spot, and last but not least if none of that solves the problem stick a voltmeter on the connection between the battery pack and the Reciever!! If none of this works take it back to where you got it, and see if they have any ideas, but the only things it could be is, the xtals dont match, the batteries are to low, the wires are crossed, or you have a defective system that needs replaced.