I also put together, on the same order (yhst-17210252890263-117133), a Dynam DC-3 Skybus. I had better luck with that one. I wonder if changed the crystal in the Sybus's 4chan Tx with the crystal in the Hawk Sky Tx would it give me a clue as to the problem. Are the crystals in the Dynam Tx's removable? The Hawk Sky is 72.830 and the Skybus is 72.150. If they are interchangeable it might tell me if there is a bad Tx with the Hawk Sky, right? You can let me know when you get a chance. Thanks for your help, Mark