Ok this is driving me crazy. I just got an AM21 to use with my HR34 and I can't get things to work. The AM21 has no menus or otherwise that come up on the HR34 so I don't know what the problem is. USB is plugged between AM21 USB and HR34 USB Antenna is plugged into AM21 Antenna Power is looped through AM21 and HR34 as required Have done Antenna set-up. Process completes. NO off air channels appear in guide Edit channels in Antenna set-up is always ghosted. I've tried multiple USB cables. I've tried off air digital antennas of different sizes and styles. Nothing, nothing, nothing. AM21 is so stupidly simple that it's almost impossible to figure out whats wrong. HR34 doesn't let you manually scan through channel. Or add all and then edit down. You can't do a signal strength on the off-air channels. HELP ! ! !