We've had a half dozen different antennas on that tower and still didn't have enough signal to lock the channels.
Amplified signal? I've never used an amplifier. Not amplified--there's a tremendous loss of signal over 60', personal experience. Which is why I say try bringing an antenna closer to the viewing equipment, even if tens of feet lower than 60'. My personal experience is something like more than 50' of coax with a small 2-bay antenna equals no signal on otherwise Strong broadcasts. Shortening the coax equaled steady reception of even Moderate broadcasts.