Doppler effect would reduce both the emission interval as well as the radio frequency. Not to mention that an object (which is comparatively close to us, i.e. n

Doppler effect would reduce both the emission interval as well as the radio frequency. Not to mention that an object (which is comparatively close to us, i.e. not just red-shifted due to distance) would have to move at very close to the speed of light to be red-shifted that much. Now that would be unlike anything we've seen before...