So how did that affect antenna design?
It allows UHF antennas to be designed to cover a narrower bandwidth since they don't have to cover 51-69. A good example is the DB line of antennas from Antennas Direct. Each model was resigned to peak reception at channel 51 instead of the old designs which peaked up at or above 69. The net effect is that the peak gains within the current UHF band is anywhere from 1 to 3 dB higher than the old model would have offered at the same channel.
But how will the upcoming spectrum auction and the repacking affect things?
No one knows if it will even happen. Commercial broadcasters have been saying "No thanks" in droves. The FCC already postponed the first reverse auction by a year.
Will there be many more VHF stations after the repacking?
Under the law as passed, broadcasters cannot be forced to VHF. Of course, given this president's penchant for ignoring laws and ruling by his own pen, that provision of the law probably isn't worth the paper it's written on.
I read recently that in NYC and Philadelphia Me-TV is going to be carried on RF 3 and RF 2, respectively, starting this year.
Unrelated to previous discussion, they're going to low power stations who agreed to carry them.
How doggone big does an antenna have to be to receive RF 2 and RF 3 at a distance of, say, 30 to 40 miles?
Depends on how much juice is pushing the signal. For a 300 watt LD station, it might not be possible with any antenna. A full-power station might require an antenna 8-10' wide and at least 5-10' long.Edited by ProjectSHO89 - 2/16/14 at 5:48pm