Short spaced TV stations...

[old_tv_nut]

During the phase-in of ATSC, there were precise offsets applied to minimize interference into analog stations. This was needed because of ATSC's use of a pilot carrier near the lower edge of the 6 Mhz channel. Offsets were controlled not only for co-channel, but anylowe r adjacent NTSC channel as well. ATSC 3.0, like DVB, uses COFDM, with multiple pilots at the same level as data scattered over the band, so the signal is very noise-like and no visible pilot beats would appear in an analog set. Of course, precision lock between ATSC transmitters is required if they are part of a single-frequency network (use of multiple transmitters to cover an area with a single broadcast on the same frequency), just as it is/would be with DVB.