Why is ATSC on VHF so damn finicky?

[pgnl]

It will be interesting to learn whether or not ATSC 3.0 NextGen TV improves the situation. My understanding is ATSC 3.0 uses COFDM with multiple carriers unlike VSB in ATSC 1/2. In the UK DVB-T and DVB-T2 uses COFDM, the former with up to 8000 carriers and the latter with up to 32000 carriers, presumably this method evens out and helps eliminate interference. DVB-T was first used in the UK for SD in 1997 and DVB-T2 for HD in 2010.

I remember reading when ATSC was adopted and chosen over DVB-T, that broadcast conditions in the US are very different and over longer distances to many other countries, which presumably why it was selected - in addition to of course the US wanting to use its own developed system.

I have never actually seen an ATSC HD picture, but assume like DVB-T2 with HD it is pretty rock solid. Someone mentioned MPEG2 artifacts, the UK uses MPEG2 for SD on DVB-T and MPEG4 for HD on DVB-T2. Germany broadcasts HD/UHD using HEVC on DVB-T2..

Patrick, UK