Engineering Radio checked in with a word or two on the problem HD radio has interfering with its analog signal:
Self interference, new IBOC feature!
Far better than I could ever explain it, Dave Hershberger, of Continental Electronics explains some of the potential problems with increasing the IBOC carrier(s) in an FM HD Radio system. If you have not already read it, read the entire article, it sheds some interesting light on the IBOC system and how it works.
Transmitting more digital power will certainly increase the digital coverage area and reduce digital dropouts. However, there may be some unintended consequences, which every broadcaster will have to evaluate before increasing digital power.
It is all right there. What amazes me is that the IBOC proponents do not acknowledge the system’s problems. Perhaps the above article is a bit over the head of the average general manager, or group VP, whatever the title dejour is. Engineers should understand this. Engineers should be able to explain this in an understandable way to managers and owners. It is the owners or whoever is holding their paper that have the most to loose in this scheme, which is to say, everything. Forget the FCC, they are in the pockets of their corporate sponsors anyway. Radio station owner’s and the bankers that control them should take a real hard look at this and see for themselves that they are writing their own epitaph.