jras20 said:
The side adjustment channels is what gets me the most about HD Radio. I think if HD Radio can figure out how to change that then it will work a lot better. My place just south of Austin, I am only 15 miles away from KBPA. Their HD got knocked out last night by KOUL. Is there any way HD can fix that if they boost the power? There are pretty good choices now in Austin for HD. I'm almost thinking of getting a JVC HD Receiver for my truck.
I think you mean "Adjacent Channels." I agree, that they are "the" big problem, but don't hold your breath for them to go away. They are an integral part of the IBOC system. Without them, there is no HD radio. What’s more, they will probably get worse. The HD Alliance and NAB have petitioned the FCC to allow them to have as much as a 10 db increase in those adjacent channel sidebands on FM channels. That means multiplying the HD power by a factor of 10. In other words, a 1000 watt digital signal becomes a 10,000 watt digital signal. If there is a little noise right now, wait until you hear this.
The good news is it will be massively expensive to make a 10 db leap. Depending on the method chosen to do this, it may well be beyond the budgets of all but the biggest broadcasters. Perhaps, that is the plan. It may require upgrading your analog transmitter as well as purchasing a new digital transmitter, maybe installing a new antenna, new combiners, huge dummy loads, etc. It is not just a one time expense either. In many cases it will require upgrading electric service to the transmitter site, replacing standby generators and increasing air conditioning load capacity. Once this is in place, stand by for some impressive increases in your electric bill. If you don't own your own tower, you could expect tower rent to increae as well.
Since most broadcasters consider this to be a business, many will quickly get the message that it is simply not worth the cost to implement such a huge power increase. I suspect that most will settle for a more modest increase, or perhaps none at all. When they put a pencil to it, they will see that for the foreseeable future, it has a very poor chance of being a good investment. Return on Investment (ROI) is a basic of every business decision.
Assuming a power increase is approved by the FCC, and I suspect it will be, you can look forward to more interference on the FM band. Look on the front cover of Radio World magazine of a couple of weeks ago for a very visual example. It shows the potential interference patterns of two DFW FM stations. This proposed power increase effectively blocks reception of those two stations for about 500,000 potential listeners. That was just two stations out of the 60 or so that are receivable in the DFW area. Just think what it would be like if everyone did this?
A power increase of this magnitude has the potential to turn a 100,000 watt FM into a much more local station than anyone ever imagined.