Skywave propagation is a combination of physics and science. Unless (and it's been tried time and time again) someone invents an AM antenna that totally suppresses skywave, there is no "solution"... just facts.[/FONT]
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AM All Digital Test Results
- Thread starter Kelly A
- Start date
Skywave propagation is a combination of physics and science. Unless (and it's been tried time and time again) someone invents an AM antenna that totally suppresses skywave, there is no "solution"... just facts.[/FONT]
So this subject is mute, It won't happen at all
Combine that with the decreasing sunspot numbers as Cycle 24 slowly comes to an end. This will make propagation on the AM and lower SW bands much better in the coming years. Cycle 24 should bottom out sometime in 2019 or '20, with great conditions on the AM band in the winter months.
Kind of like the predictions back in the 50's and 60's that nobody would ever listen to FM broadcasts?
Making FM go "all digital" would be an incredible FM radio band killer. First -- it's not needed. FM already had HD that works reasonably well. Second, it would make the vast majority of the car radios right now absolutely useless.
They would immediately slough off probably 90% of their audience who listen on Analog FM radios.
Making AM go all digital right now would kill AM -- but if they allowed some stations to go all digital, who knows? It might keep the AM band viable long term as more HD / Digital radios are installed in cars, and more listeners take a chance on hearing their favorite programming on the AM band in HD.
The problem is the home and work listening, which may or may not be done on computers or tablet devices (perhaps one of the experts knows these numbers?).
As for skywave, RFI interference on AM, etc. -- we have that already. Those who listen listen, and those who won't put up with any interference already switch off their radios or listen to FM. I don't see how all-digital AM would make it any different in that respect. I don't have a digital capable AM radio but the two local AM stations with IBOC have strong enough buzzing on my analog radios I'm certain that they would come in quite well in HD at my location -- RFI or no RFI.
They would immediately slough off probably 90% of their audience who listen on Analog FM radios.
Making AM go all digital right now would kill AM -- but if they allowed some stations to go all digital, who knows? It might keep the AM band viable long term as more HD / Digital radios are installed in cars, and more listeners take a chance on hearing their favorite programming on the AM band in HD.
The problem is the home and work listening, which may or may not be done on computers or tablet devices (perhaps one of the experts knows these numbers?).
As for skywave, RFI interference on AM, etc. -- we have that already. Those who listen listen, and those who won't put up with any interference already switch off their radios or listen to FM. I don't see how all-digital AM would make it any different in that respect. I don't have a digital capable AM radio but the two local AM stations with IBOC have strong enough buzzing on my analog radios I'm certain that they would come in quite well in HD at my location -- RFI or no RFI.
The recent tests of full digital AM seems to indicate that reception of an all digital signal is much more immune to terrestrial noise than the analog signal. With digital mode, either your receive the audio or you don't. There is no noise floor.
How about the Interference Problem like TV's, Computers, Light Bulbs. ect on AM
How will the FCC figure that out?
How will the FCC figure that out?
Has nothing to do with the FCC, nor am I suggesting the FCC mandate full digital AM. Consumer product manufacturers have been ignoring Part 15 noise requirements for years. Nobody's going to start enforcing it now. If broadcasters want to take the chance, as they did with FM licenses back in the 60's, playing the long game, under-performing AM stations within a group going to all-digital may be an interesting option.
It seems to me that having a modulation method that is more tolerant of any sort of terrestrial noise over analog reception, thus potentially giving the AM band an actual future, is a good thing. AM broadcasters have an opportunity to change their future or ignore it at their own peril.
Let me propose another idea, one that I believe would require an FCC rule change.
Permit AM stations in hybrid mode to have separate programming on their analogue channel and their digital channel.
Why, for example, should an AM station not be able to run their current news/talk/sports format in analogue,
while introducing a unique music offering in digital, which is supposed to have FM-like audio quality?
Permit AM stations in hybrid mode to have separate programming on their analogue channel and their digital channel.
Why, for example, should an AM station not be able to run their current news/talk/sports format in analogue,
while introducing a unique music offering in digital, which is supposed to have FM-like audio quality?
Why would it require a rule change? I thought that's what stations are doing now.
AM stations in hybrid mode are universally duplicating their analogue audio in digital.
I am unsure whether this is legally mandated, but I believe it might be, as all FMs duplicate their analogue on their HD1's.
Two challenges: Hybrid mode on AM does neither mode well and takes up bandwidth that compromises the digital signal reception. That's why besides full digital mode seeming more robust, provides superior audio quality, and because the modulation is RMS rather than peak-reliant, fringe area coverage is superior over analog.
Big A is correct, there were never any rules that prohibited an AM broadcaster doing IBOC on AM from running alternate programming analog or digital. The Commission doesn't get involved in programming.
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The HD-1 (FM) and HD (AM) signals must simulcast the analog signal.
Is that an FCC rule or an IBOC licensing issue?
That is the way it was designed by iBiquity (and its predecessors) and approved for use by the FCC.
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So all the old AM Analog Radios will be usless, including Car Radio if this goes though
Which is why it hasn't happened so far, and why it won't happen at all. The FCC has no reason to approve.
These tests are all about the radio industry trying to build support, but it won't matter.
They were talking about analog and digital co-existing on the same band. At some point, they won't need to, assuming all digital takes off. An argument could be made that in some parts of the country, AM is fast approaching uselessness!
Bingo! And why I believe the Commission would probably allow stations that are willing to take the gamble of going all digital, to do so.
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