On 1/11/2012 7:09 AM, sms88 wrote:
Of course the big problem is that in impaired conditions, at 10% power,
it would be difficult to even receive the HD signal. That's why it's so
important for radio stations to increase their digital power.

So now they're saying that even 10% power is impaired, huh? Gee. Why
don't we just turn the entire FM band into a bunch of digital haystacks?

Dave B.

On 1/11/2012 7:29 PM, SMS wrote:
IBOC is a temporary compromise. Eventually analog will be turned off and
HD Radio will be all digital.

I still haven't heard how you plan to allocate 400 KHz worth of digital
signal into a 200 KHz assigned FM channel. How does that work again?

Dave B.

On 1/12/2012 3:43 PM, Dave Barnett wrote:
On 1/11/2012 7:09 AM, sms88 wrote:
Of course the big problem is that in impaired conditions, at 10% power,
it would be difficult to even receive the HD signal. That's why it's so
important for radio stations to increase their digital power.

So now they're saying that even 10% power is impaired, huh? Gee. Why
don't we just turn the entire FM band into a bunch of digital haystacks?

Dave B.

No, my mistake, I meant to say "at 1% power..."

On 1/12/2012 3:48 PM, Dave Barnett wrote:
On 1/11/2012 7:29 PM, SMS wrote:
IBOC is a temporary compromise. Eventually analog will be turned off and
HD Radio will be all digital.

I still haven't heard how you plan to allocate 400 KHz worth of digital
signal into a 200 KHz assigned FM channel. How does that work again?

Dave B.

I think you're well aware of the answer. Not every FM station will be
able to use 400 Khz. Some can have only one sideband at maximum power. A
small percentage can't use either sideband. Life is rough when you're
trying to maximize spectral efficiency.

On Thu, 12 Jan 2012 12:09:37 -0800, SMS
wrote:

It's nearly four years old, but since the satellite radio providers
obviously don't want to talk about bit rates, it'll have to do.

Actually, I'm not all that interested in bit rate. What methinks is a
problem is the error rate. You could be running the full 64Kbits/sec
per channel, but with a sufficiently high uncorrectable error rate,
the quality will suck. FEC helps, but isn't a cure all. Same problem
with HD Radio. It's difficult enough to find the data rate without
ripping open the receiver and probing the guts. Getting the error
rate is even more difficult.

It's
pretty clear where the complaints of audio quality on satellite are
coming from.

Ummm... the complaints are coming from listeners. Should they be
coming from elsewhere?

... obviously there are many consumers for whom audio
quality is of minimal importance.

I guess that includes me. You wouldn't believer the OTA FM noise I
have to tolerate. Driving through the hills, the stations alternately
appear and disappear. In between the radio just belches noise. Trying
to hear anything over the road noise, scanner, and 2way radio noise is
difficult. Meanwhile, the GPS mapping display is yelling at me to
turn here and there. At the same time, my Droid is mumbling something
about email and reminders. Even if the music were distortion free, I
probably wouldn't notice.

On long trips we like to listen to audio books, and most libraries have
a very good selection.

Well, they've passed laws against driving while talking on the phone.
Perhaps the next step is to pass a law against driving while listening
to audio books. It's too much of a distraction for the GUM (great
unwashed masses).

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com
# http://www.LearnByDestroying.com AE6KS

On 1/12/2012 6:47 PM, Jeff Liebermann wrote:
On Thu, 12 Jan 2012 12:09:37 -0800,
wrote:

It's nearly four years old, but since the satellite radio providers
obviously don't want to talk about bit rates, it'll have to do.

Actually, I'm not all that interested in bit rate. What methinks is a
problem is the error rate. You could be running the full 64Kbits/sec
per channel, but with a sufficiently high uncorrectable error rate,
the quality will suck. FEC helps, but isn't a cure all. Same problem
with HD Radio. It's difficult enough to find the data rate without
ripping open the receiver and probing the guts. Getting the error
rate is even more difficult.

It's
pretty clear where the complaints of audio quality on satellite are
coming from.

Ummm... the complaints are coming from listeners. Should they be
coming from elsewhere?

... obviously there are many consumers for whom audio
quality is of minimal importance.

I guess that includes me. You wouldn't believer the OTA FM noise I
have to tolerate. Driving through the hills, the stations alternately
appear and disappear. In between the radio just belches noise. Trying
to hear anything over the road noise, scanner, and 2way radio noise is
difficult. Meanwhile, the GPS mapping display is yelling at me to
turn here and there. At the same time, my Droid is mumbling something
about email and reminders. Even if the music were distortion free, I
probably wouldn't notice.

On long trips we like to listen to audio books, and most libraries have
a very good selection.

Well, they've passed laws against driving while talking on the phone.
Perhaps the next step is to pass a law against driving while listening
to audio books. It's too much of a distraction for the GUM (great
unwashed masses).

With HD Radio if signal strength is too low (error rate too high) it
simply won't lock on to HD.

On 1/12/2012 5:26 PM, SMS wrote:

I think you're well aware of the answer. Not every FM station will be
able to use 400 Khz. Some can have only one sideband at maximum power. A
small percentage can't use either sideband. Life is rough when you're
trying to maximize spectral efficiency.

In fact a very small percentage will be able to use 400 KHz at their
assigned frequencies. We had this discussion once before, since the
Ibiquity spec posted he

http://www.nrscstandards.org/SG/NRSC-5-B/1026sE.pdf

shows double the occupied bandwidth for a digital signal.

You said that most stations are spaced far enough from their
adjacent-channel neighbors that this wouldn't be a problem, despite
numerous examples of adjacent-channel interference right here in the Bay
Area. The fact is that this would work somewhat in the plains of
Western Nebraska, but never in the Bay Area. Moving just one station
has a severe domino effect. Let me give you an example of one such
situation right here in the Bay Area:

The South Bay will soon have a full-power FM station on 93.7. Why?

93.7 KXZM in Felton will be increasing power. Why?

KXSM in Hollister is moving from 93.5 to 93.1 and increasing power. Why?

KOSO in Patterson moved from 93.1 to 92.9 and decreased power. Why?

So 93.1 KHLX in Pollock Pines could move their transmitter closer to
Sacramento.

How did Pollock Pines get a radio station? Somebody bought a radio
station in Susanville and moved it to Pollock Pines.

This is just one example of how tightly sandwiched signals are
throughout the US. A transaction in Susanville has an effect on the Bay
Area. Spacing is already so close that adjacent-channel HD interference
is very obvious to those who know what it is. Those who don't know the
difference between regular static and digital noise just turn off their
radio. That is why those of us who care about the real future of
broadcasting and know how to use a spectrum analyzer would like to see
the Ibiquity scheme just go away and be replaced with a truly viable
digital radio medium.

Dave B.

On 1/12/2012 10:49 PM, Dave Barnett wrote:
On 1/12/2012 5:26 PM, SMS wrote:

I think you're well aware of the answer. Not every FM station will be
able to use 400 Khz. Some can have only one sideband at maximum power. A
small percentage can't use either sideband. Life is rough when you're
trying to maximize spectral efficiency.

In fact a very small percentage will be able to use 400 KHz at their
assigned frequencies. We had this discussion once before, since the
Ibiquity spec posted he

That's why the industry is pushing for asymmetric sidebands. 200 KHz is
a compromise when 400 KHz isn't feasible.

It's absolutely vital to the future of terrestrial radio to move to
digital broadcasting. It's the only way to remain a relevant choice.
We're not talking about radio enthusiasts, we're talking about the mass
market which matters to broadcasters.

On Fri, 13 Jan 2012 06:25:59 -0800
SMS wrote:
It's absolutely vital to the future of terrestrial radio to move to
digital broadcasting. It's the only way to remain a relevant choice.

Oh BS. The average radio listener doesn't give a rats arse what medium its
on so long as the content is good and it sounds reasonable. And for speech
radio AM is perfectly satisfactory.

If music radio stations want to know why they're slowly haemoraging listeners
perhaps they should listen to the computer generated playlist drivel they
pump out occasionally.

B2003

On 1/13/12 3:25 PM, SMS wrote:
It's absolutely vital to the future of terrestrial radio to move to
digital broadcasting. It's the only way to remain a relevant choice.
We're not talking about radio enthusiasts, we're talking about the mass
market which matters to broadcasters.

Listeners are perfectly happy with the technical side of things. When FM
radio started, stations knew... it is content that the people are going for.

So if stations worry about their future they should worry about content.

gr, hwh