David Eduardo wrote:
Most stations don't care today about anything except their home metro
groundwave coverage. Any damage in the secondary or skywave coverage areas
is irrelevant.

Maybe not to the listeners who live in such areas?

There are areas where all nighttime AM service is secondary - where no
AM station provides primary service. My location is nearly one of them;
the only station providing primary nighttime AM service is WSM. It is
not difficult to find a place in Tennessee beyond WSM's primary coverage
where there is *no* nighttime primary service - my guess is several
hundred thousand people in Tennessee alone live in such areas.

Certainly these people aren't a majority, but there are a *bunch* of
them out there - and they have Congressmen. Will these people complain
to their representatives when their AM service disappears? Or is AM so
irrelevant to most listeners that they won't care - or even notice?
--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com

"David Eduardo" wrote in message
...

There is also some evidence that IBOC interference can affect home
metro groundwave coverage of adjacent channel stations.

But not much. I can listen to the 1050 in the Riverside market within 10
miles of the 1020 KTNQ 50 kw IBOC site.

Yeah, but Riverside is in KTNQ's null - where their day pattern has the
equivalent of about 6kW, NOT 50kW. The KTNQ day pattern runs 6kW or less
over most of the ESE quadrant. They have far less toward Riverside at night.
And Riverside is in the max of 1050's day pattern.

Presumably the 1020 IBOC pattern is proportional to the main signal's
pattern.

30 kHz spacing and 6 kW doesn't sound like a severe test to me.

On 14 Jun 2004 04:22:21 GMT, "David Eduardo"
wrote:


But you are concened about the damage to the local signal, not the abilty to
hear an AM hundreds of miles form its city of license.

With 5kw we're not expecting a usable signal hundreds of miles away
from the COL. But we are concerned about more than our metro coverage
area.


There is also some evidence that IBOC interference can affect home
metro groundwave coverage of adjacent channel stations.

But not much. I can listen to the 1050 in the Riverside market within 10
miles of the KTNQ 50 kw IBOC site.


I certainly hope so, since they are 30 kHz apart. But there is a real
problem with first-adjacent channel interference. I reference a
statement submitted by Clear Channel SVP/Engineering Jeff Littlejohn
to the National Radio Systems Committee regarding a test involving
WTOP, Washington (1500) and WARK, Hagerstown, MD (1490). Daytime
interference from WTOP's digital signal was found to be "significant"
at WARK's protected 0.50 mV/M contour, and "noticeable" at its 0.75
mV/M contour.
The full report can be found at
http://www.am-dx.com/clearchannelrprt.pdf

Mark Howell

David Eduardo wrote:
"Scott Dorsey" wrote in message
...

IBOC FM is a mixed bag. It doesn't sound all that wonderful, but again
I think most of the FM sound quality issues have to do with overprocessing
more than anything else, and digital transmission doesn't do anything
about
that.

I am "in the building" with one of these, and on the available receivers, FM
IBOC has definite advantages, one you realize you are hearing audio without
the preemphasis curve we are used to hearing on FM. That done, it sounds
better to everyone who has heard real-world music programming on it.

Run that by me again? You shouldn't hear any pre-emphasis curve on normal
FM. That's what de-emphasis is for.

And anyway, typical station EQ is far more radical than the emphasis curve,
I am sorry to say. The processing at typical stations is much more of a
sonic limitation than the transmission process.

IBOC AM sounds pretty awful to my ears. Much worse than good wideband AM
transmission with a good receiver (which is something hardly anyone here
will ever get a chance to hear, I am sorry to say).

While it will take time to enter the market, the sound of AM IBOC now is
very, very good. When running music on the one of these that is also in the
building, it sounds better than some local FMs.

Your local FMs must sound really dreadful.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

"Bill Blomgren" wrote in message
...
On 13 Jun 2004 22:49:37 GMT, Mark Howell wrote:

As an employee of one of several AM station owners, including CCU and
Disney, involved in a battle over interference from stations in
Northern Mexico, I beg to differ. We care a lot, and have joined in
legal action to protect our signal.

There is also some evidence that IBOC interference can affect home
metro groundwave coverage of adjacent channel stations.

Between the cubans and the mexicans,

Believe it or not, other countries also have rights to use the radio
spectrum.

Remember that WARK is off the back of WTOP's pattern. WTOP has something
like 1.5V/m @ 1 km toward WARK, not the 4+V/m like the front of their
pattern, or the 2.8V/m RMS of the pattern. The stations are about 54 miles
apart.


"Mark Howell" wrote in message
...

I certainly hope so, since they are 30 kHz apart. But there is a real
problem with first-adjacent channel interference. I reference a
statement submitted by Clear Channel SVP/Engineering Jeff Littlejohn
to the National Radio Systems Committee regarding a test involving
WTOP, Washington (1500) and WARK, Hagerstown, MD (1490). Daytime
interference from WTOP's digital signal was found to be "significant"
at WARK's protected 0.50 mV/M contour, and "noticeable" at its 0.75
mV/M contour.
The full report can be found at
http://www.am-dx.com/clearchannelrprt.pdf

Mark Howell

"R J Carpenter" wrote in message
...

"David Eduardo" wrote in message
...

There is also some evidence that IBOC interference can affect home
metro groundwave coverage of adjacent channel stations.

But not much. I can listen to the 1050 in the Riverside market within 10
miles of the 1020 KTNQ 50 kw IBOC site.

Yeah, but Riverside is in KTNQ's null - where their day pattern has the
equivalent of about 6kW, NOT 50kW. The KTNQ day pattern runs 6kW or less
over most of the ESE quadrant. They have far less toward Riverside at
night.
And Riverside is in the max of 1050's day pattern.

I was talking about listinening in Monterrey Park, right in the main lobe.

"Mark Howell" wrote in message
...
On 14 Jun 2004 04:22:21 GMT, "David Eduardo"
wrote:


But you are concened about the damage to the local signal, not the abilty
to
hear an AM hundreds of miles form its city of license.

With 5kw we're not expecting a usable signal hundreds of miles away
from the COL. But we are concerned about more than our metro coverage
area.


There is also some evidence that IBOC interference can affect home
metro groundwave coverage of adjacent channel stations.

But not much. I can listen to the 1050 in the Riverside market within 10
miles of the KTNQ 50 kw IBOC site.


I certainly hope so, since they are 30 kHz apart. But there is a real
problem with first-adjacent channel interference. I reference a
statement submitted by Clear Channel SVP/Engineering Jeff Littlejohn
to the National Radio Systems Committee regarding a test involving
WTOP, Washington (1500) and WARK, Hagerstown, MD (1490). Daytime
interference from WTOP's digital signal was found to be "significant"
at WARK's protected 0.50 mV/M contour, and "noticeable" at its 0.75
mV/M contour.

Yet today, with noise and all, anything beyond the 5 mv/m contour is pretty
useless.

"Scott Dorsey" wrote in message
...
David Eduardo wrote:
"Scott Dorsey" wrote in message
...

IBOC FM is a mixed bag. It doesn't sound all that wonderful, but again
I think most of the FM sound quality issues have to do with
overprocessing
more than anything else, and digital transmission doesn't do anything
about
that.

I am "in the building" with one of these, and on the available receivers,
FM
IBOC has definite advantages, one you realize you are hearing audio
without
the preemphasis curve we are used to hearing on FM. That done, it sounds
better to everyone who has heard real-world music programming on it.

Run that by me again? You shouldn't hear any pre-emphasis curve on normal
FM. That's what de-emphasis is for.

You hear the artifacts of it having been done, processed, and deemphasized.

While it will take time to enter the market, the sound of AM IBOC now is
very, very good. When running music on the one of these that is also in
the
building, it sounds better than some local FMs.

Your local FMs must sound really dreadful.

Los Angeles.

There is also some evidence that IBOC interference can affect home
metro groundwave coverage of adjacent channel stations.

But not much. I can listen to the 1050 in the Riverside market within 10
miles of the KTNQ 50 kw IBOC site.

I have to laugh at that (nothing personal, DE). More of this
selective "acceptable interference" while NAB Eddie and his thugs
continue their audacious lies about third adjacent LPFM.

LPFM is to Eddie what Weapons Of Mass Destruction are to George W.

Carry on.