CBS/Infinity and IBOC-AM?

CBS/Infinity and IBOC-AM?

Post by Frank Dresse » Fri, 30 Dec 2005 14:48:19

I'm no longer hearing the IBOC sidebands as I tune past WBBM and WSCR.  Have
other CBS/Infinity stations also turned off the IBOC noise?

WIND has dropped IBOC.  Aside from the Clear Channel stations, it doesn't
seem like there's much commitment to IBOC-AM, at least in Chicago.

Frank Dresser

 
 
 

CBS/Infinity and IBOC-AM?

Post by m.. » Fri, 30 Dec 2005 17:22:15


I'll check KCBS in the AM, but it has been my experience that that IBOC
isn't always turned on.  It's not like anyone is using the service. ;-)

> I'm no longer hearing the IBOC sidebands as I tune past WBBM and WSCR.  Have
> other CBS/Infinity stations also turned off the IBOC noise?

> WIND has dropped IBOC.  Aside from the Clear Channel stations, it doesn't
> seem like there's much commitment to IBOC-AM, at least in Chicago.

> Frank Dresser

 
 
 

CBS/Infinity and IBOC-AM?

Post by Frank Dresse » Fri, 30 Dec 2005 18:18:14


Quote:> I'll check KCBS in the AM, but it has been my experience that that IBOC
> isn't always turned on.  It's not like anyone is using the service. ;-)

Yeah, that's been my expirence, so I didn't think much when I didn't hear
the noise.  IBOC started intermittently on the two CBS stations here, but
had run continously during the daytime for maybe a couple of months.  I
don't think I've heard the sidbands on either station for about 3 weeks.

Clear Channel's AM stations in Chicago continue to use IBOC.

Some, not many but some, people should be using the service.  There were a
few rather expensive IBOC receivers introduced this year.  IBOC was supposed
to be building momentum now.

It seems curious that a couple of big time clears have turned off the IBOC
sidebands during the Christmas season.

Frank Dresser

 
 
 

CBS/Infinity and IBOC-AM?

Post by R.F. Collin » Fri, 30 Dec 2005 18:43:07

It looks like WWJ here in Detroit is still running it. They also
started some ads pushing the format so I don't think it is going over
very well. All news in HD....gotta have it!

Jim

On Thu, 29 Dec 2005 05:48:19 GMT, "Frank Dresser"


>I'm no longer hearing the IBOC sidebands as I tune past WBBM and WSCR.  Have
>other CBS/Infinity stations also turned off the IBOC noise?

>WIND has dropped IBOC.  Aside from the Clear Channel stations, it doesn't
>seem like there's much commitment to IBOC-AM, at least in Chicago.

>Frank Dresser

 
 
 

CBS/Infinity and IBOC-AM?

Post by jon » Fri, 30 Dec 2005 18:42:27

Greetings Frank and all!
Pardon me for my ignorance but what is IBOC?  I will never know without
asking.  I appreciate in advance the response!  Have a great week and a
wonderful New Year!  Jon in South Carolina.
 
 
 

CBS/Infinity and IBOC-AM?

Post by RHF » Fri, 30 Dec 2005 18:56:15

For One and All,

On FM KDFC in the SF Bay Area was running IBOC
http://www.kdfc.com/new/home_flash.cfm
http://www.ibiquity.com/press/pr/061903.htm
- Owned by Bonneville International Corp.

KDFC is proud to be the first station in the world broadcasting in (HD)
digital radio, with twice the fidelity of satellite radio.
 - by  Paul Black, KDFC Engineering Department
http://www.kdfc.com/new/hd.cfm
The HD Radio signal is called an "In Band, On Channel" (IBOC) signal.

To me IBOC makes Sound Sense and Good Business Cents
for FM Stereo Radio - But for AM Talk Radio ? ? ? ? ? ? ? ?

Long, winding road ahead for digital radio
More stations are broadcasting it,
but few listeners own receivers that can get better signal
- by Benny Evangelista
- Chronicle Staff Writer
- May 31, 2004
http://sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2004/05...
NOTE - IBiquity has the upper hand in getting stations to convert
because its investors include the biggest radio corporations, including
: Clear Channel Communications, Bonneville International Corp.,
Susquehanna Radio Corp., Viacom Inc. and ABC Inc.

IBOC Radio Station "On-the-Air"
http://ibiquity.com/hdradio/hdradio_hdstations.htm

just my two cents worth ~ RHF
 .
 .
. .
       .

 
 
 

CBS/Infinity and IBOC-AM?

Post by Brenda An » Fri, 30 Dec 2005 21:16:53


Quote:> Greetings Frank and all!
> Pardon me for my ignorance but what is IBOC?  I will never know without
> asking.  I appreciate in advance the response!  Have a great week and a
> wonderful New Year!  Jon in South Carolina.

IBOC is digital (sort of) compatible radio. It stands for In Band On
Channel. The system uses a digitally modulated carrier attached to the main
carrier of an AM or FM station. In theory, it allows the two signals to
co-exist on the same frequency. In practice, it fails miserably. One of the
biggest engineering problems with IBOC on the AM band is adjacent channel
interference from the digital signal.  During the daytime, they just ignore
it (the attitude of the stations using it is that they don't care if their
digital sidebands interfere with the reception of a non-local station). It's
currently not allowed to run IBOC on AM at night due to severe interference
issues.  FM IBOC is a headache as far as trying to receive rimshot stations
on first and second adjacent channels.
 
 
 

CBS/Infinity and IBOC-AM?

Post by dxAc » Fri, 30 Dec 2005 21:20:56




> > Greetings Frank and all!
> > Pardon me for my ignorance but what is IBOC?  I will never know without
> > asking.  I appreciate in advance the response!  Have a great week and a
> > wonderful New Year!  Jon in South Carolina.

> IBOC is digital (sort of) compatible radio. It stands for In Band On
> Channel. The system uses a digitally modulated carrier attached to the main
> carrier of an AM or FM station. In theory, it allows the two signals to
> co-exist on the same frequency. In practice, it fails miserably. One of the
> biggest engineering problems with IBOC on the AM band is adjacent channel
> interference from the digital signal.  During the daytime, they just ignore
> it (the attitude of the stations using it is that they don't care if their
> digital sidebands interfere with the reception of a non-local station). It's
> currently not allowed to run IBOC on AM at night due to severe interference
> issues.  FM IBOC is a headache as far as trying to receive rimshot stations
> on first and second adjacent channels.

It's just like DRM... It's QRM!

dxAce
Michigan
USA

 
 
 

CBS/Infinity and IBOC-AM?

Post by Brenda An » Fri, 30 Dec 2005 21:42:11





>> > Greetings Frank and all!
>> > Pardon me for my ignorance but what is IBOC?  I will never know without
>> > asking.  I appreciate in advance the response!  Have a great week and a
>> > wonderful New Year!  Jon in South Carolina.

>> IBOC is digital (sort of) compatible radio. It stands for In Band On
>> Channel. The system uses a digitally modulated carrier attached to the
>> main
>> carrier of an AM or FM station. In theory, it allows the two signals to
>> co-exist on the same frequency. In practice, it fails miserably. One of
>> the
>> biggest engineering problems with IBOC on the AM band is adjacent channel
>> interference from the digital signal.  During the daytime, they just
>> ignore
>> it (the attitude of the stations using it is that they don't care if
>> their
>> digital sidebands interfere with the reception of a non-local station).
>> It's
>> currently not allowed to run IBOC on AM at night due to severe
>> interference
>> issues.  FM IBOC is a headache as far as trying to receive rimshot
>> stations
>> on first and second adjacent channels.

> It's just like DRM... It's QRM!

No arguments from me, Steve.. there goes the (DX) neighborhood.
 
 
 

CBS/Infinity and IBOC-AM?

Post by Doug Smith W9W » Fri, 30 Dec 2005 23:56:51


> Pardon me for my ignorance but what is IBOC?  I will never know without

IBOC = "In Band On Channel".  A system for transmitting digital radio
"on the same frequency" as the station's analog signal.  Also known as
"HD Radio".

In quotes, because actually adjacent frequencies are used.  For FM IBOC
the digital signal uses about half of each adjacent frequency.  (for
example, if a station on 93.1MHz uses IBOC their digital signal
stretches down to about 92.95 and up to about 93.25, using half of the
92.9 and 93.3 channels.)

For AM IBOC it uses all of the first adjacent and half of the second.
WLAC-1510's IBOC stretches down to 1495 and up to 1525.

As you might imagine, severe interference results.  On FM, the theory is
that this interference happens in areas beyond the "primary coverage" of
the station -- that *officially*, you can't get the station in places
where someone else's IBOC is interfering with it.  The FCC's definition
of a station's coverage area is far too pessimistic for good radios
(like car radios).  [0]

AM stations are currently allowed to operate IBOC only between 6am and
6pm, due to the severe interference that would be caused by running it
at night.  IBOC proponents are suggesting that the FCC stop protecting
the nighttime skywave coverage areas of clear-channel AM stations.  That
would allow stations to run their IBOC all night.  It would also mean
that millions of Americans in less-heavily-populated areas would lose
all nighttime AM service.  (if IBOC-AM were fully deployed, I would
receive *ONE* AM station at night - WSM.  100 miles west of here, the
count would be *ZERO*.  West Tennessee may not be Manhattan, but it's
not an unpopulated empty desert either...)

IBOC is unique to the United States.  The rest of the world - including
Canada - has adopted a system called "Eureka", which operates on its own
VHF/UHF frequencies and doesn't interfere with existing service.

Eureka offers every station in a city identical coverage.  I'm pretty
sure IBOC was invented mostly to prevent the adoption of Eureka in the
U.S., and the resulting ability of low-power, AM, and daytime-only
stations to develop a full-fidelity, full-time signal able to compete
with the high-powered FMs.
--
Doug Smith W9WI
Pleasant View (Nashville), TN  EM66
http://www.w9wi.com

[0] and too optimistic for cheap radios, like boom boxes & "Walkmen"...

 
 
 

CBS/Infinity and IBOC-AM?

Post by Frank Dresse » Sat, 31 Dec 2005 00:15:13


Quote:> It looks like WWJ here in Detroit is still running it. They also
> started some ads pushing the format so I don't think it is going over
> very well. All news in HD....gotta have it!

> Jim

IBOC is again on at WSCR-670.  It's still off at WBBM-780.

Both stations are talkers.  WSCR is sport talk and WBBM is all news.

Frank Dresser

 
 
 

CBS/Infinity and IBOC-AM?

Post by Frank Dresse » Sat, 31 Dec 2005 00:22:44



[snip]

Quote:

> Eureka offers every station in a city identical coverage.  I'm pretty
> sure IBOC was invented mostly to prevent the adoption of Eureka in the
> U.S., and the resulting ability of low-power, AM, and daytime-only
> stations to develop a full-fidelity, full-time signal able to compete
> with the high-powered FMs.

My pet IBOC theory is that the push for it comes from the desire to
broadcast independent channels from the sidebands.  Two or three programs
from the same license.

Quote:> --
> Doug Smith W9WI
> Pleasant View (Nashville), TN  EM66
> http://www.w9wi.com

> [0] and too optimistic for cheap radios, like boom boxes & "Walkmen"...

My old 80s era Sony Walkman is actually a decent AM dxer.  I normally will
pick up the all usual nighttime clear channel frequencies off the internal
ferrite antenna.

Frank Dresser

 
 
 

CBS/Infinity and IBOC-AM?

Post by Davi » Sat, 31 Dec 2005 00:49:27

On Thu, 29 Dec 2005 15:15:13 GMT, "Frank Dresser"




>> It looks like WWJ here in Detroit is still running it. They also
>> started some ads pushing the format so I don't think it is going over
>> very well. All news in HD....gotta have it!

>> Jim

>IBOC is again on at WSCR-670.  It's still off at WBBM-780.

>Both stations are talkers.  WSCR is sport talk and WBBM is all news.

>Frank Dresser

Don't they have to bandwidth-limit the analog when the HD's on?
 
 
 

CBS/Infinity and IBOC-AM?

Post by David Eduard » Sat, 31 Dec 2005 01:28:42




> [snip]

>> Eureka offers every station in a city identical coverage.  I'm pretty
>> sure IBOC was invented mostly to prevent the adoption of Eureka in the
>> U.S., and the resulting ability of low-power, AM, and daytime-only
>> stations to develop a full-fidelity, full-time signal able to compete
>> with the high-powered FMs.

> My pet IBOC theory is that the push for it comes from the desire to
> broadcast independent channels from the sidebands.  Two or three programs
> from the same license.

The current adaptation allows one analog and two digital signals, one of
which has the same content of the analog signal.

AM IBOC only allows one digital signal, in parallel withthe analog signal.

 
 
 

CBS/Infinity and IBOC-AM?

Post by David Eduard » Sat, 31 Dec 2005 01:35:24


> On Thu, 29 Dec 2005 15:15:13 GMT, "Frank Dresser"



>>> It looks like WWJ here in Detroit is still running it. They also
>>> started some ads pushing the format so I don't think it is going over
>>> very well. All news in HD....gotta have it!

>>> Jim

>>IBOC is again on at WSCR-670.  It's still off at WBBM-780.

>>Both stations are talkers.  WSCR is sport talk and WBBM is all news.

>>Frank Dresser

> Don't they have to bandwidth-limit the analog when the HD's on?

Only on AM. On FM the analog system suffers no degradation.