On 9 Jun 2004 22:27:57 -0700, (Seagull) wrote:

G'day from Downunder


IBOC has been going in the US for some time now.

Is it as good as the people at iBiquity said it was?

No.

Does it sound any better than FM stereo or AM stereo?

Slightly worse than analog FM, depending on how the analog is
processed. It can be better than a badly processed analog signal.
The AM is very artifacty, significantly degrades the fidelity of the
analog signal, and creates significant adjacent channel interference
problems. For the latter reason, its use is forbidden at night.

Are receivers easy to buy?

No. AFAIK none are widely available.

How is AM stereo doing in the US?

Just about dead. Few receivers available except for some OEM car
radios, fewer and fewer stations broadcasting it.

Mark Howell

... and creates significant adjacent channel interference
problems. For the latter reason, its use is forbidden at night.

And likewise, it should be forbidden for daytime use also since important
componants of the signal are outside of the defined bandwidth. If all stations
go IBOC then the mutual interferance will severely reduce the coverage areas of
all stations, even the 50KWs.

IBOC = I.nterfering B.adly O.ff C.hannel

Bob Radil
A ?subject=NewsgroupRes ponse" E-Mail /A

"Bob Radil" wrote in message
...
... and creates significant adjacent channel interference
problems. For the latter reason, its use is forbidden at night.

And likewise, it should be forbidden for daytime use also since important
componants of the signal are outside of the defined bandwidth. If all
stations
go IBOC then the mutual interferance will severely reduce the coverage
areas of
all stations, even the 50KWs.

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.

On 12 Jun 2004 16:30:53 GMT, "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.


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.

Mark Howell

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, I can't get WLS reliably here in
Charlotte at night. I also have trouble with a lot of the locals. (I don't
know if they are flea power at night or what, but there is almost nothing on
the band (other than WBT) that seems to come in clearly at night.

sigh

I dread seeing what IBOC will do to the local scene.. will get even worse.

"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.

"Mark Howell" wrote in message
...
On 12 Jun 2004 16:30:53 GMT, "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.


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.

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.

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.

"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.

"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.

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.


I wouldn't presume that. Most ATUs and phasors are designed for the carrier
frequency. The fact that a transmitter may also transmit audio sidebands is a
secondary issue. IBOC splatter was certainly not taken into consideration in
the design of nearly, if not all, of the phasors in use today.

Bob Radil
A ?subject=NewsgroupRes ponse" E-Mail /A