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AM HD TURNOFF PACE ACCELERATES

Meanwhile in Chicago, Disney AM 1300 has dropped the hash for a while, at least.


Not only has 1300 WRDZ turned off it's 'AM HD' garbage, but so has co-owned 50,000 watt AM 1000 WMVP.

At present I count a total of 6 AM stations in the Chicago market who have done the smart thing and turned-off their HD noise:


AM 560 WIND 5,000 watts Salem (was owned by Univision)
AM 720 WGN 50,000 watts Tribune
AM 890 WLS 50,000 watts Citadel - now broadcasting in AM Stereo!
AM 1000 WMVP 50,000 watts Disney
AM 1200 WRTO 20,000/4,500 watts Univision
AM 1300 WRDZ 4,500/4,000 watts Disney


The only ones remaining with the noise are 2 stations owned by CBS (WSCR and WBBM) and 2 stations owned by Cheap Channel (WGRB and WVON).
 
Savage said:
The WIND notation is interesting. I was under the impression Salem wasn't bothering with IBOC on any of its AMs.

They turned it off when they bought it from Univision because they had concerns that it was hurting the coverage of their 540 operation in metro Milwaukee.
 
I have 4 AM stations in my area that quit using IBOC:

630 WMAL in DC
730 WXTR in Alexandria, VA (now WTNT)
980 WTEM ESPN in DC
1500 WFED in DC, when it was WTOP
 
CC and CBS should put there AM signals on HD3 FM. AM HD does not work and only causes interference to adjucents WBZ is 50Kw and 20 miles away and can NOT get a steady lock on my Sony table radio.
One thing a will say about FM HD is that there is no L-R subcarrier noise while listening to HD program compared to analog FM. The late Peter Mitchell was right, you need a good out door antenna to receive perfectly quiet FM stereo.
 
Zach said:
L-R subcarrier noise. What does that sound like?
That's the white noise you hear when you switch a radio from mono to stereo. Most modern radios blend to mono to minimize it, but it's there on weak signals. All of the additional noise in stereo is from the L-R subcarrier.

Dave B.
 
DaveBayArea said:
Zach said:
L-R subcarrier noise. What does that sound like?
That's the white noise you hear when you switch a radio from mono to stereo. Most modern radios blend to mono to minimize it, but it's there on weak signals. All of the additional noise in stereo is from the L-R subcarrier.

Dave B.

Ah, OK gotcha. I don't think I've heard an FM stereo signal that DIDN'T have some white noise in it, even on stronger signals. With the proliferation of stereo blend in radios these days, especially car radios, I am surprised the people on here don't equate FM stereo with a failed technology. It brings two channel audio at great expense to fidelity and robustness just like HD brings a decreased noise floor and theoretically better stereo separation at the expense of adjacents, analog warmth and reliability.

In a way, I see them both as imperfect technologies yet one gets shat upon much more often than the other. The only real fly in the soup is AM HD which is a total disaster.
 
Zach, not the same at all. Analog is certainly implemented with varying results, with stations often not approaching the medium's potential. However, analog stations that don't aspire to high quality basically make a choice to let their dogs dump in their own backyards. HD stations - both AM and FM - let their dogs dump in their neighbors' backyards. BIG difference. From my perspective, a little analog L-R noise (that 99.9% of my audience doesn't even notice) is far more welcome than a bad neighbor and a yard full of turds!
 
local oscillator said:
Zach, not the same at all. Analog is certainly implemented with varying results, with stations often not approaching the medium's potential. However, analog stations that don't aspire to high quality basically make a choice to let their dogs dump in their own backyards. HD stations - both AM and FM - let their dogs dump in their neighbors' backyards. BIG difference. From my perspective, a little analog L-R noise (that 99.9% of my audience doesn't even notice) is far more welcome than a bad neighbor and a yard full of turds!

At least on FM I don't think the audience is going to notice side band interference, either. They're not listening to the side bands, they're listening to the main analog channel.

Even in crowded markets where the side bands are wiping out first adjacents from other markets, people by and large probably don't know it's HD doing it, just that their distant station isn't "coming in" anymore. Radio people (especially engineers) have to remember that the general public knows very little about their witchcraft. Few realize that dimmers, computers, switches, fluorescent lights and the like are what's ruined AM reception. They just know that the AM stations don't sound good or work very well in their suburban home. So it stands to reason they'd know even less about digital side bands.
 
Driving thru Chicago, my analog FM "SEEK" button is useless - it stopped on nearly every 1st adjacent HD station's buzz-o-matic!

On another topic, it's funny that FM stereo reduces coverage and increases noise, yet analog AM stereo doesn't increase noise and doesn't reduce coverage (unless you like to run over 125% on a regular basis). WLS-AM sounded damn fine in AM stereo on my Chrysler car radio! Stereo spots, etc...very decent.
 
Now the electronic noisemakers even affect the FM band, I've noticed.

The powers that be in radio, the makers of IBOC, the designers of ATSC, all told us that DXing wasn't important. Now we are beginning to see that all these interference sources and technologies decrease normal service area. A big aspect of DXing is an attempt to increase the normal size of the service area. So by limiting DXing, you're also reducing your normal service area. Then the answer is, well in a few years all listening and viewing will be Wi Fi internet and cell phone based, so it doesn't matter. This is what happens when when the sharks and bean counters take over where engineers used to have a much greater role.
 
Zach said:
At least on FM I don't think the audience is going to notice side band interference, either. They're not listening to the side bands, they're listening to the main analog channel.

Even in crowded markets where the side bands are wiping out first adjacents from other markets, people by and large probably don't know it's HD doing it, just that their distant station isn't "coming in" anymore. Radio people (especially engineers) have to remember that the general public knows very little about their witchcraft. Few realize that dimmers, computers, switches, fluorescent lights and the like are what's ruined AM reception. They just know that the AM stations don't sound good or work very well in their suburban home. So it stands to reason they'd know even less about digital side bands.

My concern isn't the self-interference; if stations want to do that to themselves, they can go right ahead. My concern is the interference to the adjacent channels, which in many cases exists inside the protected contours of local stations. On FM, the interference manifests itself as noise, much like the L-R variety, but often far worse. I agree that the general public is unaware of the causes of noise and interference. I also agree that on AM many of the destructive elements (computers, dimmers, fluorescent lights, etc.) come from sources we can't control (AM-HD being the notable exception), but our industry has initiated the destruction of the FM band all by itself.
 
(Tympani roll) "Ladies and gentlemen: the STIFFS....just keep on comin!"

MacLarnon reports the pop-count of AM-HDs has notched downward again - to 231. Crawford's KAAM 770 has turned off the noise (caution: this company is historically a major HD booster so this could be due to any of the 237 common reasons why the HD gets turned off unexpectedly, frequently, etc., etc.)

"Where have you gone, Tommy Ray-dee-oh? HD nation turns its lonely eyes to you..."
(Apologies to Simon & Garfunkel) :D

I've asked this before here and don't recall getting an answer, so trying again: is there such a product as an HD receiver which gets AM any more? Or are they all gone? ???
 
Savage said:
(Tympani roll) "Ladies and gentlemen: the STIFFS....just keep on comin!"

MacLarnon reports the pop-count of AM-HDs has notched downward again - to 231. Crawford's KAAM 770 has turned off the noise (caution: this company is historically a major HD booster so this could be due to any of the 237 common reasons why the HD gets turned off unexpectedly, frequently, etc., etc.)

"Where have you gone, Tommy Ray-dee-oh? HD nation turns its lonely eyes to you..."
(Apologies to Simon & Garfunkel) :D

I've asked this before here and don't recall getting an answer, so trying again: is there such a product as an HD receiver which gets AM any more? Or are they all gone? ???

They're probably all gone, but you can still buy Butter churns, hand cranked Ice Cream makers, and real motor-powered klaxon horns.
But good luck finding a wheel-and-brush typewriter eraser. :'(
Shed no tears for technology that only works in a laboratory envoronment.
 
Tom Wells said:
Shed no tears for technology that only works in a laboratory envoronment.

So, HD has something in common with the "human caused climate change."

Wow, That's an interesting connection.

Jeff in Sa-ra-so-ta!
 
Don't get me started on THAT, Jeff (the latest memo from Al Gore says we must refer to it "this week" as "climate disruption...." ::) )

I note that a year ago the AM-HD count was near 260 (albeit down from 290 in 2009.) That means an average of more than two AMs per month are turning HD off. I don't know when the last new AM-HD signal went on, but I'll bet it's been more than two years.
 
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