BREAKING NEWS! THE REAL REASON WHY WGN HAS DROPPED HD-AM

[Savage]

An extremely reliable source "directly involved" with Tribune's WGN tells us, on strict condition of anonymity (typical of the intrigue surrounding HD Radio):

HD-AM has been dropped because it's interfering with Arbitron PPM technology!

IOW: the self-interference inherent in HD is preventing the PPM devices from reading WGN listening in the field. IOW: HD Radio is directly blocking reportage of AM listening to Arbitron!

This confirms the suspicions of most posters here about James Carollo's "explanation" that "processing changes being evaluated" being a plausible reason for shutting the HD exciter down. Perhaps Mr. Carollo would care to chime in and confirm or deny this report.....?

Put yourself in the position of a big cash-cow major market AM General Manager. What's gonna win? Hiss-O-Matic Interference Generator, producing a questionable product consumed by an infintesimal segment of your audience, or...Arbitron, which directly influences revenues for your station? (Please keep your eyes on your own paper.)

HD Radio. Truly, this Christmas season, the gift that keeps on giving. :

 

[JohnnyElectron]

Hmmmmm, WJR went from 1st place with diaries to 6th place with PPM - and they've now turned-off HD.
Hmmm, maybe we're on to something here! (not only PPM, but the analog sounds 10x better now too!)

Maybe PPM doesn't work on the 3-letter stations! (WJR, WGN, WOR, WLS, WGY, KYW) - I'd be curious to see if these stations are showing a huge drop in audience share using PPM because of HD interference with PPM??

 

[rbrucecarter5]

There is a real unforeseen nasty with HD-AM! iBiquity better develop a fix for that one iQuickly, or it may be all over for HD-AM. I have noticed that WGN seems to be BACK - for a long time their signal in Dallas was just so-so, even with some WOR hiss underneath. Now they are peeling paint with their signal here. Not that I listen that much, but there is something about legacy Chicago 50 kW stations that keeps me scanning for them on a regular basis. It would be really interesting to see if WLS drops their HD - will they be "back", too?!

 

[Carmine5]

Well, at least Crawford won't have to worry about this little problem. Hardly anyone listens to their AM stations anyway. They can broadcast IBOC in full confidence.

C5

 

[davideduardo]

Hmmmmm, WJR went from 1st place with diaries to 6th place with PPM - and they've now turned-off HD.
Hmmm, maybe we're on to something here! (not only PPM, but the analog sounds 10x better now too!)

AM in general is off in PPM, even more than it was declining in the diary based survey.

Maybe PPM doesn't work on the 3-letter stations! (WJR, WGN, WOR, WLS, WGY, KYW) - I'd be curious to see if these stations are showing a huge drop in audience share using PPM because of HD interference with PPM??

The PPM encoding is pure audio, and it does not matter if there is an HD component to the signal.

On the other hand, KFI is significantly up in the PPM as is KGO, WABC, KYW, WLS. It's the stodgy, over 65 geezer stations that are off.

 

[landtuna]

It's the stodgy, over 65 geezer stations that are off.

THAT'S IT! I'VE had ENOUGH!!!! As soon as I can find my <dammit, what was I looking for?> I'm coming over there and <huh? ....maybe I'll remember tomorrow>.

 

[davideduardo]

An extremely reliable source "directly involved" with Tribune's WGN tells us, on strict condition of anonymity (typical of the intrigue surrounding HD Radio):

HD-AM has been dropped because it's interfering with Arbitron PPM technology!

IOW: the self-interference inherent in HD is preventing the PPM devices from reading WGN listening in the field. IOW: HD Radio is directly blocking reportage of AM listening to Arbitron!

That's bull. WGN, with HD and under PPM, had a 7.3 share in August, towards the end of the Baseball season. The season ended, and in November, they had a 4.4. Do you really think this is an HD issue or a programming one?

In August of last year, pre-PPM, they had a 6.0. And last year November had a 5.6 and December a 4.2. Maybe the rest of the station is not as good as the baseball broadcasts.... and WGN is just suffering the same fate as nearly all AM stations.

 

[KB1OKL]

I have noticed that AM stations that turn on the iBlock get weaker although most people don't believe me. WBZ used to be much stronger in my area. So did the Kidney channel on 1560 WQEQ. That used to barrel in here and the second they turned on the jammer their signal got much weaker. It's not only jamming PPM it's jamming it's own signals!

 

[syvjeff]

There's another card that hasn't been discussed on this board regarding WGN dropping HD, Randy Michaels. I've enjoyed my time of working with Randy so this is not a jab at him but a noticed pattern. Remember he is so into making sure AM gets the most miles out of itself, he would make sure that AM Stereo would be turned off at Jacor. Maybe this is part of the same philosophy of the sound of HD and how it really cuts coverage area.

I don't have an HD AM station, but have experimented with narrowing down the bandwidth of my stations and really going full NRSC and feeding your transmitter the cleanest audio is the way to go.

 

[Savage]

"That's bull!" Ahhh, yes. The musical sweet sounds of civil discourse once again grace this board.

So, if as you lecture us, "PPM encoding is pure audio" why would it "not matter whether there is an HD component?" Anyone who has studied HD-AM for thirty seconds knows that IBOC has a profound effect on audio performance. It has been noted not only in this thread but about 200 times before in 200 previous threads. The too-many-to-enumerate deleterious effects of "HD encoding" include enormously narrowed analog bandwidth, contamination of the main channel with COFDM sideband data and increased susceptibility to QRM and QRN.

The fact of the matter is, it would be more surprising if "PPM encoding" which is "audio derived" were NOT affected by HD-AM.

Taking this development and reading it with James Carollo's cryptic declaration that WGN has turned off IBOC to evaluate "processing changes" - as in, "let's see if the absence of IBOC has any effect on trends" - it would seem logical that the station's research is seeing some adverse impact and perhaps they want to rule out HD as a contributor.

Of course Mr. Carollo may take me up on my invitation to clarify the station's actions and confirm or refute this report.

 

[Savage]

I forgot: if "AM is off generally in PPM," then that contention tends to bolster the argument that HD is hurting AM radio - instead of the opposite. If indeed the audio-derived PPM encoding is being interfered with by HD, that would affect all AM stations using HD, not just WGN. Which is precisely what David "Eduardo" Gleason is reporting.

Any adverse impact of HD on PPM performance would certainly qualify as yet another "dirty little secret" of IBOC, likely being suppressed just like the adjacent-channel interference disasters, reduced average modulation and increased analog self-interference, and on and on.

None are so blind as those who will not see. Nor so deaf as those who will not hear. The willingness of Alliance AMs to continue their self-sacrifice on the altar of this preposterously unsuccessful hybrid system is an appalling example of how stupid big-radio-group management is.

 

[rbrucecarter5]

I have noticed that AM stations that turn on the iBlock get weaker although most people don't believe me. WBZ used to be much stronger in my area.

I've been saying that about WBZ for at least a couple of years. They used to be a regular fixture here in Texas in spite of the 1030 in Casper. Since they put on IBOC - nothing. Nothing at all, and I'm in Dallas which is 200 miles from being the closest you can get to Boston and still be in Texas.

Of course they don't care about listeners outside of Boston, so they don't care that their skywave is trashed. But ---- a weaker signal in Dallas also means a weaker signal within their intended market. Which means less building penetration. Of course they would care about that if they were FM because they would want a 10 dB increase to penetrate the buildings more. But wait - all they have to do as an AM station is shut down IBOC and they will penetrate buildings more ---- I get so confused by the convoluted logic used to justify this engineering disaster my head spins. Oh by the way - FM is weaker too, because of IBOC. But nobody believes that both AM and FM coverage is less with IBOC. That is contrary to iBiquity's word. Heaven forbid somebody tell the truth about coverage - that it would be much improved if they shut this stuff off!!!!

 

[audioguy]

Here is what Jim told me, and it seems to agree with what was reported here:

"The station is adjusting processing to achieve the most appropriate
sound. It is easiest to do that with IBOC off. The station has not made
a decision about when or if it will turn IBOC back on but it is highly
unlikely that AM stereo will ever be back. I know how strongly you feel
about IBOC so just enjoy the fact that it is off. I cannot say for sure
when or if it will be back.

Jim"

I had asked if they would consider turning the C-QAM back on, since it has been reported that some HD radios have the ability to decode C-QAM. I haven't verified this since there are no C-QAM stations in the Chicago area (that I know of).

Here's what I don't understand about Jim's response: If you are "adjusting processing to achieve the most appropriate sound", and you intend to operate with an IBOC exciter with its extremely limited bandwidth, wouldn't you need to make your adjustments with the box in the line? Or perhaps, the box IS still in the line, and this is a tacit admission that the hiss is so bothersome that nobody is able to make any critical audio adjustments with the digital sidebands switched on? What do you think?

I don't understand how people can't see what a disaster IBOC is. BTW, the deadline for filing your comments about "10 dB more hiss" on FM is looming in less than an hour as I write this... hope you got yours in! I can tell you that IBIQUITY did.

 

[MarkW]

Hmmmmm, WJR went from 1st place with diaries to 6th place with PPM - and they've now turned-off HD.
Hmmm, maybe we're on to something here!

WJR turned off its IBOC during the summer, before PPM measurement began in Detroit.

I thought I read Citadel decided to shut off IBOC on all of its major market stations due to interference complaints? In particular, WJR and WABC's interference to one another's signals during skywave activity was greatly increased by the "hiss-o-matic".

 

[Link]

WLS ratings are doing well in Chicago with their IBOC on(during the day).

I don't think the main transmitter run at WGN now is CQUAM ready. Its not as simple as just flipping the switch, they would likely have to run a backup xmitter. And it sounds like Randy believes (what I think is a the myth) that CQUAM degrades coverage.

However PPM could be a convenient excuse to turn off AM IBOC from some ratings struggling stations. It seems to me the new format clock they implemented at WGN would more likely cause ratings change than AM IBOC.

I read on a engineers list that PPM does not send encoding messages during silence in audio. So some processing changes needed to be made to make sure that PPM encoding was sent regularly on talk stations. WGN may be going thru this process and feel its easier to do with IBOC out of the picture. Lets hope with IBOC off WGN's ratings go up!

 

[rbrucecarter5]

I don't think the main transmitter run at WGN now is CQUAM ready. Its not as simple as just flipping the switch, they would likely have to run a backup xmitter. And it sounds like Randy believes (what I think is a the myth) that CQUAM degrades coverage.

I thought I had debunked that one years ago, when I did a test of Dallas / Ft. Worth C-Quam stations in the highway 114 rest area near Crosbyton, TX, about 290 miles from the DFW area - daytime. Bottom line was that three C-Quam signals, KMKI, KAAM, and WBAP were not only receivable on a walkman style radio (Sony SRF-A1), but were almost static free, in spite of the location being in a valley surrounded by steep cliffs. 290 miles on a walkman - in stereo - how much range do they want from C-Quam in the day???

I also tested in Lubbock, another 40 miles distant. KKOB interference on KAAM, which had been slight in Crosbyton, increased dramatically in Lubbock. Nevertheless, C-Quam decoded with no problems. Static had also increased, but a small loop antenna cleared up all of the stations to the point they sounded almost local.

I also tested KAAM in Northwest Houston, for a standards fan. In the pre-IBOC days, the signal was almost clear on a GE Superadio 3. KMKI is directional and not receivable in NW Houston, but WBAP was as strong as a local on the GE. No audible static.

There has been a dramatic decrease in coverage and signal strength, but it is not due to C-Quam. The culprit is IBOC. I did not test WBAP after they went HD from Lubbock, but their formerly great groundwave coverage is dramatically worse in Northwest Houston. A large amount of static now. I did test KMKI and KAAM in Lubbock after the HD switch, and their signal level was dramatically reduced. KAAM was no longer even listenable - KKOB being the dominant signal on 770 over Lubbock now. KMKI is no longer almost static free, it is now very weak out there. On a mono car radio that previously had them clear away from power lines out there, it is now so weak as to be almost unlistenable. The difference is dramatic. KAAM is also almost gone in NW Houston, there is a Spanish language signal that now mixes with them. A good control on reception of KMKI is KSKY - only 40 kHz up the dial. Its signal strength is completely unchanged over the years, except for a power increase several years ago. KMKI gets dramatically weaker post HD, KSKY stays the same. The culprit isn't the radio - it is IBOC.

The one thing that is receivable with a lot of power is the stupid sidebands. I test KLIF 570 sidebands in Galveston - their formerly clear mono (which is admitted degraded by semi-local KLVI) is extremely weak in Galveston post HD conversion. But the sidebands are so strong, they are clearly audible under KLVI.

These are simple tests - iBiquity could easily have done tests like this, determined the problems, and gone back to the drawing board and fixed the problems BEFORE saddling the public with such a sad excuse of a system. They did not - either they didn't do the tests, or ignored the results. But being in denial about the problems now is not going to make them go away. And don't even bother calling me a liar until you go to the locations I mentioned with a receiver of your choice and do tests that contradict my results. Reception reports from listeners used to be not only believed, but quickly followed up by station engineers who wanted to restore coverage, and QUICK! But when it comes to the sacred cow of HD, now reception reports are ignored and those making them ridiculed into silence. How dare we challenge the "savior" of AM radio!

Why should the Dallas stations care about coverage in Houston and Lubbock? They shouldn't. But weakened signals in the fringes mean weaker signals over the metroplex, and that ought to concern them greatly. A GE SR-3 in Lubbock probably equals a $5 Walmart radio in suburban Plano in terms of receivability of these signals. That ought to scare somebody into thinking about lost local listeners and ad revenue shrinking with shrinking coverage!

 

[Savage]

"WBZ used to be much stronger in my area."

I can relate direct, first person confirmation of IBOC's effect on WBZ's analog signal. For a brief period before the issue was punted by CBS into the arena of lawyers and the FCC Enforcement Bureau, WBZ actually cooperated with WYSL to determine the effects of HD skywave on local reception. In September 2007 I situated myself in a WYSL null on a roadside with a cellphone in direct contact with WBZ's CE, armed with my trusty FIM-41 and high-quality headphones plus a digital audio recorder to quantify the impact of IBOC arriving from Boston - in real time, under controlled circumstances. With my audio recorder rolling and with our FIM carefully zeroed in on WBZ, Engineering Manager Mark Manuelian cycled the WBZ HD exciter on and off.

The results were immediate and dramatic. I happened to have one headphone on one ear and the cellphone against the other when WBZ's HD came up. I couldn't help but involuntarily exclaim, "wow!" Mark demanded to know what I meant. I described for him what I heard, 350 miles west of his facility.

As HD came on-air, I would peg the decrease in apparent loudness as detected on the FIM as at least 6db. The modulated signal became noticeably less intelligible and was immediately masked by a mushy kind of what sounded like intermod distortion. In addition there was a constant high-frequency whine. Manuelian pressed me to explain what I was hearing. My response was, well, if you guys want your station to sound like this I guess that's your business. But it certainly wouldn't be my choice.

Even the bandwidth-restricted WBZ sounded at least acceptable, even if not the sparkling and clean signal it was in the pre-IBOC days. With HD on, I have to observe: the station sounded like crap. And it still does.

Now we add about the thousandth reason to the long list of reasons "why you DON'T want HD-AM installed at your station." Lousy analog audio. Reduced coverage. Increased interference to your own signal and those of others. Outrageous expense and egregious constant maintenance headaches. Tinkering to time-align analog and digital signals. No listeners or advertisers care whether you've got HD or not. And as if those weren't enough: could be killing your ratings!

 

[davideduardo]

I read on a engineers list that PPM does not send encoding messages during silence in audio. So some processing changes needed to be made to make sure that PPM encoding was sent regularly on talk stations. WGN may be going thru this process and feel its easier to do with IBOC out of the picture. Lets hope with IBOC off WGN's ratings go up!

The PPM encoder attempts to send the tag every 4.5 seconds, or about 200 times every quarter hour. It will not send during silence, but that simply reduces the number of tags a bit... in certain circumstances, it only takes three detections in a quarter hour to get credit for the quarter hour, per Arbitron's edit rule... a small fraction of the 200 potential tags.

 

[davideduardo]

The too-many-to-enumerate deleterious effects of "HD encoding" include enormously narrowed analog bandwidth,

The Arbitron encoding is at frequencies (the encoder picks the best frequency based on audio content "gaps") that are not affected by restricted bandwidths. The device is actually fairly narrow band to avoid misdetection on other frequenices.

contamination of the main channel with COFDM sideband data

This is seldom noted... never reported with our dozen HD AM stations, in fact.

and increased susceptibility to QRM and QRN.

Which might affect far, far out of market signals... but in the WGN case, there is no surrounding market that is PPM measured where WGN would lose credits due to your imaginary interference...

It's more likely that WGN figured that, with its very, very old demographics that HD had no interest or positive advantage and was not worth the effort...

 

[davideduardo]

I forgot: if "AM is off generally in PPM," then that contention tends to bolster the argument that HD is hurting AM radio - instead of the opposite. If indeed the audio-derived PPM encoding is being interfered with by HD, that would affect all AM stations using HD, not just WGN. Which is precisely what David "Eduardo" Gleason is reporting.

AM shares are off, but the good major AMs, the ones with HD, in fact, are strong or up. It's the secondaries that are even deader... the ones without HD. Look at every PPM market... you see the same thing.

Of course, the "offness" of AM tracks the same in smaller markets, using diaries and no encoded system. Some smaller markets are down to 5 or 6 AM shares out of 100. PPM is simply showing it more precisely, but the trend in non PPM markets by non HD stations as a collective unit is the same.

You can't blame AM's death on the ratings system or HD.