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WBZ (AM) IBOC Off!

Driving through upstate NY last night, I scanned the AM dial looking for stations covering the South Carolina Republican primary (and eventually found WBT, Charlotte). The WBZ IBOC buzz was very prominent, as was IBOC buzz from three or four other stations.

I fail to understand why (a) any AM station runs IBOC, since it isn't a revenue generator; or (b) why the FCC allows it, since it amounts to intentional interference with the reception of other stations, something the FCC isn't supposed to tolerate.

Imagine, if you will, a 250-watt pirate station running on 1040 AM in, say, Cobleskill, NY. How long would the FCC tolerate that? But how would such a station differ in effect from the actual IBOC signal of WBZ on 1040? Now, if WBZ were getting significant revenue from IBOC, I could see an argument, however imperfect, that the economic benefit of IBOC outweighs the damage it does. But what economic benefit? It's hard to imagine WBZ doing significantly more business with IBOC than it would do without it. Of course, Ibiquity will want them to run IBOC; but if Ibiquity were to pay stations to run it, Ibiquity wouldn't be profitable, given that receiver sales can't be generating much revenue for them.

It boggles the mind.
 
4CX1000A said:
I fail to understand why (a) any AM station runs IBOC, since it isn't a revenue generator; or (b) why the FCC allows it, since it amounts to intentional interference with the reception of other stations, something the FCC isn't supposed to tolerate.

At the very least, limit it to daytime, like originally. 8)
 
4CX1000A said:
Driving through upstate NY last night, I scanned the AM dial looking for stations covering the South Carolina Republican primary (and eventually found WBT, Charlotte). The WBZ IBOC buzz was very prominent, as was IBOC buzz from three or four other stations.

I fail to understand why (a) any AM station runs IBOC, since it isn't a revenue generator; or (b) why the FCC allows it, since it amounts to intentional interference with the reception of other stations, something the FCC isn't supposed to tolerate.

Imagine, if you will, a 250-watt pirate station running on 1040 AM in, say, Cobleskill, NY. How long would the FCC tolerate that? But how would such a station differ in effect from the actual IBOC signal of WBZ on 1040? Now, if WBZ were getting significant revenue from IBOC, I could see an argument, however imperfect, that the economic benefit of IBOC outweighs the damage it does. But what economic benefit? It's hard to imagine WBZ doing significantly more business with IBOC than it would do without it. Of course, Ibiquity will want them to run IBOC; but if Ibiquity were to pay stations to run it, Ibiquity wouldn't be profitable, given that receiver sales can't be generating much revenue for them.

It boggles the mind.

I believe its because they hope it will save AM radio that anyone under 30 thinks is doomed anyways. It will take time but many new cars come with HD radios and more may follow. Obviously DXers hate it but they make very little money from you as well. It's a PPM world.
 
Johnster said:
I believe its because they hope it will save AM radio that anyone under 30 thinks is doomed anyways.

Under-30s don't "think" AM is doomed. They don't know it exists. The overwhelming majority of the under-55 audience listens to FM exclusively and advertisers eschew the over-55s like the plague.

If iBiquity really thinks HD will "save" AM, they're more clueless than I thought.
 
I fail to understand ... why the FCC allows it, since it amounts to intentional interference with the reception of other stations, something the FCC isn't supposed to tolerate.

The same argument could be made for Docket 80-90, or for LPFM. Interference is in the eye of the beholder.

Anyways, as many forum-goers know, I am a proponent of IBOC. I sat in on some of the NRSC-5 meetings. I even helped illustrate "The IBOC Handbook." But I am far from blind to its faults. Especially on AM. And speaking purely speculatively, I don't think I'm alone. I seriously doubt that there's many people who own a station or work at the FCC (or even working at iBiquity) that really think AM IBOC is going to "save" AM Radio. The problems facing AM radio are far greater than any digital broadcasting solution could hope to counteract.

So why keep it going?

Well, cynical as it sounds, I think a lot of it is sunk costs at this point. For better or worse, IBOC *is* the digital path for AM/FM broadcasting. NOTHING is going to change that. AM/FM may cease to be viable business entities, but they'll never get the necessary new spectrum for a different digital migration path. With that in mind, if you've already dropped the cash for IBOC, you might as well run it. In many cases, you've got a contract that says you must run it for X years...signed to get a discount when you first bought the gear.

But even without that contract, for the majority of AM stations that are still running IBOC, there *is* the tiny upside of making that small audience with HD receivers happy, and there's no downside: the extra electricity costs are negligible compared to the marketing benefits (also negligible, but enough to counteract it) and there's no concerns about interference to yourself. Interference concerns are for other stations that either don't impact you or belong to a competitor. Many of the cases where interference WAS a concern for a station also owned by your corporate owner are cases where IBOC was switched off, or the interference was deemed minimal enough during the revenue-making dayparts.

And hey, one never knows. Things could turn around. The FCC could change their minds and mandate receiver compliance. Who knows?

(shrugs)

I don't pretend to have any special insight into why AM IBOC stations run AM IBOC today. I can only make guesses. And not terribly-educated guesses at that. But the answer is undoubtedly linked to a simple concept: when you add up *all* the positives and negatives involved with running AM IBOC, the equation is either positive, or at least neutral. If it were negative, then they'd shut IBOC off.
 
Aaron Read wrote: "But the answer is undoubtedly linked to a simple concept: when you add up *all* the positives and negatives involved with running AM IBOC, the equation is either positive, or at least neutral. If it were negative, then they'd shut IBOC off."

But there IS a negative (maybe several) for AMs that run IBOC: 1. They are perceived by at least a few listeners as causing interference to other stations--and the interference is both real and loud. 2. The audio quality of the analog signal is degraded by the 4750-Hz analog-audio-bandwidth limitation that IBOC imposes. 3. The range of the AM-band IBOC digital signal is considerably less than that of the analog broadcasts from the same station. 4. The tiny coverage and the resulting difficulties in receiving the digital signal leave listeners with the (correct) impression that digital audio broadcasting on the AM band doesn't work.

Since hardly anyone listens to AM-band IBOC. I can see no upside to running it. If AM stations suddenly become interested in stereo, they can use the (truly compatible) C-QUAM system. AM-band IBOC is giving digital audio broadcasting a bad name! And don't AM stations that run IBOC have to pay a license fee to iBiquity? Kinda like the executioner telling the about-to-be-executed prisoner that he must pay a fee to be Guillotined;>( Even without the license fee, the cost of the added equipment to transmit the digital signal is not negligible and would prove prohibitive for many (probably most) struggling AMs.

The only way around these problems that I can see would be to eliminate the AM analog signal and transmit the digital signal at full power. Even this approach would raise some questions that, AFAIK: have not been answered. For example, the AM-band digital signal is narrower in bandwidth than the FM-band digital signal. Once the reception problems were minimized by transmitting the AM-band digital signal at full power, would listeners find the audio quality acceptable (for both speech and music)? Moreover, eliminating the analog signal would cause even bigger problems--MUCH bigger problems. I suppose that, instead of a forced transition from analog to digital, AM stations could be required to choose whether they would transmit a digital signal or an analog signal (today's "hybrid" mode would not be allowed). But there would be a strong incentive for stations to choose the analog mode because choosing the digital mode would leave a station with hardly any audience capable of receiving its broadcasts. Thus the broadcaster's investment in the license and facilities would suddenly become worthless.
 
Random thoughts: "small number of AM IBOC receivers??" Try: NONEXISTENT. AFAIK you can't even buy a receiver capable of AM HD any more unless it comes wrapped in 3500 lbs. of packaging known as a "motor vehicle" (and even then, typically as part of a multithousand-dollar nav-com-entertainment bundle.) The number of actual functioning HD-AM receivers in the hands of consumers has to be preposterously tiny.

And if "it's a PPM world," all AM IBOC should be shut off immediately, because the COFDM hash interferes with reliable encoding.

Full-digital IBOC isn't an answer either. The system would still die every time with each burst of impulse noise or lightning crackle.

Nope, folks - this is a face-saver. Nobody wants to walk into the boardroom or manager's office and say, we should shut off this turkey we've blown millions on. Deleterious to the ol' career.
(OTOH, the observation that the AM IBOC fiasco is reflecting badly on digital radio broadcasting, is certainly a valid one. Observers of our industry - like savvy ad agencies - think we're nuts to pursue an obviously failed concept.)
 
aaron, I forgot: "there's no concerns (with AM-HD) about interfering with yourself??"

Check that.

Try listening to an AM IBOC station on any quality receiver - such as a PAL/Tivoli or even a 1950s "All-American-Five" radio (any of which beat most low-priced AM-capable radios today in performance.) It's like listening to a 78 rpm record from 50 years ago with its familiar surface noise generated by the abrasive filler in the shellac, or a noisy 16mm film with optical soundtrack. Unless the radio is atypically narrowband there's a constant noise present because the radio is mixing some of the adjacent-channel digital hash with the desired audio.

That's certainly "self-interference" but mixed with the 4.7 kHz analog bandpass, it makes any IBOC originating AM station sound distinctly inferior, especially compared with a full 10 kHz well-processed all-analog station. Fatiguing.

And very, very stupid.
 
    • 1. They are perceived by at least a few listeners as causing interference to other stations--and the interference is both real and loud.
    • 2. The audio quality of the analog signal is degraded by the 4750-Hz analog-audio-bandwidth limitation that IBOC imposes.
    • 3. The range of the AM-band IBOC digital signal is considerably less than that of the analog broadcasts from the same station.
    • 4. The tiny coverage and the resulting difficulties in receiving the digital signal leave listeners with the (correct) impression that digital audio broadcasting on the AM band doesn't work.
    • 1. With the exception of a tiny handful of very savvy radio experts...most of whom are on this list...that's not the case. In the sense that, nobody who hears the interference recognizes it as IBOC-generated interference. Furthermore, the interference is to stations that are either A: owned by competitors (and thus, who cares about them) or B: distant enough that it's a completely different listenership than for the station causing the interference, and therefore that listenership is irrelevant. (unless, of course, it's to a station owned by the same corporate ownership, in which case a more nuanced analysis is needed)
    • 2. That narrowing of bandwidth was common long before IBOC came around. Many stations without IBOC voluntarily narrow because it helps reduce perceived interference. And at this point, a depressing amount of receivers can't handle any bandwidth beyond 5kHz or so anyways.
    • 3. True, but questionably relevant. Most of the AM IBOC transmitters are the "big boys" that cover huge areas. That means there's a lot of fringe where IBOC coverage is spotty, but it also means the bulk of their audience is likely covered with a strong enough signal that IBOC coverage is sufficient.
    • 4. This IS admittedly a real problem. The way analog coverage works and the way digital coverage works are two very different paradigms and virtually no listener education has been done to get them used to the difference. As a result, when a digital signal drops out to nothing (especially on FM IBOC multicast channels) the perception is that something is "wrong" or even "broken" with the station and/or the radio.


    Try listening to an AM IBOC station on any quality receiver

    You scoff at people owning HD-equipped receivers, and in the next breath suggest that there's all these "quality" AM receivers out there that people are listening to??? Hardly. The vast bulk of receivers for AM are neither HD nor able to tune much beyond 5.5 or 6kHz bandwidth, tops. Many can't even do that much. One can certainly say that is a problem, and I would agree. The voluntary degradation of AM fidelity has undoubtedly (in my book) led to "listener fatigue" of the entire AM band, and it's likely why many stations are abandoning AM for FM signals as the entire medium goes into a death spiral. But lets keep it on an apples to apples basis; self-interference just isn't that prevalent an issue. Long-distance interference? Yes, that's a problem. But not self-interference.
 
Aaron is a nice guy--and technically competent, but it's time to write him off as hopeless. AM's biggest problem for the last 50 years or so has been the virtual unavailability of decent receivers. Wasn't it Gresham's law that said "the bad money drives the good money out of circulation?" Well, the bad (read cheap) AM receivers drove the good AM receivers out of the marketplace back in the early '50s when the All-American Five died. Now we've got IBOC whackos (of whom Aaron is one) insisting that we need a needlessly complex and unworkable system (AM-band IBOC) to "save" the AM band and make it sound great (if you don't mind the continual dropouts) but requires receivers that cost a minimum of three times as much as people have demonstrated that they are willing to pay for AM radios that don't drop out three miles from the transmitter (or, in fact, at all). To succeed, a system as complicated and expensive as AM-band IBOC has got to deliver rock-solid reception and good audio quality. Proclaiming that iBiquity's monstrosity works acceptably on the AM band when it clearly does not is NOT the answer! For reasons on which I've already elaborated, doing away with AM-band IBOC's hybrid mode is unworkable, but from a purely technical standpoint, a system without a hybrid mode would be the only way to achieve digital audio transmission that could work on the AM band. The existing AM-band IBOC system--minus the hybrid mode--might be the way to do it--mainly because part of the infrastructure is already in place. But the iBiquity system is not the only digital-audio transmission system that has been demonstrated on the AM band. Unfortunately, I can't remember the name of the European digital audio transmission system that has been demoed on the MW band. However, somebody is sure to remind me.
 
Paradigm is a very sharp word. Be careful not to get cut when using it.

There is self interference, and the 50-year old hodgepodge of radios the public is using to listen
includes many where 10 khz reproduction is average.

In Chicago WLS and WGN stepped away from this pretty quickly and listener complaints were instrumental.

Chicago Cubs listeners were perhaps the most vocal and insistent.



In this paradigm everything follows curves, and straight lines are purely an illiusion.
Digital would use straight-sided waves to demand arbitrary data preservation, but still doesn't
respect the laws of curved space.

So when the traffic cop of radio pulls your AM hd signal over to the side of the road, it's because you are breaking laws
in the paradigm you are currently in, not the one you'd like to imagine yourself in.

In the imagined paradigm, digital would work , and analog wouldn't.

If something is not working, all time spent to convince the customer that it "really IS" working,
is not actually making it work for the customer, it's simply convincing them that it's hopeless
to hold their old expectations, and whatever product it is just doesn't work like it used to.

They simply lower their expectations or give up on the product.
It is too easy to see this a very expensive poison pill from other media who would love tol see terra broacast die,
especially that nasty old AM.
 
Savage said:
Random thoughts: "small number of AM IBOC receivers??" Try: NONEXISTENT. AFAIK you can't even buy a receiver capable of AM HD any more unless it comes wrapped in 3500 lbs. of packaging known as a "motor vehicle" (and even then, typically as part of a multithousand-dollar nav-com-entertainment bundle.))

The Crutchfield web site currently lists 19 models of aftermarket car radios with HD built in. None of them say anything about being FM only so I would presume they all include AM-HD.
 
iyiyi said:
What are you smoking?
Physics. And to be accurate, I study physics, not smoke it.

You do not seem to understand the dimensions and aspects of wave propogation.

Physics and dimensions. As long as we're in this paradigm, you can't get up early enough in the morning to fool them.

You can fool investors and customers, but not the laws of physics.

You can find new ways to exploit them but that's not changing the laws.

In essence, you can make the shorter 100mhz, 1 m waves bend enough to represent pulses for high speed digital modes,
but the 100 meter, 1 Mhz waves simply aren't "flexible" enough to represent such short bits or pulses without
undue "smearing" of the data, requiring excess data redudancy. At best AM iboc is heat disappation.

I'd advise a short course in some of the more recent discoveries in physics and their implications on accepted "reality".

There is still no true agreement on what waves propogate "in".
There are some old discounted ideas being dusted off, and some glaring mis-interpretations of Maxwell's equations
being questioned. Even the old discarded "ether" is being reconsidered as something apparently real.

I could go on, but I'll let you have the fun of reading up on such things.
 
Aftermarket car audio is a shrinking segment of the market. Increasingly car entertainment systems are interconnected with steering wheel remote controls, navigation and other features. Also, an increasing number of carmakers are voiding your warranty if the electronics are modified or tampered with. Even if drivers are interested in HD so much they're willing to sacrifice the factory interfaces, they don't want to lose the vehicle warranty.

It doesn't matter whether Crutchfield lists 19 HD-AM capable car radios or one hundred. What matters is, how many people are buying and/or using them?

Dan Strassberg is right. aaron is very glib at arguing the HD talking points about bandwidth of receivers, cost points, and so forth, but he's definitely drunk the iBiquity Kool-Aid. If you want to know the truth, look around you. HD-AM is broadcast on between 1 and 2% of AM stations, most of which operate IBOC daytime-only. The system does not perform acceptably in the field, which explains why the number of AM-HD stations is slowly decreasing (currently just north of 200 out of 4700 AMs in the US, down about a third from the 2008 peak.) There are no radios - at least not enough to argue about. Nobody is listening in digital and there is no prospect of any appreciable digital audience going forward.

The destructive effects have been exhaustively argued here. HD-AM is going nowhere but oblivion. Digital radio's future is with the internet, not the transmitter site, which is being tacitly
indicated by major groups' investment in other programming platforms. It's time to stop the interference which is accelerating AM's decline.
 
"Physics"? Well, if it can make 100Mhz a one meter wavelength and 1 Mhz a 100 meter wavelength; I'd sure be interested in "studying" some of that stuff! Do you know where a kid could cop a sample of this "physics"?
 
Now we've got IBOC whackos (of whom Aaron is one) insisting that we need a needlessly complex and unworkable system (AM-band IBOC) to "save" the AM band and make it sound great (if you don't mind the continual dropouts) but requires receivers that cost a minimum of three times as much as people have demonstrated that they are willing to pay for AM radios that don't drop out three miles from the transmitter (or, in fact, at all).

Dan, and Bob, I'd appreciate you not putting words in my mouth. Especially when earlier in the same page I specifically said that I'm not blind to IBOC's faults, and specifically said in relation to AM IBOC. And doubly especially to you Bob, considering that I have routinely defended your rantings about how CBS Radio and WBZ's IBOC causing interference against WYSL, even though you're right on the line of insisting they have some personal vendetta against the shining truth that must only come from WYSL.

If it'll make you happy, I think AM IBOC is a near-total train wreck.

FM IBOC I'm more sanguine on, and those of you who care to listen to what I've said know that I've long held that FM IBOC will never be a revolutionary technology the way ATSC DTV was. It's an evolutionary technology, which - by definition - is a very gradual process; much like color TV or stereo FM. The problem, of course, is that radio's viability as a medium (digital or analog) may come to an end before that evolution is even close to being finished.

But AM IBOC? Unlike FM IBOC, there are severe downsides to the technology and the upsides are even more questionable than FM's. I'm not a proponent of AM IBOC at all, except to say that as bad as it is, I don't think there's really any better solution out there. Doing nothing is, strictly-speaking, not really an option; AM broadcasting is rapidly becoming totally irrelevant for a majority of the dwindling radio listenership out there. I would not be surprised if the AM band effectively suffers a complete collapse by 2020. Maybe even sooner.

While it's a largely uninformed opinion, anecdotally I think the AM band would be best served by drastic action: eliminate all Class C and D stations, along with about 75% of the Class B's, and using the freed-up spectrum to migrate the remaining Class B's into Class A status. Possibly have a restriction preventing DA patterns for AM. Couple it with a receiver quality mandate and we'd see AM get at least some ground back on FM, as the few remaining AM stations would have better sound and MUCH less interference to deal with. Especially at night. It'd still be rearranging the deck chairs on the Titantic, but it'd be better than trying to use a shotgun and put holes in the hull to let all the water out.

Actually I think the BMC's plan to migrate every AM station to a new FM digital scheme on TV5 & 6 is utterly brilliant. I wish they'd had the clout to push that as an alternative to IBOC during the NRSC-5 meetings, although both the NAB and the FCC would almost certainly never allowed spectrum reallocation like that; any spectrum reallocation automatically goes to wireless services so they (the FCC, as mandated by Congress) can auction it for a few billion a pop.

Speaking of which, if you think I've drunk the iBiquity KoolAid, then you didn't hear what I typically had to say in private after those NRSC-5 meetings that I was "fortunate" to attend. I'm glad I went to those meetings, but it wasn't good for my blood pressure. :mad:


It doesn't matter whether Crutchfield lists 19 HD-AM capable car radios or one hundred. What matters is, how many people are buying and/or using them?

I'd say that's about 95% true. You're right that very few, if any, people are buying HD Radios and that's really what matters. The aftermarket radio scene is all but dead and buried these days; Auto OEM's are making it almost impossible to replace the stock radio with integration of the radio into the HVAC controls, steering wheel controls, GPS navigation, and other data displays. And the fragmented marketing scheme iBiquity embraced has all but guaranteed that we'll never see more than a handful of OEM car radios that come with HD Radio as an add-on, never mind as standard equipment. Companies like XMSirius were, and now Microsoft, Apple and Pandora are, undoubtedly spending a lot of money to keep it that way, too...to promote their own auditory technologies for the auto, ahead of any others.

But don't dismiss it entirely out of hand...just their mere presence does have a small but noticeable salutatory effect on receiver quality overall. To put it in perspective, if the Microsoft Zune was going to have an HD Radio receiver in it, then the iPod Nano wasn't going to have an FM receiver in it that was anything but equal or better quality. Not HD Radio, of course, but it would be at least as good an FM tuner for analog as the Zune. Granted, that's all moot just a few years later, but that's the salutatory effect I'm talking about.

Unfortunately, most of this effect went into FM. We're still not seeing AM receivers that can deliver both decent quality of reception AND decent audio fidelity. Oh well.
 
Every day this year (so far) I've been gazing at the two-tower array now being used by WSUN in Florider. It's the Fybush calendar picture for the month. Its predecessor I understand was the first directional AM array in the nation, and it has often occurred to me that directional antennas would have HELPED not HURT AM in the early days. Instead of licensing 25 lower-case 'c' clear channel stations mostly east of the Mississippi (with a couple of those west of same really close like in St. Looie MO and the Twin Cities, MN) and a high percentage of those north of the Mason-Dixon line (Rochester NY? Really?), the FCC could have authorized many more 50K outlets with somewhat gentler patterns facing the Atlantic with regard to eastern stations, and facing the Pacific for more westerly outlets. There wouldn't have been drastically directional arrays like the ones WHN-AM 1050 in NYC and KWY-AM 1060 in Philadelphia had to design. There might have been a 50K NDA or two right down the spine of the lower 48, but even so, stations could have duplicated them in Boston or even Portland, ME in the northeast or Alabama and Tampa and Miami in the southeast. Special arrangements could have been made for Canada and Mexico if they felt the need for a 50K or two with NDA's. Pre-Castro Cuber and the West Indies only needed 5K or 10K stations to meet their needs. These stations could have occupied frquencies starting at 550 right on up to about 1300. From that point upward, all stations could have been full-time with 1K like TODAY's graveyarders, but with greater separation. These would have been stations for medium and small markets. The FCC had most of the 1930's to figure this out, but instead gave the Networks and conglomerates the 25 lower-case 'c' clear channel frequencies leading to the AM dial of today.
 
Thanks, Laurence. I was hoping someone who knows more than I do about DA patterns for AM would chime in on that subject.

I vaguely suspected that DA patterns could be used constructively as you describe...allowing for more 50kW DA stations that actually functioned more cleanly than a smaller number of non-D stations would. But I have no idea how...or if...one could realistically "draw the line", as it were. Perhaps say no DA that uses more than two towers...? I don't know enough about how AM DA patterns work to really say.

One thing I *do* know is that there's a real risk of DA Class B's being mis-located after a city's sprawl has spread around them in the last 80 years...to the point where you end up with a 50kW Class B that covered all the population back in the 1950's and 60's, but is now missing a major part of the metro. WEEI (AM) in Boston is always my poster child for that concept, but there's plenty more scattered across the country. And they can't move because land is too expensive and the ratchet rule would probably make it not worth it anyways. The inevitable end of viable AM broadcasting could make this concern moot; if you could magically "fix" this "problem" everywhere, the AM band would be "dead" long before the 40-odd years pass that're needed for additional sprawl/shifting demographics to cause the problem to re-appear.
 
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