AM to FM Migration Increase

[BRNout]

Good discussion!

David, my point about skywave wasn't that stations should be selling nationwide spots based on it. I agree that this is not a financially viable plan.

Rather, it was that skywave exists and shouldn't be ignored. Don't stick a bunch of locals on a frequency known to host a former clear because all you're doing is causing interference and undesirable audio that the average person won't tolerate. Putting a nighttime signal on 820 in Chicago was stupid because there already is a nighttime signal receivable on that frequency - WBAP. So (and here's my point), WCPT sounds like crap in all but it's very strongest reception zone, WBAP now sounds like crap in much of northern IL and SE WI, and the band overall suffers. This serves no one.

Accept that you're going to have skywave and plan for it. Don't stick a bunch of locals on those frequencies that are most apt to also have a 50 kw out-of-towner on them at night. Clear out the damn band and it will sound better to all concerned. I threw out the 60% figure. Perhaps an even higher figure would be necessary.

Look at the trends. There are money-making AMs around the country. What do they tend to have in common? A full-market, 50 kw blanket of a signal combined with solid local programming. By and large, you're not seeing these shoehorned locals making enough money to be truly viable in the long term. Encourage their retirement.

The FCC is actually going the wrong way on this, which is why I lay blame at their doorstep. Oh, and by the way, outlaw nighttime IBOC immediately! Not only should these transmissions not be allowed, but anyone caught with an exciter on should be fined into the Stone Age. Tuesday night, I had reception difficulty with in-market WLS being encroached on by WCBS' IBOC sidebands. Believe it or not - and it was bad. I had to null out the sidebands to hear WLS clearly. A 50 kw station serving my market. That is unacceptable. And it's a big problem for all broadcasters who are on the MW band.

 

[nocomradio]

All good points and ones I hadn't considered. Thank you for the insight.

But, and a big but.........What if some of these blowtorches were to try to do something other than standard fare talk radio, or news to a local market? Maybe at night some music programming, or something different? I wouldn't go so specific as to try to market to a tiny town in the middle of nowhere.

Its been a long time since things like the XERF 200K watter was covering most of the country, but even 1/3rd of that could have potential, I'd think at night, even with lower listener numbers. When I dial up the MW band at night here in the mid-Atlantic, I can pick up the same talk shows on sometimes as many as 8 or 9 stations up and down the Eastern Seaboard. The rest are news for Atlanta, New York, Chicago, or Charlotte. Not much else except a fading preacher lodged somewhere deep in the hash.

 

[KeithE4]

But, and a big but.........What if some of these blowtorches were to try to do something other than standard fare talk radio, or news to a local market? Maybe at night some music programming, or something different? I wouldn't go so specific as to try to market to a tiny town in the middle of nowhere.

How many of today's blowtorches absolutely need to cover a super-wide area (which should be the main qualification to get a license for any 50kW station outside of the largest cities)? KTNN 660 Window Rock AZ, which serves the Navajo Nation, is one. KRVN 880 Lexington NE serves the farming communities of Nebraska, Kansas, and points west, and is another. The big stations in Alaska would qualify. In these cases, it might be cheaper to use one huge AM transmitter rather than a network of FMs.

 

[pianoplayer88key]

But, and a big but.........What if some of these blowtorches were to try to do something other than standard fare talk radio, or news to a local market? Maybe at night some music programming, or something different? I wouldn't go so specific as to try to market to a tiny town in the middle of nowhere.

How many of today's blowtorches absolutely need to cover a super-wide area (which should be the main qualification to get a license for any 50kW station outside of the largest cities)? KTNN 660 Window Rock AZ, which serves the Navajo Nation, is one. KRVN 880 Lexington NE serves the farming communities of Nebraska, Kansas, and points west, and is another. The big stations in Alaska would qualify. In these cases, it might be cheaper to use one huge AM transmitter rather than a network of FMs.

Also there's another idea I had, although with the current band plan and interference levels I doubt it would work. You probably know there are several network feeds / stations - where the same programming is simulcast on many stations throughout the country, in many cases 24/7 (ESPN Radio, Family Radio, Radio Disney, etc).
For one thing before even considering my idea, the FCC needs to crack down on man-made static interference (preferably without imposing extra limits on intentional radiators like part 15 microbroadcasters, test equipment like signal generators, etc). For example you should be able to place your communications receiver's antenna (one as sensitive as a beverage or large ferrite sleeve loop for example) right next to a fluorescent light, computer, plasma TV, etc, and whether the "noisy" device is running or has no power at all should make absolutely no difference in the noise on a blank channel, nor should it affect a QRSS CW or PSK31 signal in any way. Once the noise problem is taken care of...

I was thinking expand the AM band down to 153 kHz, using 9 kHz spacing from 513 kHz down as that's the default tuning of most longwave-capable radios that I'm aware of. Give each nationwide simulcast network its own frequency - NOBODY else is licensed for that frequency, and the network is ONLY allowed to use that frequency for their network program (although they may possibly seek additional local licenses on other frequencies for other programs, with severe ownership limits on those). Each network builds a station using an antenna efficiency of at least 500 mV/m @ 1 km for 1 kW (maybe a sectionalized antenna, circle group antenna or combination thereof), with each section of antenna fed by a 2 or 2.5 megawatt transmitter. They would be in a rural location for safety reasons due to the high RF fields near the transmitter so they have room for adequate protection (maybe a square mile or a few) around the site, as well as to minimize the number of listeners who would have their cheap radios overloaded and deprived of signals from other adjacent stations. If necessary, they could also build co-channel transmitters on the coasts (and wherever else might be necessary) to fill in gaps in coverage. Multiple transmitters of course would be synchronized.
The channel assignments for the big stations would be spaced no closer than 18 kHz, in some cases every 27 or 36 kHz. (In "local" areas where the signal is greater than, say, 30 mV/m, spacing would be at least 72 to 90 kHz) They would all run AM Stereo with analog audio bandwidth out to at least 13.5 kHz or up to 18 kHz if possible. As for the NDBs that currently occupy a couple hundred kHz of longwave, they would be moved to frequencies "in between" the blowtorches. DGPS stations would probably stay right where they are with no broadcasters being assigned right where their frequencies are. Also on a limited basis, individual (usually smaller) stations could possibly be assigned between the big ones. As for other current uses of those frequencies, I'm not sure what to do with them, yet.

As for the rest of the AM band, I'm not totally sure yet, but something DOES need to be done (first of all getting the simulcast networks off their multiple frequencies onto individual frequencies per network, as vaguely outlined above for example). Then the band would be available for regional broadcasters (mostly in the midrange like maybe 700 to 1300 kHz or so) and local / community broadcasters (mostly in the upper portion of the band so they can use smaller antennas and still have reasonable efficiency, although I wonder if it'd be better to assign them some lower frequencies due to the high groundwave losses at higher frequencies). All stations (excepting low power operations that would produce negligible skywave fields even with a 1/4-wave or shorter antenna) would be required to use an antenna system that minimizes skywave radiation.

As for digital operation, if I was going to do that, I'd start with the network broadcasters. They would have to choose between being analog OR digital at any particular time, they couldn't use both simultaneously on the same channel (unless some technology is developed that makes it possible without mutual interference). Depending on the number of networks and available frequencies, some networks could be assigned an extra frequency so they could have analog on one channel and digital on the other, for a transition period if they so desire. (The transition period would be based in part on penetration of digital-capable receivers in the public's hands.) Even after going fully digital, stations would be allowed if desired to revert back to analog (and I think they should have analog backups in case for some reason the digital systems fail). Also, before going digital, we'd need a mode that is spectrally efficient (I've heard of modes offering up to 12 or even 16 kbits per kHz, enabling in a best case scenario a 256 kbps signal taking 16 kHz of bandwidth for example) and robust with weak signals (able to decode 100% digital even when the analog, using the same basic receiver radio circutry and antenna system, maybe only has a detectable carrier but no modulation discernible. (My preference I think would be to have DSP or similar processing in the receivers to "dig the signals out of the noise" while leaving the transmitters themselves analog, if possible.)

Ok so maybe my ideas are no better than the current implementation of IBOC, lifting of ownership caps, etc... so I'm curious as to what other options there might be?

 

[KeithE4]

Also there's another idea I had, although with the current band plan and interference levels I doubt it would work. You probably know there are several network feeds / stations - where the same programming is simulcast on many stations throughout the country, in many cases 24/7 (ESPN Radio, Family Radio, Radio Disney, etc).

No need for any of those on AM anymore. ESPN Radio is gaining affiliates on FM more and more, and Radio Disney is starting to sell off or shut down its AM stations.

For one thing before even considering my idea, the FCC needs to crack down on man-made static interference (preferably without imposing extra limits on intentional radiators like part 15 microbroadcasters, test equipment like signal generators, etc). For example you should be able to place your communications receiver's antenna (one as sensitive as a beverage or large ferrite sleeve loop for example) right next to a fluorescent light, computer, plasma TV, etc, and whether the "noisy" device is running or has no power at all should make absolutely no difference in the noise on a blank channel, nor should it affect a QRSS CW or PSK31 signal in any way. Once the noise problem is taken care of...

A physical impossibility. All electrical devices, except for maybe flashlights and incandescent bulbs, generate some kind of noise. There have been noisy devices screwing up the AM band as long as there's been an AM band.

I was thinking expand the AM band down to 153 kHz, using 9 kHz spacing from 513 kHz down as that's the default tuning of most longwave-capable radios that I'm aware of.

Several problems with this idea:
1. There has never been a longwave broadcasting service authorized in the Western Hemisphere (aka Region 2).

2. Longwave is mostly used for aircraft navigation, but hams are trying to get 500 kHz (the ARRL has a LW project with an experimental license that several hams are involved with).

3. Longwave receivers are few and far between - mostly ham rigs and general coverage receivers.

Give each nationwide simulcast network its own frequency - NOBODY else is licensed for that frequency, and the network is ONLY allowed to use that frequency for their network program (although they may possibly seek additional local licenses on other frequencies for other programs, with severe ownership limits on those). Each network builds a station using an antenna efficiency of at least 500 mV/m @ 1 km for 1 kW (maybe a sectionalized antenna, circle group antenna or combination thereof), with each section of antenna fed by a 2 or 2.5 megawatt transmitter. They would be in a rural location for safety reasons due to the high RF fields near the transmitter so they have room for adequate protection (maybe a square mile or a few) around the site, as well as to minimize the number of listeners who would have their cheap radios overloaded and deprived of signals from other adjacent stations. If necessary, they could also build co-channel transmitters on the coasts (and wherever else might be necessary) to fill in gaps in coverage. Multiple transmitters of course would be synchronized.
The channel assignments for the big stations would be spaced no closer than 18 kHz, in some cases every 27 or 36 kHz. (In "local" areas where the signal is greater than, say, 30 mV/m, spacing would be at least 72 to 90 kHz) They would all run AM Stereo with analog audio bandwidth out to at least 13.5 kHz or up to 18 kHz if possible. As for the NDBs that currently occupy a couple hundred kHz of longwave, they would be moved to frequencies "in between" the blowtorches. DGPS stations would probably stay right where they are with no broadcasters being assigned right where their frequencies are. Also on a limited basis, individual (usually smaller) stations could possibly be assigned between the big ones. As for other current uses of those frequencies, I'm not sure what to do with them, yet.

Who's gonna pay the electric bill for a 2 MW transmitter that will get very few listeners? Why use 9 kHz spacing when radios in Region 2 are configured for 10 kHz? Yes, I know there is a way to switch most radios to 9 kHz, but why bother?

As for the rest of the AM band, I'm not totally sure yet, but something DOES need to be done (first of all getting the simulcast networks off their multiple frequencies onto individual frequencies per network, as vaguely outlined above for example). Then the band would be available for regional broadcasters (mostly in the midrange like maybe 700 to 1300 kHz or so) and local / community broadcasters (mostly in the upper portion of the band so they can use smaller antennas and still have reasonable efficiency, although I wonder if it'd be better to assign them some lower frequencies due to the high groundwave losses at higher frequencies). All stations (excepting low power operations that would produce negligible skywave fields even with a 1/4-wave or shorter antenna) would be required to use an antenna system that minimizes skywave radiation.

The Department of Commerce got it right back in 1923, where the higher-powered stations (hey, some ran a whopping 500 watts! ;D ) were on 550-1050 and lower-powered ones were on 1050-1350 (the upper end of the AM band that year). Something similar should be applicable today, with 540-1220 for stations running 5-50 kW only, and 1230-1700 being "graveyard" channels - 1000 watts days, 250 watts nights max.

And eliminate directional antennas except in cases where too much signal ends up over the ocean or gets into Canada or Mexico. No more shoehorning 8-12 towers onto a lot so somebody can run 50 kW at the high end of the band (see: Detroit). Saves on maintenance costs and the excess land could be sold off. Of course, my plan would preclude high power operation at the high end anyway so that would be a moot point.

As for digital operation, if I was going to do that, I'd start with the network broadcasters. They would have to choose between being analog OR digital at any particular time, they couldn't use both simultaneously on the same channel (unless some technology is developed that makes it possible without mutual interference). Depending on the number of networks and available frequencies, some networks could be assigned an extra frequency so they could have analog on one channel and digital on the other, for a transition period if they so desire. (The transition period would be based in part on penetration of digital-capable receivers in the public's hands.) Even after going fully digital, stations would be allowed if desired to revert back to analog (and I think they should have analog backups in case for some reason the digital systems fail). Also, before going digital, we'd need a mode that is spectrally efficient (I've heard of modes offering up to 12 or even 16 kbits per kHz, enabling in a best case scenario a 256 kbps signal taking 16 kHz of bandwidth for example) and robust with weak signals (able to decode 100% digital even when the analog, using the same basic receiver radio circutry and antenna system, maybe only has a detectable carrier but no modulation discernible. (My preference I think would be to have DSP or similar processing in the receivers to "dig the signals out of the noise" while leaving the transmitters themselves analog, if possible.)

You're better off with analog AM on the AM band. Complex digital modes and the ionopshere are not exactly compatible, and I don't think FM would work any better. Any kind of phase shift makes the signal impossible to decode. I'd like to know how well those DRM transmissions work on shortwave. I've never seen a report, but I don't see it expanding either.

Ok so maybe my ideas are no better than the current implementation of IBOC, lifting of ownership caps, etc... so I'm curious as to what other options there might be?

And get rid of IBOC. Today.

 

[rfry]

... No more shoehorning 8-12 towers onto a lot so somebody can run 50 kW at the high end of the band (see: Detroit).

Some shoehorned AM broadcast stations may have 50 kW transmitters, but the h-plane ERP those stations produce at the peak of a single, major lobe can be 500 kW or more.

This reality runs counter to the original allocation concepts of the FCC, where only the ERP produced by a non-D, single MW radiator was considered when setting the transmitter power output limits and minimum antenna "efficiencies" they required for AM broadcast stations of various classes.

The subsequent FCC rules for FM broadcast stations are based on ERP and antenna HAAT (i.e., coverage potential), rather than transmitter output power and antenna gain/efficiency. Directional patterns are allowed for FM stations, but those systems cannot produce more ERP in the horizontal plane than the RMS value of the radiation pattern of a non-D FM station of the same class and HAAT.

If AM stations were bound by the FCC in these respects by the same rules as FM stations, probably there would fewer of these highly directional (Detroit style) AM stations than there are now.

RF

 

[stormy01]

Those ideas that pianoplayer88key have are great ideas, but in the US, that would work as well as the "Eureka" experiment in Canada or the similar digital band in the UK - NOT - trying to put networks on certain frequencies, or even on a "multiplex" (US broadcasters want to have separate facilities, not share facilities with - gasp! - competitors!!!) Not going to happen, sadly. There would be so much fighting for the best frequencies that it would never come to pass. And with Long Wave, we never had a chance, since LORAN was the main user of LW, and is slowly being decommissioned for GPS. But there are quite a few stations there, albeit relatively low power and a fairly large number of users who still rely on LORAN. And there's the problem of producing receivers that will tune LW. And we are all too familiar on the uptake of HD Radios, so who is to say that LW or an expanded AM/MW band will become mainstream? (It's but a dream...but a good one...) So even though LW is slowly being vacated, it won't be totally freed up for broadcast use. There are a number of government users on LW, including relatively new digital modes, so those are going to be with us for quite a while.

 

[crainbebo]

Not too long ago, CFOK 1370 in Westlock, AB switched to 97.9 FM. I used to receive that station occasionally.
Now, CKKY 830 is planning to move to 1080! I wonder how that will affect KFXX and KVNI...

Unfortunaly AM is going dead. By the time 2025 rolls around, we'll hear tons of stations playing Bollywood music, religious preaching 24/7 on 50kw stations (and KAAY is one right now) and LOTS of Spanish.

-crainbebo

 

[MarioMania]

I thought we hear Static in 2025 on AM, anywhere

 

[asugeorge1]

Oh, and by the way, outlaw nighttime IBOC immediately! Not only should these transmissions not be allowed, but anyone caught with an exciter on should be fined into the Stone Age. Tuesday night, I had reception difficulty with in-market WLS being encroached on by WCBS' IBOC sidebands. Believe it or not - and it was bad. I had to null out the sidebands to hear WLS clearly. A 50 kw station serving my market. That is unacceptable. And it's a big problem for all broadcasters who are on the MW band.

Same problem here in Phoenix with KNX 1070, a 50 kw station out of L.A., interfering with our local, KDUS 1060 (500 watts night). Pre-IBOC, the two stations used to co-exist quite nicely in the Phoenix area. KDUS has always suffered from poor night-time coverage to all points south and east, but before KNX IBOC, you could still pick-up KDUS quite clearly in those areas. But, ever since KNX went HD, KDUS is barely listenable 10 miles east or 5 miles south of their transmitter site. These areas are clearly in their coverage area, but KNX comes in so strong at night, that all you hear is IBOC hiss on 1060 with a faint sound of our local underneath. This is just one case, but it sounds like this is a growing problem all across the country.

I know a lot of HD radio apologists say that the only ones who complain about IBOC are DXer's and stations don't really care about us, but IBOC is starting to affect reception of LOCAL stations in the markets they are suppose to serve. I'm surprised more broadcasters aren't upset about this, especially when it hurts their own local coverage area. On top of that, is anyone really listening to HD radio on AM? :

 

[BRNout]

I know a lot of HD radio apologists say that the only ones who complain about IBOC are DXer's and stations don't really care about us, but IBOC is starting to affect reception of LOCAL stations in the markets they are suppose to serve. I'm surprised more broadcasters aren't upset about this, especially when it hurts their own local coverage area. On top of that, is anyone really listening to HD radio on AM? :

Exactly right! The reason why the Ibiquity/IBOC rump swabbs can get away with the "nobody complains" garbage is because 99.9% of the listeners have no clue what that jet engine sound is that's ruining reception. They don't complain about IBOC interference because they don't know what IBOC is, let alone what it's excrement sounds like. So it's really disingenuous when Bob Apple Strudel and the other HDJerks talk about how nobody cares about this issue. They do, but very few people are adequately informed about this plague on the broadcast bands. If they knew what we know, there would be thousands of complaints.

The sad reality is that many just quietly stop listening.

 

[radio-outsider]

Recently WMAL in DC moved to an FM simulcast. WTOP closed up shop on AM completely a few years back. WBBM, KCBS, WIBC, KSL, have all seen the writing on the wall. All of the few important remaining AM stations will either simulcast or abandon AM completely over the next five years.

Hey, I grew up listening to the Big 8, The Big 89, Cousin Brucie, Big Jack, et al. I built an EICO HIFI AM tuner that really sounded good! CKLW "sparkled". Bought an SRF-A100 Sony AM stereo radio, still have it, haven't used it in years. I also had a fancy turntable, DolbyB cassette deck, Betamax, Laser Disc. Hell, I even used to have a shortwave radio. All DEAD.

AM is on it's last legs as a technology, and therfore as a business. Get over it. It is even boring as a DX hobby, because there is NO CONTENT of ANY interest.

I still listen to WTOP, WINS, KGO, WBBM, etc, when I travel on business. Sometimes I even listen to them at home in NC. Under either condition, it's on my iPhone plugged into the AUX jack of the dash radio! And they sound great, no fading, and they are pretty much available anywhere anytime.

I'm starting to question whether any "linear broadcasting" as we know it makes any real long term sense.

 

[BRNout]

Recently WMAL in DC moved to an FM simulcast. WTOP closed up shop on AM completely a few years back. WBBM, KCBS, WIBC, KSL, have all seen the writing on the wall. All of the few important remaining AM stations will either simulcast or abandon AM completely over the next five years.

I don't know if I'd phrase it exactly like this. Yes, adding an FM simulcast does bring down the demos and introduce younger listeners to the format. That's my preface to this. However, it's not as simple as that......

FM is not without limitations in a sprawling, large market. For example, where i live in the Chicago area is 35-40 miles from downtown. WBBM's new FM signal (WCFS 105.9) comes in, but not perfectly. Around the house, the signal is hit or miss - especially on a portable. Sometimes, adjacent WMIL 106.1 causes the issue; other times, it's just a matter of gaps in the signal. In this area, the 105.9 signal is not the strongest Sears (yes, Sears not Woolis) Tower FM signal. Because of that, I still tune to the rock-solid and local grade WBBM 780 for news and pass up 105.9 when I am home. Heading downtown, it's a different story.

The same is true of KSL (who's FM 102.7 is one of the weaker Salt Lake signals), WSB Atlanta, and WBAP Dallas/Ft. Worth. All are simulcasting FM on signals that are vastly inferior to their AM signals in much of their respective markets. However, each of these FMs do reasonably well in areas packed with office buildings that the AM signals didn't penetrate well.

The other 2 markets you mentioned also offer good reasons for taking AM signals to FM and/or simulcasting. San Francisco/Oakland/San Jose is a geographical area filled with lots of hilly terrain. Tough place for FMs to penetrate everywhere, so AM has hung in there longer than in many places. However, we again have the office building issue - which 106.9 tends to ameliorate. But the AM still has the far better range and covers the market better.

As for Washington, that's a horrible market for AM signals - especially as it has sprawled. Washingtonians were among the first listeners in the US to dump AM for FM for that reason. Even with 50 kw, the old WTOP (at a high part of the MW band - 1500) did not serve the whole market very well. Adding the FM helped to fill in some holes - and having rimshot FMs in the exurbs hasn't hurt either. In fact, Bonneville/Hubbard needs that because the 103.5 signal doesn't reach well into fast-growing Stafford and Prince William Counties in VA nor into Frederick County, MD. So, they need THREE FMs to do the job. That market is another which has spread far and wide and which is tough to serve with only one signal. Normally, the 50 kw AM would serve that purpose. However, the ground conductivity is so bad in the region that the AM did not do this very well. Which is why it was dumped in favor of whatever else they have on there now. WMAL didn't adequately cover the market at 630, nor did it penetrate all of those office buildings where people work. Plopping them on 105.9 solved that problem as well. Again, Washington is one of the worst big markets for AM groundwave propagation and it has made a difference historically.

So, you see, it's not as simple as your blanket statement would imply. Each market has different issues to deal with. Yes, the sales demos are better on FM - no question there. However, in many (most) cases, broadcasters are still dependent on the high-powered AM to cover the whole market (which the FM may not cover in its entirety) while using the FM for sales and to serve areas where the AM is overshadowed by noise.

By simulcasting, the above-mentioned broadcasters get the best of both worlds: the fidelity and penetration of an FM signal with the excellent range of a 50 kw AM.

 

[fybush]

The same is true of KSL (who's FM 102.7 is one of the weaker Salt Lake signals), WSB Atlanta, and WBAP Dallas/Ft. Worth. All are simulcasting FM on signals that are vastly inferior to their AM signals in much of their respective markets. However, each of these FMs do reasonably well in areas packed with office buildings that the AM signals didn't penetrate well.

Though it's licensed to suburban Midvale UT, KSL-FM on 102.7 is a full C from the community tower on Farnsworth Peak, 25 kW/1140 m. It's as good as an FM signal gets in the Salt Lake market, which is very good indeed.

WSB's FM (WSBB-FM 95.5) and WBAP-FM 96.7 are indeed rimshots, but both are quite good rimshots. I wouldn't call either "vastly inferior" to their AM counterparts, especially considering that the horrendous ground conductivity in the Atlanta area makes WSB's AM signal pretty lousy in a lot of areas outside the perimeter. There are lots of places within the Atlanta market where the FM signal is significantly more usable than the AM.

WBAP and KSL do both enjoy huge AM reach outside the core parts of their home markets; you can hear KSL in most of Utah and WBAP in most of north Texas. In KSL's case, particularly, they've chosen to keep the AM simulcasting to serve the statewide audience, and given the hugely important commercial, political and religious role that Salt Lake City plays in the lives of most Utahns in the outlying areas, that's a good choice indeed.

And WBAP's situation is especially interesting: while the AM enjoys phenomenal groundwave coverage, it's not especially well located to keep up with the growth of the market. The DFW metroplex has grown almost entirely to the north, up into Collin and Wise counties and vicinity, and the AM 820 site is down south of Fort Worth. The WBAP-FM signal, which is a huge class C, is actually very well situated to serve the suburban growth up north, which is also the area most politically in tune with WBAP's talk lineup.

As for Washington, that's a horrible market for AM signals - especially as it has sprawled. Washingtonians were among the first listeners in the US to dump AM for FM for that reason. Even with 50 kw, the old WTOP (at a high part of the MW band - 1500) did not serve the whole market very well. Adding the FM helped to fill in some holes - and having rimshot FMs in the exurbs hasn't hurt either. In fact, Bonneville/Hubbard needs that because the 103.5 signal doesn't reach well into fast-growing Stafford and Prince William Counties in VA nor into Frederick County, MD. So, they need THREE FMs to do the job. That market is another which has spread far and wide and which is tough to serve with only one signal. Normally, the 50 kw AM would serve that purpose. However, the ground conductivity is so bad in the region that the AM did not do this very well. Which is why it was dumped in favor of whatever else they have on there now. WMAL didn't adequately cover the market at 630, nor did it penetrate all of those office buildings where people work. Plopping them on 105.9 solved that problem as well. Again, Washington is one of the worst big markets for AM groundwave propagation and it has made a difference historically.

WTOP's biggest problem on 1500 was the nighttime directional pattern, which has a deep null toward St. Paul - which in turn just happens to be in the direction where the richest suburban growth along the Potomac has occurred.

The groundwave propagation around DC is actually fairly decent (Atlanta, Charlotte and any Florida market you care to name are far worse); the problem in DC was outdated allocations that were designed for the small city Washington was in the 1930s, not the sprawling suburbia that exists now. And unfortunately, the solutions that have worked in other markets - moving the AMs to better locations for full-market coverage - don't work in Washington, because the sites where the AMs would have to move are either in very upscale (read: NIMBY) areas or unusable because of Dulles Airport flight paths.

So, you see, it's not as simple as your blanket statement would imply. Each market has different issues to deal with.

Indeed.

 

[davideduardo]

So, you see, it's not as simple as your blanket statement would imply. Each market has different issues to deal with. Yes, the sales demos are better on FM - no question there. However, in many (most) cases, broadcasters are still dependent on the high-powered AM to cover the whole market (which the FM may not cover in its entirety) while using the FM for sales and to serve areas where the AM is overshadowed by noise.

But let's not forget that, while coverage may be part of the issue at specific stations, the overall issue in every single market is retaining a hold on 35-54 year old listeners. This group has been eroding rather rapidly, and the average AM news talk station's average listener age has been creeping upwards by about one year every 18 months.

At some point, every such station finds that its 55+ audience is unsalable or of vastly less significance in transactions where ratings analysis is a part of the media buy.

The PPM had significant impact on this sales issue, with stations like KGO and WGN appearing around 20th in the sales demos, well off their lofty diary perches (Yes, WGN does better in baseball season... but they don't even own the team anymore).

So, what does a station in a transactional market do when they have a format that appeals to 35-54 but which is not getting much listening in that demo? If there is an FM in the cluster... any FM... simulcast. The 35-54 will listen to FM, and most, given their druthers, won't go near AM unless it is a necessity... such as exclusive sports play by play.

Look at Cox' success with limited FMs in Dayton and Jacksonville. No, they added no new coverage, but they added new sales demo listeners. It's well known that stations that score major ranker positions outside of the Metro Survey Area seldom gain any revenue from that added coverage. WBAP does not bill more because it ranks well in Waco. KFI or KLVE or KBIG don't bill any more because they are generally top 10 stations in Riverside San Bernardino. This is all about the MSA, and all about under-55 sales demos.

Sure, many AMs got a coverage fix or boost with an FM. WIBC was losing areas in the suburbs of Indianapolis at night, and FM fixed that. But they also were dropping out of the top 10 in 25-54 and that was what made the decision easier. But the real issue is that under-60 listeners have a distinct disdain for AM... the noise, the static, the quality on today's radios... and the interference by computers and CFLs and such is just a bonus.

Talk is not really an at work format. So let's not worry about office buildings; any at work listening is not going to be in office environments but more likely in vehicles and outside the white collar high rise environment. When we had data on the PPM markets prior to the conversion, we saw that the amount of at-work listening for AM talkers was in the 15% to 20% range, while music formats got over a third of their listening at work (the average is around 70% in home and at work, and 30% in car for all formats, but talk may be as much as 45% on average in the car).

So let's not worry about WBAP's signal outside the metro. Even when it has 25 or 30 mV/m in the metro, the folks advertisers want to reach won't listen because it is AM. Or, in your case, in suburban Chicago, it does not matter that a talker's AM signal is better at your location; the under 55 just ain't gonna listen to AM. Add some FM, even some bad FM signal-wise, and if the format itself is good, the sales demos tend to rise, sometimes in a spectacular manner

 

[radio-outsider]

Those markets that have FM propogation challenges have, and will copy the WTOP template with a patchwork quilt of FM signals to cover the core market if required. It certainly won't hurt to keep the AM around for "fill-in" as long as the electric bill, taxes and maintenance of the transmitter site makes economic sense for the small additional numbers it delivers. But were only talking about probably fewer than a hundred or so viable AM properties nationwide.

But one thing that has not been mentioned is that many, if not most car radio AM sections and antenna systems are so poor, that unless the field strength of an AM signal is blowtorch, it is nearly unlistenable. Auto manufacturers make no attempt to choke engine or noise generated by heater fans, windshield wipers, and other on board interferences sources. And I'm convinced my land line phone has equal if not greater fidelity. And no one complains, because frankly, no one cares. (Well, with the exception of those here

I grew up in Indianapolis, and WLS was rated in the top ten stations there well into the sixties. You can barely hear it today. It's not just the quality of the radios, but the additional background noise, and I'm convinced, deterioration of their transmitting facilities.

AM could be much better than it is, but even if it was as good as it could be, it still wouldn't be good enough to survive as a mass audience media with so many better signal propogation solutions and portable entertainment options available today.