When was the last time most consumers bought something called a "radio" that didn't have something else attached that was the main item purchased -- like a car or home theater system (what us old geezers used to call a "stereo" back in Ye Goode Olden Days)? Hint: Bill Clinton was President when it happened.
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Can "processing" bring AM radio back from the dead?
- Thread starter stewie
- Start date
When was the last time most consumers bought something called a "radio" that didn't have something else attached that was the main item purchased -- like a car or home theater system (what us old geezers used to call a "stereo" back in Ye Goode Olden Days)? Hint: Bill Clinton was President when it happened.
FM did not come "on air" in San Francisco in the 60's.
By 1947, on the new band (not where FM started in the late 30's), San Francisco had 4 FMs, San Jose, Alameda and Palo Alto each had one.
The main reason for this perception is caused by the ever-increasing noise floor on the MW and SW bands. I think it was last year, ITU adopted with the new measurement standard for a receivable MW (AM) signal (City Grade) from 5mVm to 10mVm. So really, not only is the medium dying of old age, it's being pushed into the grave by increasing terrestrial noise.
In spite of the latest discussion of the FCC finally regulating consumer product noise radiation, it seems unlikely any positive change will result in our lifetime. By that time AM will be a footnote in history books.
joebtsflk1
Star Participant
Back in the 90s, when I lived in a mortar-encrusted Faraday cage in the Twin Cities, AM reception of local stations was sub-par but still doable. No cell-phones, no CFLs (not in my house anyway), one computer.
The only thing that will cure the problem with the noise floor is...an electro-magnetic pulse. I think I'll choose to have radio below about 30 MHz (60? 100?) go away instead.
OK, I'll concede MW broadcasting of any modulation scheme is near the end as a viable medium. The remote but rather terrifying prospect of an EMP event is why we need to keep knowledge of AM technology alive. And why you should keep eating your oatmeal.
The only thing that will cure the problem with the noise floor is...an electro-magnetic pulse. I think I'll choose to have radio below about 30 MHz (60? 100?) go away instead.
OK, I'll concede MW broadcasting of any modulation scheme is near the end as a viable medium. The remote but rather terrifying prospect of an EMP event is why we need to keep knowledge of AM technology alive. And why you should keep eating your oatmeal.
Kelly, No i'm not saying MDCL will save AM radio just that it saves the AM operator a power saving$$ (50KW stations). There are radio groups that see the savings in MDCL. Closed air facilities see a reduction in how hard the AC unit need to cool the room. I have seen the savings because I asked to see before and after power bills, these were 50KW stations. I would agree that for 10kw or below the savings may be minimal.
As far as an FM translator , how can a translator cover the area of a 50KW non directional AM? Maybe 50KW at 1520, but not on the lower end of the band. There is a 50KW in Seattle running a translator and it covers a small area compared the total area served by the 50KW signal. A translator may come close to covering a 5kw or 1kw area.
As far as an FM translator , how can a translator cover the area of a 50KW non directional AM? Maybe 50KW at 1520, but not on the lower end of the band. There is a 50KW in Seattle running a translator and it covers a small area compared the total area served by the 50KW signal. A translator may come close to covering a 5kw or 1kw area.
It doesn't. You're exactly right. But a well-placed FM translator will reach enough of the population to get a sellable number. That's the idea behind "AM revitalization." Remember that even though an AM station may be able to reach 8 states, it can really only sell the metro area. So the station is reaching listeners it can't monetize. No reason for that.
stewie
Star Participant
David,
Is it true that many of the original grandfathered FM's in San Francisco have higher ERP's due to the topography of the Bay Area being "unique"?
So, what was the annual savings for a 50kW station?
In the Seattle metro, MCDL or not, I'd bet the property values on Vashon alone, (especially in the new "Amazon County") far exceed the stick value of most the AM's on the island. As AM listeners continue to sign off and the bean counters look at what it takes to keep a 50kW station running, it will be a difficult justification to keep these stations located on valuable property. Here in the DC area recently, it was determined the property value the land that WBAL-AM was on was much more worthwhile than keeping the station on it.
As far as an FM translator , how can a translator cover the area of a 50KW non directional AM? Maybe 50KW at 1520, but not on the lower end of the band. There is a 50KW in Seattle running a translator and it covers a small area compared the total area served by the 50KW signal. A translator may come close to covering a 5kw or 1kw area.[/QUOTE]
stewie
Star Participant
I've mentioned this before but it's likely we'll see a lot of these underperforming FM stations in mid-large markets flip formats and start simmulcasting their AM signal like KCBS/KFRC in San Francisco.
My 2 cents, I reserve the right to be wrong.
True, but it's due to timing and not topography. This is like Mt Wilson stations in LA, where a conforming Class B station would be, depending on the precise location, something +/- 1 kw, yet all the commercial stations are many, many times that power. Simply, they were licensed at higher equivalent power levels before the A-B-C power and height classes were established.
Add to that the continuing urban sprawl as we continue to move from a rural to an urban society, which makes the AM allotments and power levels set in the 30's totally irrelevant to today's populations. In most markets, few if any AMs put a 10 mV/m over the entire defined radio market in the daytime, and even fewer at night.
Luckily, Vashon is not totally built out. Lots of undeveloped land available with a better view and even some beach front still available. The only site that would qualify is the KVI site on the water front and I don’t even see that happening. There are no Wallmarts or Home Depot dying to build a store on Vashon. I guess since you have to take a ferry boat there that kinda limits who gets out here. Even for housing they prefer to build what residential communities Vashon has close to the town which is at the center of the Island.
Take a look at the king county website, zoom in on Vashon you can actually get info on the station land, there is better available land for building residential and commercial, if you see something you like let me know I can put you in touch with a Real Estate agent out here.
http://gismaps.kingcounty.gov/iMap/
It's a combination of all the noise-makers in the house, including several PCs and TVs, plus the fact that the stucco/lath is about a 20-30 dB RF attenuator from longwave thru UHF. In addition, there are no AM transmitters within 10 miles of my house, and most are 25-35 miles away. Most are in Phoenix, one is in Scottsdale, and two are in Apache Junction.
stewie
Star Participant
And for most everyone, the convience of a computer at every corner, phones, tablets, CFLs and LED's outweigh the interest in doing AM dx'ing or even local listening.
I'm not suggesting that all AM should be shut off, just that the benefits of AM radio have been trumped by everything else.
I have confirmed that MDCL can save a 50KW station up $1000 a month. Two of 50KW stations using MDCL (50kw day/night) in the Seattle area are enjoying saving money on their power bill. For a station that uses a closed air conditioned room the savings is about $1200 a month. The closed air conditioned station is saving on the air conditioning costs ($200). The other station is not air conditioned and saves about $1000 a month.
The saving for a 50KW day and reduced power at night may not save as much. One 50kw station that goes to 5KW night shuts off the MDCL when they are at 5KW.
The saving for a 50KW day and reduced power at night may not save as much. One 50kw station that goes to 5KW night shuts off the MDCL when they are at 5KW.
Not all radios will be fried after an EMP. It depends on the location of the radios -- those further away from the center of the US would have a higher chance of survival. Those with discrete transistors and some with IF chips will probably have a higher chance of survival than those run with microprocessors.
The problem is that no one really knows exactly which radios will survive and which ones won't, because a lot of it depends on the strength of the EMP, where it is detonated, and how high an altitude.
Chances are higher that most smart phones probably wouldn't survive if they're anywhere in line of sight of the detonation. And even if they did, the cell systems will be affected -- some possibly fried -- and those which aren't fried will have no power after a week or a month or so, when the backup generators run out of fuel -- because if the EMP is large enough, fuel production and delivery will be affected.
Of course, EMP isn't the only problem that could cause issues with broadcasting. The Cascadia Quake would make everything west of the I-5 corridor "toast", according to FEMA, and a study sponsored by several western states says that AM radio stations from east of I-5 may be the only broadcasters available to those directly affected by such a quake.
Even then -- they're just projecting. The fact is, we won't know about these things until they happen. But if/when the big one hits, if local broadcasters go down with it, regional AM stations in nearby states or nearby unaffected areas would be audible on even a cheap Sony Walkman.
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Assuming there's anyone left to run them. Keep in mind that the DHS is responsible for emergency information, not local broadcasters. The only thing local broadcasters are responsible for is making their frequencies available to designated emergency officials.
I understand.
My last paragraph was more reference to the Cascadia Quake, as opposed to EMP. If the Cascadia Quake hits, AM stations east of the Cascades, and further south in California and Nevada (and in Alberta, Canada) would probably be less affected than those along the I-5 corridor and west of it, and their signals would be audible at night (and some of them possibly during the day) in quake-affected areas on car radios and portables. And certainly those stations would carry news and other information, especially being that many AM stations like KSL, KGO, CBR, KBND, KFBK, etc are mostly news-talk stations.
I know some local and regional stations carried news and information during the blow-up of Mt St Helens.
If EMP happened, I have no idea how broadcasting would operate.
You realize that was 37 years ago? Back in those days, people still listened to AM. Not the case any more. Yes, many AM stations are "news/talk," but they mostly carry nationally syndicated programming. That was also not typically the case 37 years ago.
The following 2015 study wasn't written by AM DXers:
https://huxley.wwu.edu/files/Cascadia_Rising_high_0.pdf
A couple quotes:
"There are over a thousand telecommunications
facilities in the impacted area of Washington and
Oregon. Roughly two-thirds of these facilities may
suffer medium to high damage from the initial
earthquake ... the majority of
communications facilities in Washington’s I-5 corri-
dor may suffer medium to high damage."
"While television and FM broadcast may be available
in some areas of the I-5 corridor, their signals will be
unable to reach past the coastal mountain range to
provide service to survivors in the heavily damaged
coastal regions. With AM radio’s longer broadcast
range, survivors with power, or those who attempt
to listen in their vehicles, may be able to receive AM
radio signals." (P. 166 of the PDF)
While I agree with you that less people listen to AM radio than 37 years ago, the smartphones that everyone relies upon today to get their news and information just won't be working well for awhile in the most affected areas after the big one hits. And inland FM, AM and cable TV broadcasters may have to deal with power outages that may last longer than a week or more.
I don't think AM radio will save the day, anymore than ham radio or CB radio will save the day. But if I were in an area vulnerable to a 9.0 earthquake, I'd at least keep a Walkman in the drawer with a spare set of batteries.
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