Engr. consultant: Daytime AM power should be raised 400%

[raccoonradio]

See the story (for now) on radio-info's main page and the news page

>>FCC is asked to consider raising daytime power levels by at least 400%

An engineering consultant is proposing the FCC raise AM power by 400 per cent because of
interference from powerlines, gadgets, etc. (as it says, nighttime is an entirely different matter).
I'm reminded of how in certain places, like Rt 128 nr Centennial Drive, and Rt 114 in Middelton,
WRKO is pretty much killed by power lines or something (day)...

If they can do it without affecting other stations...

>>and it’s steadily getting worse. Arsenault suggests at least a four-fold increase in power, and possibly as much as a 10-times hike for some stations. He fears that without significant relief, “AM radio service will further decline.”

 

[trojanrabbit]

Just a few points bouncing around my head.

A great opportunity was wasted to create a new band from the supposed vacating of low band VHF.

Does this mean some manufacturers (like medical devices) will have to test to higher conducted immunity standards? It might.

How many broadcasters could up their power 4x like that? And if that includes IBOC one shouldn't bother.

 

[DanStrassberg]

If they can do it without affecting other stations...

They would have to do it the way they originally did the 4X increase in daytime power for Class IV AM graveyarders (now Class Cs) back in the 1960s.

Since signal strength increases in proportion to the square root of power, all of the protected contours would have to double. Co-channel protections would become no overlap of 1.0 mV/m with interfering 0.05; first adjacent, no overlap of 1.0 with interfering 0.5; second adjacent, no overlap of 10 mV/m's; third adjacent, no overlap of 50 mV/m's. That would spell big problems in congested areas such as New England; in all likelihood, when the dust settled, only a few stations in isolated areas would be able to take advantage of the proposed rule (KSL, KDWN, KBOI et al). And notwithstanding the almost total disappearance of AM in Canada, you could expect huge protests from Canada, Mexico, and other Western Hemisphere nations--especially those in the Carribean. Ever look at the hoops US AMs in Florida have to jump through to get power increases? I think this one gets filed with the AM superpower proposal of the '60s. Thirteen of the then Class IA AMs would have been allowed 750 kW. WBZ wanted to move its transmitter to Provincetown

 

[MickeyD]

See the story (for now) on radio-info's main page and the news page

>>FCC is asked to consider raising daytime power levels by at least 400%

An engineering consultant is proposing the FCC raise AM power by 400 per cent because of
interference from powerlines, gadgets, etc. (as it says, nighttime is an entirely different matter).
I'm reminded of how in certain places, like Rt 128 nr Centennial Drive, and Rt 114 in Middelton,
WRKO is pretty much killed by power lines or something (day)...

If they can do it without affecting other stations...

>>and it’s steadily getting worse. Arsenault suggests at least a four-fold increase in power, and possibly as much as a 10-times hike for some stations. He fears that without significant relief, “AM radio service will further decline.”

I listen to AM most of the time and it really isn't the signal during the daytime that bothers me it is the nighttime signal. If you increase the power and you leave ut at four times the current operating power, noise should increase at night when the signal starts bouincing off the atmosphere.

I say do a test on some fo the graveyard frequencies and see how well it sounds. If it works well there, give it a try. I am not sure hw it would work with a 50KW station. Eurupeans would be able to pick up coastal stations much more clearly at night. They will be lie shortwave stations.

 

[WLYNWAZNgm]

I maintain that raising power all around will treat the
symptoms, not the disease. How about better
shielding of receivers, instead? Engineer-types, have at it!

 

[Lazy J]

I maintain that raising power all around will treat thesymptoms, not the disease.

The disease is AM (Antiquated Modulation) itself. Skywave Interference, Multiple Tower Arrays, Poor Audio Bandwidth... shall I continue? The only people who listen to AM radio are the people who grew up listening to AM radio. There are very few "new converts" to the AM band. Increasing the power by 400% would only cause more interference for everyone else and higher costs for stations, with very little cume increase to justify it.

Antique cars are fun to look at, but not so great as a daily driver. Sometimes we just have to move on....

(I'll go hide now! )

 

[w9wi]

I maintain that raising power all around will treat the
symptoms, not the disease. How about better
shielding of receivers, instead? Engineer-types, have at it!

Agreed that an across-the-board power increase treats the symptoms, not the disease. Better shielding of receivers, however, will accomplish little or nothing The problem is poorly shielded consumer-electronics gear that causes interference that rides in on the antenna along with the desired signals.

Enforcement of Part 15 would have left AM in much better shape. (it wouldn't cure AM's problems; many are the result of far too many AM stations & others are the result of natural static. But it would help.)

But I don't see that happening. The consumer electronics vendors would scream to high heaven, and the illegal import of uncertified gear from Asia would continue unabated. Plus all the crap that's already here, nobody's going to ship it back for something that doesn't interfere.

=============================

Dan S., doesn't the Rio treaty limit AM power to 50kw in North America?

 

[DanStrassberg]

Dan S., doesn't the Rio treaty limit AM power to 50kw in North America?

Yes, but it makes at least one exception: Mexican Class A AMs are allowed 100 kW by day. The 100 kW daytime limit MAY apply to some other countries--but NOT to the US or Canada. Also, AFAIK, the 100 kW daytime limit does not apply to Mexican Class Bs. In the US, Class Bs account for the vast majority of AMs that run 50 kW by day. The days of different rules for regional channels and clear channels are mostly gone in the US and Canada. Aside from the special protections to the skywave and secondary groundwave service areas of co-channel class As within their national borders and the special critical-hours protections afforded to the groundwave coverage of co-channel Class As within their national borders, US and Canadian Class B AMs on clear channels operate under pretty much the same rules as do US and Canadian Class B AMs on regional channels.

 

[Greg Strickland]

I suppose it is clear that the "greater good" of society favored more electrical interference to AM to facilitate (lower cost) of computers, computer networks, power distribution, lighting, etc. I think that ship has sailed.

The same DSP technology that makes the digital world possible could be used to improve the resistance of analog AM to electrical and natural interference. It is not necessary to throw the baby out with the bath water for IBOC. DSP technology could make a huge improvement to the analog system.

Electrical and natural interference occurs across the band (i.e. at adjacent channels) and is a prime candidate for noise blanking, a process that has been known for decades.

Soon your electric can opener may have an IP address, why should an AM radio be demodulating "common mode" noise? The auto industry used DSP to greatly improve the ancient internal combustion engine.

We get a DSP in the home washing machine, why not one in an AM radio to process a reduction of electrical and natural interference?

 

[radiophiler]

I'm not an engineer, so I have some questions.

When I drive through center city Philadelphia, KYW 1060 AM becomes a loud buzz on my car radio when I drive between certain high-rise buildings.

Since KYW is already 50 kw, would this proposal really help AM signals? If a 50kw AM buzzes out in its city of license, what hope is there?

Since this is on the Boston board ... does anyone there have a problem with relatively strong local AMs when they're driving in areas with tall buildings in Boston?

 

[WLYNWAZNgm]

>> Antique cars are fun to look at, but not so great as a daily driver.

Well, my 1968 Mustang Convertible is, indeed, my daily driver, for 6 months per year.
Works for me! ;D

 

[mgpt6]

Rememebr when cars pre 1965 were AM tube radios. AM didnt sound half bad back then .

 

[carmen]

We get a DSP in the home washing machine, why not one in an AM radio to process a reduction of electrical and natural interference?

most new recievers are DSP youd need at least 2 90 degree spaced loops and some intelligent phasing. at the very least.

i get AC harmonics well into HF, and the trains DC inverters add a fair amount of hash up there too.

that said AM sounds pretty awesome when you do it right, and dont use a frequency with 38 other broadcasters on it

 

[blackgold]

Hey, why don't we raise the Nighttime power instead? Let the 50 kw. blowtorches stay that way in the daytime. We can raise the night power to 1 MILLION watts! And we can close down all the AM-HD transmitters; we'll leave HD on the FM band! Also, let's add some FMExtra frequencies and extend the FM Band on both ends. Waddaya say?!

 

[Tom Wells]

>> Antique cars are fun to look at, but not so great as a daily driver.

Well, my 1968 Mustang Convertible is, indeed, my daily driver, for 6 months per year.
Works for me! ;D

Same here, except I have 3 cars that are 40 or more years old, and even drive an old car in the winter.
All have AM/FM radios by Bendix or Motorola.

I vehemently disagree that any greater good is served by junk engineeering and products, and I for one would love to hear
the consumer electronics industry squeal like a stuck pig if the FCC decided to adress wideband splatter RF products and make them behave
in compliance with pt 15 regulations. I'm not sure why the FCC hasn't simply fined their way to greatness going after the
people who are hurting radio, instead of spending so much time fining radio stations. Seems to me the FCC should be fining the local power
company for 10 months of arcing insulator at 1346 W. Oneida Ave, then distribute reparations to each station whose primary area included
that address.


I think higher power won't play well with modern radios for a number of reasons, mostly current AM design cheapness.
If interested, there is a current thread in engineering that goes into this deeper.

 

[carmen]

can raise the night power to 1 MILLION watts! Waddaya say?!

162 France runs 2 million watts. its a pretty reliable daytime catch, like 880 WCBS..

 

[WLYNWAZNgm]

I did make a couple of "modernizations" to the 'Stang:
AM/FM/CD player, and electronic ignition. At one time
we had a '71 Pinto as an extra family car (a great car, always
ran, and we put nothing into it, for 7,000 trouble-free miles)
that had an AM-only radio, with a cheesy FM converter in the glove
box. That arrangement didn't work out so well, however.

That said, I would agree that better consumer product specs would
be more advantageous than huge transmitter power increases.
Use any fines/penalties then collected, to nail pirate butt to the walls!
;D ;D ;D