New coverage maps at Radio-Locator

[ChocoMingo]

They do ... for paid subscribers. Those subscribers are paying the bills to keep the site online.

Give unlimited searches to non-paying site users and the site will eventually go dark because no one paid the bills.

I would say TANSTAAFL, except that Radio-Locator has managed to keep some amount of free access, which they really aren't obligated to provide.

That's what I meant. I think FCCData is good because it's like R-L, but has stations even from UK and Australia! And no need for subscription!

 

[K.M. Richards]

That's what I meant. I think FCCData is good because it's like R-L, but has stations even from UK and Australia! And no need for subscription!

FCCData is provided by an engineering consultancy firm. They don't need to make money from the site, and all they are providing is a easier-to-use interface to the FCC database.

You are comparing apples to walnuts, my friend.

 

[MarioMania]

I forgot what's the search limit on R-L

 

[anotherguyTN]

I believe it's 10 searches.

 

[gar hi]

I didn't realize at first that you could zoom out with these new maps.

If you look at the coverage of WCBS, for example, it's not even close to how far it gets out.

Many reports from here say it and other NYC 50 kw stations sound almost local on the outer banks and it's heard in Bermuda during the day too.

Now look at the map and zoom out.

http://radio-locator.com/cgi-bin/patg?id=WCBS-AM

 

[Steve Green NEPA]

On your WCBS 880 map, Gar, I'm about 1/2 inch south of that westernmost emblem for I-80. And WCBS 880 is audible, in some form, 24/7/365. That's on the DX radios I have here, of course. But it's there, readable, on the car radio, too.

Here is the map for co-tower WFAN 660.

http://radio-locator.com/cgi-bin/patg?id=WFAN-AM

The old R-L maps and the new ones show little difference. WFAN also is a 27/4/365 catch day and night.

Both WCBS and WFAN have virtually identical hassles pushing out far to Long Island, through all those pine barrens and sand and ducks and through all of those Levittown/East Meadow cement-slab foundations, hi.

* * * * * * *

If you can, Meat : Bring back some souvenir volcanic ash from Mauna Loa. Or Mauna Lisa, or whatever that thing was that exploded. See, there was a GREAT line (national network) from the late TV baseball announcer Richie Ashburn. He and Tim McCarver were doing some ballgame from Seattle, and a stringer brought in some volcanic rocks from nearby Mount St. Helens. The carton had different rocks from different levels.
'Huh,' said Whitey. 'Gee. I thought if you've seen one piece of ash, you've seen them all.'

 

[gar hi]

I see how WFAN (the old WNNNN...BC) has a slightly wider coverage due to it being a lower frequency but still too conservative.

And I remember Richie Ashburn and the other Phillies announcers such as Harry Kalas and By Saam.

My favorite player when I was growing up was Greg Luzinski. The Bull

 

[davideduardo]

I see how WFAN (the old WNNNN...BC) has a slightly wider coverage due to it being a lower frequency but still too conservative.

Keep in mind that those maps and the site were originally intended to serve the media community. Station owners, buyers, advertisers.

And not DXers with above average receivers and a tolerance for noise, fading and interference the average person does not possess.

Most of us look at those maps and realize that about 90% or better of all listening to a station is going to occur in an area that is about 20% inside the innermost contour. A few people will listen inside the second or middle contour, and essentially nobody will be listening in the area between the second and third contour.

If anything, the contours are overly optimistic. The inner curves should be labeled "maximum extent of regular listening".

 

[Schroedingers Cat]

In my experience, M-3 greatly overestimates the conductivity, and thus the distance to field strength contours, of AM stations. The F(50,50) computation used for FM is based on a truncated model, and assumes relatively flat terrain, and also overestimates the distances to field strength contours. For various reasons, most people, actually a great majority of people worldwide, live next to the water-oceans, lakes, and rivers. There is usually a relatively flat area next to the water that extends in several miles perpendicular but not always. Island areas from volcanic sources can rise up very rapidly. Those coastal and shoreline areas may be close to the predicted field strength. Once you get into the hills and mountains, signal attenuation becomes much greater, both a shadowing and a signal bending effect. If those areas are dry and sandy or rocky, the conductivity is even less.

M-3 Maps were constructed from Class I groundwave measurements and Class III DA proofs from the earliest AM DAs. Those also tended to be in coastal or shoreline areas where the conductivity approximates M-3. Many AM stations have moved out further from the coastal and shoreline areas, far from the coastal plains, and the conductivity is less there. Nondirectional Class IVs in small inland towns did not normally measure conductivity, and hence no conductivity data. The M-3 Map has not been revised since around 1960. That is probably why so many new AM DA arrays have disappointing service. Measuring the site conductivity before building a DA has become a lost art. Land cost, zoning, FCC and FAA regulations, etc. have become overwhelming considerations at the expense of technical advantage.

 

[Steve Green NEPA]

@ David E ....

You'll no doubt recall the discussion several years back about WFAN showing up in all those books ... inland, water path, etc. IIrc WFAN showed up in every single Long Island Sound book all the way past Providence and even into Cape Cod. You'd have that data available more than I, so bring on any corrections : -)
And I do remember WFAN showing up in the inland Hartford book -- ahead of local sports station WPOP! Every book !

Those diary respondees could not all have been DXers, of course. I'm just having the temerity to question your call about the signal portrayals being optimistic, let alone overly optimistic.

Am also wondering * how * Radio-Locator gauges, never mind mapping out, those megaphone-ish water paths.
It'd be interesting to see a Metro Bermuda Book from the 60's. And Bermuda Triangle conspiracy people out there may yet find a reference amid all of those signals sent by us Yanks into the Atlantic.

 

[Schroedingers Cat]

I'm not the great David E, but those ocean contours are generated from the same curves as the ones over land, except the ocean is considered to be 5000 mS/m. In reality, the measured salinity and conductivity in sounds and bays may be different (less because of the flow of fresh water into them). I think the European maps show the Baltic Sea to be 1000 mS/m, for instance.

 

[davideduardo]

@ David E ....

You'll no doubt recall the discussion several years back about WFAN showing up in all those books ... inland, water path, etc. IIrc WFAN showed up in every single Long Island Sound book all the way past Providence and even into Cape Cod. You'd have that data available more than I, so bring on any corrections : -)
And I do remember WFAN showing up in the inland Hartford book -- ahead of local sports station WPOP! Every book !

Those diary respondees could not all have been DXers, of course. I'm just having the temerity to question your call about the signal portrayals being optimistic, let alone overly optimistic.

Much of the listening to stations like WFAN outside its normal market area is at night and involves skywave coverage which is beyond the scope of the radio-locator maps.

However, where daytime listening did get reported (and that is the tiny percentage of listening that does not occur in the strongest signal areas) is was generally in population centers that are right along the coast of bodies of salt water.

Of course, the biggest change in signal usability over the last 20 to 30 years has been the huge increase of man made interference... dimmers, wall warts, computers, devices with CPUs, some LED lighting and all manner of newfangled contraptions that radiate buzzes, hisses and other noxious noises.

 

[gar hi]

Keep in mind that those maps and the site were originally intended to serve the media community. Station owners, buyers, advertisers.

And not DXers with above average receivers and a tolerance for noise, fading and interference the average person does not possess.

Most of us look at those maps and realize that about 90% or better of all listening to a station is going to occur in an area that is about 20% inside the innermost contour. A few people will listen inside the second or middle contour, and essentially nobody will be listening in the area between the second and third contour.

If anything, the contours are overly optimistic. The inner curves should be labeled "maximum extent of regular listening".

I definitely see your point about things from the perspective of a non-DXer when it comes to getting beyond what's supposed to be the 'local' areas.

Still, I think the outer reaches of the 'local' quality signal don't cover enough in some cases anyway.

A good example is the daytime reception of WABC down at the shore on Long Beach Island.

Even at the southern part of LBI in the town of Beach Haven, WABC has a local quality signal, not to mention WOR (another station with an inland transmitter) and of course WFAN and WCBS.

But this shows WABC as being in the 'distant' range at the location I referred to.

http://radio-locator.com/cgi-bin/patg?id=WABC-AM&h=D

Down at that part of the shore, so many of the New York stations sound like the locals and not the Philadelphia stations that are a lot closer.

The conductivity of the salt water is underestimated to a certain degree, IMO.

 

[charlestondxman]

Salt water really helps AM especially on the coast like this. I can get 610 WIOD easily in Charleston daytime even though the coverage maps for fringe probably miss by 50-75 miles.

820 from Largo, FL (Tampa) is also audible weak in Charleston sometimes, even though not a square inch of SC is covered on the map.

It all depends on the radio you have.

 

[davideduardo]

Down at that part of the shore, so many of the New York stations sound like the locals and not the Philadelphia stations that are a lot closer.

The conductivity of the salt water is underestimated to a certain degree, IMO.

It's likely not the conductivity of specific areas or of salt water is the issue. I suspect a more behind-the-scenes computer related matter causes the coastal and salt water path contours to be imprecise: there are likely very few data points on the coast of the US and its territories, so some amount of averaging is done to make the maps generate quickly over fairly large areas. I am suspecting that the data points may be quite separated, maybe between 100 to 200 km or more. An inspection of the shoreline coverage of some higher powered stations reveals that there are obviously specific data points or there would be no explanation for occasional zig-zags of bits of straight lines.

To the contrary, were there data points for every mile or two, rendering the maps would consume a great deal of computing power and use greater bandwidth to deliver to users. Additionally, as Mr. S's Cat has explained, the conductivity along the coastline is often very different as you go inland in increments of just a few miles. Since the FCC conductivity data is not so specific, we will find that the combination of very generalized conductivity charts and few coastal data points makes the maps look like there is no coastal landfall at all when, in fact, there may be right along the oceanfront. To see that would require millions of data points.

Like the 12+ and 6+ numbers from Nielsen, radio-locator.com is free. And for a free product, it's a very good "first look" at station coverage but I would never use those maps to evaluate a station purchase or to look for areas to develop audience in.

 

[gar hi]

Now I see what you're saying.

Thanks.

 

[MarioMania]

Even if there nothing close on the AM band within 2,000 miles from the East facing California in the Daytime

Would it matter by the Water?

 

[Schroedingers Cat]

There may be a huge decrease in signals going just a few miles inland, but if it is 2000 miles away, I really doubt that you are dealing with groundwave if you are hearing those. It is more likely that you are dealing with daytime skywave in those cases, particularly if it is during critical hours near sunrise and sunset.

 

[Steve Green NEPA]

WHLI from Long Island is another of those stations to make various books.

http://radio-locator.com/cgi-bin/patg?id=WHLI-AM&h=D

That's as much a water-path clearance and carte blanche as those saltwater surfers had along the Pipeline. I will testify (right hand raised in oath, left palm on an Arbitron book) that WHLI booms onto the beach along the hotel strip in Atlantic City. That place is off the map. WHLI used to show in the Monmouth-Ocean County book in New Jersey, plus one or two Connecticut books.

Here is R-L's old-style map
http://radio-locator.com/cgi-bin/pat?call=WHLI&service=AM&status=L&hours=D

Now look .... I'm not saying that the Radio-Locator maps have been in immutable print since Moses. But their portrayals have been accurate as far as my DXing 'career' has gone.

Plus, lol, they're entertaining.

 

[gar hi]

Even if there nothing close on the AM band within 2,000 miles from the East facing California in the Daytime

Would it matter by the Water?

I've always wondered if KFI can be heard at all in the daytime in Hawaii because I've read a report once of WQAM MIami being heard in the daytime up in Newfoundland, Canada which is around 2,000 miles.

Now that I'm here, I should take the PR-D5 down to Hilo right by the water in the daytime. But I don't have batteries for it because they cost an arm and a leg.

I doubt very much I will hear anything mid day at 2,462 miles but KFI is a low frequency that comes in as a steady powerhouse here at night.