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(USA) High Power AMs

What is 1570 XERF's current night power?
It is believed that they are running less than 50 kw now. There is no day and night power for that one, as it is on a Mexican clear channel. However, in the past they only ran from sunset to sunrise. Now it is part of the quasi-official public broadcasting organization and dedicated to local service.

The daytime coverage is not worth much... 50 kw on 1570 does not cover as much as 1 kw on 550 AM.
 
.In the later 60's, I often tried to pick up Transworld Radio from Bonaire in Quito, Ecuador... almost exactly 1000 miles away. Even using my Hammarlund HQ-180 and a loop antenna, I never could hear it in the daytime. TWR had 500 kw at 800 kHz. The distance is the same as New York City to Chicago, so one can see that those high powers might have covered a significant region, but not large portions of the whole nation.
IIRC in the late 60s TWR didn’t broadcast on 800 kHz during the bulk of daytime hours; it was mostly a late afternoon to shortly after sunrise “night/critical“ hours schedule. And if you plot the signal path from Bonaire to Quito it pretty much straddles the northern Andes, which would shred up any groundwave.

The nighttime skywave was a different matter. TWR sometimes boomed into DFW around sunset, some 2,300 miles away.

Also in the late 60s the power on 800 kHz was often listed at 525kw, not that it would make any real difference.
 
IIRC in the late 60s TWR didn’t broadcast on 800 kHz during the bulk of daytime hours; it was mostly a late afternoon to shortly after sunrise “night/critical“ hours schedule. And if you plot the signal path from Bonaire to Quito it pretty much straddles the northern Andes, which would shred up any groundwave.
There were many years it did a daytime service in Spanish for the area from Maiquetía, Venezuela to about Cartagena, Colombia and even Colón, Panamá.
The nighttime skywave was a different matter. TWR sometimes boomed into DFW around sunset, some 2,300 miles away.
It did OK in Quito, but not great. One of my stations was on 805, and it did not bother us much.
Also in the late 60s the power on 800 kHz was often listed at 525kw, not that it would make any real difference.
TWR has an odd habit of listing the maximum power of its transmitters. They still do with the new Nautel they put in recently in Bonaire.
 
There were many years it did a daytime service in Spanish for the area from Maiquetía, Venezuela to about Cartagena, Colombia and even Colón, Panamá.

It did OK in Quito, but not great. One of my stations was on 805, and it did not bother us much.

TWR has an odd habit of listing the maximum power of its transmitters. They still do with the new Nautel they put in recently in Bonaire.
That daytime service would seem to be a lot of watts to cover a pretty small area. I remember Radio Nederland leasing TWR on 800's facility for an English, Spanish and I think Dutch Caribbean service starting at 6pm.
 
That daytime service would seem to be a lot of watts to cover a pretty small area. I remember Radio Nederland leasing TWR on 800's facility for an English, Spanish and I think Dutch Caribbean service starting at 6pm.
The coverage daytime was not that bad... it ran from the coastal area East of Caracas to Eastern Panamá, a distance of nearly 1000 miles and including Caracas, Maracaibo, Santa Marta, Barranquilla, Cartagena and a bunch of other coastal cities. From what I recall, from working on some projects in Venezuela in the 70's and visiting often in the late 60s, the signal only made it 30 to 40 miles inland at best.

I don't think that the Netherlands entity leased the station... I think TWR gave the time as an exchange for the licensing and permits.

Did they actually do a Dutch service? The Netherlands Antilles speak Papaiamento, along with English and Spanish, but I never ever heard "real" Dutch spoken there, even if technically Dutch is one of the three official languages.
 
I don't think that the Netherlands entity leased the station... I think TWR gave the time as an exchange for the licensing and permits.
At the time (mid to late 60s) Radio Netherlands itself referred to the transmissions as purchased airtime. The deal included two hours on 800 kHz and seven hours on TWR's 250kw shortwave transmitter (TWR also had a 50kw shortwave unit that was not part of the deal.)

The RN block on 800 kHz ran from 2330 to 0130 UTC. Spanish was on at 2330, English at 0020, and a 20 minute news/current affairs block in Dutch aired at 0110. Three days a week the Spanish and English broadcasts were combined into a bilingual 100 minute show. The rest of the week the medium wave programming was pretty much the same as what was scheduled on shortwave.

The shortwave blocks ran from 2000 to 2320 UTC (Dutch, then English to West Africa, followed by Spanish to South America) and also 0130 to 0450 UTC (English then Dutch to North America, followed by Spanish to Central America and Mexico.)

The shortwave lease on TWR ran from 1964 until 1969, when RN opened its own shortwave facility on Bonaire. The medium wave lease ran until the late 1970s. IIRC the two hour block on 800 kHz was moved up to 2300 UTC towards the end of that arrangement.
Did they actually do a Dutch service? The Netherlands Antilles speak Papaiamento, along with English and Spanish, but I never ever heard "real" Dutch spoken there, even if technically Dutch is one of the three official languages.
Yes, the 20 minute broadcast at 0110 UTC on 800 kHz was pure Dutch, identical to the first 20 minutes of the 80 minute international shortwave version. However when RN opened its own shortwave facility on Bonaire in 1969 its SW output did have a Dutch-Papiamento hybrid broadcast (which also included Sranan Tongo) aimed at the various Dutch islands in the Caribbean as well as Suriname. This ran for many years at 2130 UTC, but much later on was moved to a morning broadcast at 0930 UTC.

Lot of languages spoken in the Dutch Antilles. A former work colleague of mine was from Aruba, and she spoke English, Spanish, Papiamento, Dutch, as well as German. She also knew sign language!
 
The 750kw would just be for nighttime theoretically, right? But even a tenfold increase of power (50 to 500) should be an improvement of distance, even if it doesn't necessarily mean it sounds better locally.
Remember it's the square root of the increase or decrease on power. Since the square root of 10 is 3.16, a 500 kw station is cranking out a little over 3 times the voltage of a 50 kw facility, so the ground wave travels 3 times farther out. This is assuming we're talking about the same frequency and the same antenna system. The S/N ratio is also improved at a given location by three times.
 
At the time (mid to late 60s) Radio Netherlands itself referred to the transmissions as purchased airtime. The deal included two hours on 800 kHz and seven hours on TWR's 250kw shortwave transmitter (TWR also had a 50kw shortwave unit that was not part of the deal.)
Well, I am seeing that my belief about the operation was pretty inaccurate.

Together with the owners of the 800 khz stations in Maracaibo, Bucaramanga, Guayaquil and Panama City, I was trying to get some kind of international action to shut TWR down as our stations were being destroyed by TWR. My station was on 805 in Quito.

Unlike the operators of HCJB, who tried very hard to work with other broadcasters, dealing with TWR was almost diabolical in its disregard for secular commercial stations.
The shortwave blocks ran from 2000 to 2320 UTC (Dutch, then English to West Africa, followed by Spanish to South America) and also 0130 to 0450 UTC (English then Dutch to North America, followed by Spanish to Central America and Mexico.)
I never figured out why 800 was selected. There was a higher power station in Maracaibo, a 10 kw in Bucaramanga, a 10 kw in Panama City as well as a 5 kw in San Jose, another 10 kw in Guatemala City and a major 150 kw station in northern Mexico.
A lot of languages spoken in the Dutch Antilles. A former work colleague of mine was from Aruba, and she spoke English, Spanish, Papiamento, Dutch, as well as German. She also knew sign language!
Both Curacao and Aruba were favorite getaways for me in the 70's and 80's, as there were cheap and convenient flights from San Juan as well as hot and cold running trade deals. I also visited a couple of times on cruise ships out of San Juan, but don't recall hearing anything other than Papiamento (or Papiamentu as some spell it), Spanish and English.

Before his passing, I even established a friendship with the owner of Radio Kelkboom, Emile Kelkboom, a 1435 AM station on Aruba. The pioneer in broadcasting there, in fact.
 
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Depends on what you consider a lot. AM listening has been in an increasing downward spiral for the past twenty years.
I was referring to OTA radio in general, AM, FM, HD, etc.. FM listening has dropped also. Eventually it all will 'spiral.' Until then, OTA has to do what it can do to stay receivable, and in the case of the AM stations, it's keep your power or go FM, and develop and promote your stream. Mainly to counter the RFI, but also because streaming is the future.
 
I was referring to OTA radio in general, AM, FM, HD, etc.. FM listening has dropped also. Eventually it all will 'spiral.' \
That prediction has been made since the 70's. Hasn't happened yet.
Until then, OTA has to do what it can do to stay receivable, and in the case of the AM stations, it's keep your power or go FM, and develop and promote your stream.
AM stations have technical and programming concrete shoes dragging them under water. First, on the technical side is inferior audio quality. Just about anything sounds better than AM. Second is terrestrial noise. Even 50kW clear channels can't be heard in urban or suburban communities like they used to. About six years ago the ITU determined that for average listening to occur using conventional consumer radio's, the listener needed to be in the 10mV/m field strength. For decades that level was 5mV/m. Word is, considering the increasing levels of interference from natural and man-made noise, the ITU is considering increasing the recommended field strength standard to 20mV/m. Frankly, I think we're already at that point.

From a programming standpoint, many AM stations have moved to syndicated programming to save costs, but used to have programming which reaches a demo. Any demo. That remaining demo is dying, literally. When it comes to streaming, they've backed themselves into a corner. The syndication organization many times won't allow individual stations to stream their network content. Reason is; as a station, unless you pay a boatload to a streaming provider to provide 'geo-fencing' of streaming to within the bounds of your market, an individual market like Poughkeepsie, can't stream to someone in Seattle. That, and streaming your station is still expensive. Unless you develop a full streaming business like iHeart, or Pandora/SXM have, and except for a handful of unique public stations, individual commercial stations doing streaming is out of the question.
Mainly to counter the RFI, but also because streaming is the future.
There is no countering terrestrial noise. Those horses left the barn years ago. The barn since burned down and there's no place for horses to return. Consumer products from overseas have taken over. It's too late to turn back the clock for the sake of saving AM stations.
 
Well, I am seeing that my belief about the operation was pretty inaccurate.

Together with the owners of the 800 khz stations in Maracaibo, Bucaramanga, Guayaquil and Panama City, I was trying to get some kind of international action to shut TWR down as our stations were being destroyed by TWR. My station was on 805 in Quito.

Unlike the operators of HCJB, who tried very hard to work with other broadcasters, dealing with TWR was almost diabolical in its disregard for secular commercial stations.

I never figured out why 800 was selected. There was a higher power station in Maracaibo, a 10 kw in Bucaramanga, a 10 kw in Panama City as well as a 5 kw in San Jose, another 10 kw in Guatemala City and a major 150 kw station in northern Mexico.

Both Curacao and Aruba were favorite getaways for me in the 70's and 80's, as there were cheap and convenient flights from San Juan as well as hot and cold running trade deals. I also visited a couple of times on cruise ships out of San Juan, but don't recall hearing anything other than Papiamento (or Papiamentu as some spell it), Spanish and English.

Before his passing, I even established a friendship with the owner of Radio Kelkboom, Emile Kelkboom, a 1435 AM station on Aruba. The pioneer in broadcasting there, in fact.
Bearing in mind this was decades ago, I read a book by I think the founder of TWR who only said that "a radio station went bankrupt and we were able to use 800". No idea what that have been.

I'm sure TWR was going to be no help to a station like CKLW playing "devil rock and roll".
 
At the time (mid to late 60s) Radio Netherlands itself referred to the transmissions as purchased airtime. The deal included two hours on 800 kHz and seven hours on TWR's 250kw shortwave transmitter (TWR also had a 50kw shortwave unit that was not part of the deal.)

The RN block on 800 kHz ran from 2330 to 0130 UTC. Spanish was on at 2330, English at 0020, and a 20 minute news/current affairs block in Dutch aired at 0110. Three days a week the Spanish and English broadcasts were combined into a bilingual 100 minute show. The rest of the week the medium wave programming was pretty much the same as what was scheduled on shortwave.

The shortwave blocks ran from 2000 to 2320 UTC (Dutch, then English to West Africa, followed by Spanish to South America) and also 0130 to 0450 UTC (English then Dutch to North America, followed by Spanish to Central America and Mexico.)

The shortwave lease on TWR ran from 1964 until 1969, when RN opened its own shortwave facility on Bonaire. The medium wave lease ran until the late 1970s. IIRC the two hour block on 800 kHz was moved up to 2300 UTC towards the end of that arrangement.

Yes, the 20 minute broadcast at 0110 UTC on 800 kHz was pure Dutch, identical to the first 20 minutes of the 80 minute international shortwave version. However when RN opened its own shortwave facility on Bonaire in 1969 its SW output did have a Dutch-Papiamento hybrid broadcast (which also included Sranan Tongo) aimed at the various Dutch islands in the Caribbean as well as Suriname. This ran for many years at 2130 UTC, but much later on was moved to a morning broadcast at 0930 UTC.

Lot of languages spoken in the Dutch Antilles. A former work colleague of mine was from Aruba, and she spoke English, Spanish, Papiamento, Dutch, as well as German. She also knew sign language!
This was later in the 70s, but my foggy brain seems to remember the RN broadcasts being cut to 70 minutes. I remember Tom Meijer doing a separate bilungual "Happy Station 70 (referring to the length)" where he spoke i a mellow tone, I guess getting his Carribean vibe on.
 
Unlikely in the near term. The relatively few healthy AM broadcasters are almost all Class A licenses, so they have even less incentive than the class B, C, and D stations to consider alternative technical solutions.

The exceptions might be Class A AMs with a 24/7 simulcast on FM, like WSB, WBBM and KYW.
 
Bearing in mind this was decades ago, I read a book by I think the founder of TWR who only said that "a radio station went bankrupt and we were able to use 800". No idea what that have been.
Yeah, that sounds like their attitude. Besides owning stations in Ecuador back in the later 60's, I compiled and edited several editions of the Latin American AM log for the National Radio Club, and there was no station on 800 that went bankrupt. Not in the Netherlands Antilles, not in Venezuela, Colombia, Panamá, Ecuador, Central America or anywhere in the Caribbean.
I'm sure TWR was going to be no help to a station like CKLW playing "devil rock and roll".
Or a local full service station in Maracaibo, just 400 km from Bonaire.

As I said, TWR back then was "dismissive" of any station except their own.
 
Yeah, that sounds like their attitude. Besides owning stations in Ecuador back in the later 60's, I compiled and edited several editions of the Latin American AM log for the National Radio Club, and there was no station on 800 that went bankrupt. Not in the Netherlands Antilles, not in Venezuela, Colombia, Panamá, Ecuador, Central America or anywhere in the Caribbean.

Or a local full service station in Maracaibo, just 400 km from Bonaire.

As I said, TWR back then was "dismissive" of any station except their own.
Very interesting, not surprising.
 
This was later in the 70s, but my foggy brain seems to remember the RN broadcasts being cut to 70 minutes. I remember Tom Meijer doing a separate bilungual "Happy Station 70 (referring to the length)" where he spoke i a mellow tone, I guess getting his Carribean vibe on.
I think you are correct. My own foggy memory recalls that when RN's medium wave block on 800 kHz was moved up to 2300 UTC in the late 70s it was also cut to 90 minutes. Spanish would have been at 2300, English at 2335, and the 20 minute newscast in Dutch at 0010. On days when the Spanish and English segments were combined into the bilingual show it would have resulted in a 70 minute program before the Dutch newscast.

I'll have to dig into my "archive" of radio stuff to verify. I do recall the RN medium wave broadcasts were gone by 1980.
 
The coverage daytime was not that bad... it ran from the coastal area East of Caracas to Eastern Panamá, a distance of nearly 1000 miles and including Caracas, Maracaibo, Santa Marta, Barranquilla, Cartagena and a bunch of other coastal cities. From what I recall, from working on some projects in Venezuela in the 70's and visiting often in the late 60s, the signal only made it 30 to 40 miles inland at best.

I don't think that the Netherlands entity leased the station... I think TWR gave the time as an exchange for the licensing and permits.

Did they actually do a Dutch service? The Netherlands Antilles speak Papaiamento, along with English and Spanish, but I never ever heard "real" Dutch spoken there, even if technically Dutch is one of the three official languages.
The Dodger's great closing pitcher Kenley Jansen is from the NA and speaks all the local languages.
 
However in the 1960s and early 70s TWR also clashed with what was then XELO, a border blaster that ran English language religion at night.
By the early 70's XELO had become XEROK, X-Rock 80 and tried to replicate the success of the later 60's and 70's success of KOMA. But by then nearly every market, even smaller ones, had a local Top 40 and it did not really succeed... plus KOMA's big billing was from movies and shows and that radio money did not spend on a distant station any more.
 
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