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(USA) High Power AMs

The Dodger's great closing pitcher Kenley Jansen is from the NA and spreaks all the local languages.
That's always commendable. One of my daughters is a true polyglot, being able to do legal work in five or six languages and getting along in a couple more. I'm stuck with two proficient ones and minimal "getting along" in a couple of others.
 
That's always commendable. One of my daughters is a true polyglot, being able to do legal work in five or six languages and getting along in a couple more. I'm stuck with two proficient ones and minimal "getting along" in a couple of others.
Someone please refresh my memory...didn't PJB replace their 500 kw non-directional facility with a 100 kw directional system so that they could target the AM signal where it was really needed, seeing that they had a dozen or so FM translators located in significantly populated areas?
 
Someone please refresh my memory...didn't PJB replace their 500 kw non-directional facility with a 100 kw directional system so that they could target the AM signal where it was really needed, seeing that they had a dozen or so FM translators located in significantly populated areas?
They did switch to a 100kW transmitter sometime back, but within the last few years installed a 440kW transmitter directionally aimed at Cuba. I think they do Portugese to Brazil with a different pattern in the early morning.

Back in the 70s and 80s, even though PJB covered a wide swath of North America, they didn't seem to indicate on-air that North America was a particular target audience (though for donors, I'm sure it was)
 
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Someone please refresh my memory...didn't PJB replace their 500 kw non-directional facility with a 100 kw directional system so that they could target the AM signal where it was really needed, seeing that they had a dozen or so FM translators located in significantly populated areas?
The power was dropped to 100kw in the 1990s. However about three years ago a new Nautel transmitter was installed running as much as 440kw on certain beams, and 200kw on others.
 
Someone please refresh my memory...didn't PJB replace their 500 kw non-directional facility with a 100 kw directional system so that they could target the AM signal where it was really needed, seeing that they had a dozen or so FM translators located in significantly populated areas?
I understood that they had several issues, the first being that the 60's transmitter was no longer maintainable and very expensive to generate power for.
 
They did switch to a 100kW transmitter sometime back, but within the last few years installed a 440kW transmitter directionally aimed at Cuba. I think they do Portugese to Brazil with a different pattern in the early morning.
I never understood the Portuguese programming on medium wave, as no matter what the power, they only had a narrow window of opportunity to reach people in NW Brasil in the pre-sunrise to sunrise hours when there was skywave. That's a big distance to cover, and very little population in the areas of Brasil they covered.

More likely they got SW listening, as Brasilian SW stations were still very active in that era, particularly in Northern and Rural Brasil.
 
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Good Info. Too bad that article doesn't specify whether that 440 kw is non-directional or directional. 440 kw fed into a three tower phased array could give them an ERP upwards of 1.5 Mw in the desired direction
My understanding is that it's directional, aimed straight at Havana.
 
They did switch to a 100kW transmitter sometime back, but within the last few years installed a 440kW transmitter directionally aimed at Cuba. I think they do Portugese to Brazil with a different pattern in the early morning.

Back in the 70s and 80s, even though PJB covered a wide swath of North America, they didn't seem to indicate on-air that North America was a particular target audience (though for donors, I'm sure it was)
Back in the day TWR alternated with Radio Nederland on 9590 kHz in the 31 m band with a signal targeted at North America.
 
My understanding is that it's directional, aimed straight at Havana.
Actually, it would be aimed at somewhere between Cienfuegos and Camagüey, which would center it on the population of all of Cuba, which is over 800 miles wide. Havana would be slightly to the western side of the lobe.

I also wonder if the daytime signal makes it across the island to La Habana and Matanzas and the northern coastal areas of Cuba, or whether it is usable only along the southern and southeastern coastal areas. Even the local 50 kw AMs have trouble making it across the central mountain zones in much of Cuba.

Look at the topography of Cuba and you can see the likely coverage in the daytime would only be the southern coastal flatlands:

 
Actually, it would be aimed at somewhere between Cienfuegos and Camagüey, which would center it on the population of all of Cuba, which is over 800 miles wide. Havana would be slightly to the western side of the lobe.

I also wonder if the daytime signal makes it across the island to La Habana and Matanzas and the northern coastal areas of Cuba, or whether it is usable only along the southern and southeastern coastal areas. Even the local 50 kw AMs have trouble making it across the central mountain zones in much of Cuba.

Look at the topography of Cuba and you can see the likely coverage in the daytime would only be the southern coastal flatlands:

There is no Daytime schedule for TWR, it operates 7pm-1am Eastern in English and Spanish, and 4:00am-7:30am in several languages for Brazil.
 
There is no Daytime schedule for TWR, it operates 7pm-1am Eastern in English and Spanish, and 4:00am-7:30am in several languages for Brazil.
Strange. The single lobe aimed at Cuba with what is likely over a megawatt could easily cover most of the southern coastal areas nicely in the daytime.

When I was in Puerto Rico, we often spent weekends at Guánica. At that SW coastal town, the coastal Venezuelan stations, about 600 miles away, were nearly local strength if they were on frequencies not used in that part of PR. Most were 10 kw, with only a few having higher power. So Bonaire to coastal Cuba would be like a "local station" over the salt water path with that kind of power.

I don't get the Brazilian broadcast; never have. The only areas you can cover from 4 AM to 7 AM are mostly post-sunrise or nearly so; sunrise in the tropics is near 6 AM year round and most of Brazil's populated zones are going to be in daylight by 5 AM in Bonaire.

Bonaire is nearly 1,300 miles from the nearest Brazilian population center of Manaus, over rough terrain much of the way. The closer areas are very sparsely populated.

This all sounds like the typical arrogant evangelistic attitude of "we're gong to convert them whether they like it or not". A total contrast to the lovely manner of working of the HCJB folks, who built schools, clinics and job training facilities for their areas of influence.

That said, my story of visiting the facility in the later 60's when we were trying to get them to do something so as not to kill all the Caribbean Basin and beyond stations on 800, includes a visit to the transmitter site. They wanted to prove that they were "so much better" than us money grubbing commercial stations and "here is our multi-million dollar site to prove it". While there, the medium wave rig went off the air; big rigs like that have big relays and make some loud nose when turning off. Did they immediately push "plate on"? No. The engineers knelt in front of the transmitter, said a brief "Lord, bring our voice back to our people" prayer, then hit the plate button and the transmitter went right back on.

The facility was so amazingly clean you could have eaten off the floor. Technically, they did a marvelous, spectacular job.
 
Strange. The single lobe aimed at Cuba with what is likely over a megawatt could easily cover most of the southern coastal areas nicely in the daytime.

When I was in Puerto Rico, we often spent weekends at Guánica. At that SW coastal town, the coastal Venezuelan stations, about 600 miles away, were nearly local strength if they were on frequencies not used in that part of PR. Most were 10 kw, with only a few having higher power. So Bonaire to coastal Cuba would be like a "local station" over the salt water path with that kind of power.

I don't get the Brazilian broadcast; never have. The only areas you can cover from 4 AM to 7 AM are mostly post-sunrise or nearly so; sunrise in the tropics is near 6 AM year round and most of Brazil's populated zones are going to be in daylight by 5 AM in Bonaire.

Bonaire is nearly 1,300 miles from the nearest Brazilian population center of Manaus, over rough terrain much of the way. The closer areas are very sparsely populated.

This all sounds like the typical arrogant evangelistic attitude of "we're gong to convert them whether they like it or not". A total contrast to the lovely manner of working of the HCJB folks, who built schools, clinics and job training facilities for their areas of influence.

That said, my story of visiting the facility in the later 60's when we were trying to get them to do something so as not to kill all the Caribbean Basin and beyond stations on 800, includes a visit to the transmitter site. They wanted to prove that they were "so much better" than us money grubbing commercial stations and "here is our multi-million dollar site to prove it". While there, the medium wave rig went off the air; big rigs like that have big relays and make some loud nose when turning off. Did they immediately push "plate on"? No. The engineers knelt in front of the transmitter, said a brief "Lord, bring our voice back to our people" prayer, then hit the plate button and the transmitter went right back on.

The facility was so amazingly clean you could have eaten off the floor. Technically, they did a marvelous, spectacular job.
 
Very interesting. I couldn't tell you if it's budgetary or not wanting to tweak the Cuban government enough for them to build a Rebelde chorus against it. I've been told (and listening seems to have confirmed) that TWR does not use native Spanish speakers.
Brazil.....no clue. Evangelicalism is getting big there, and it was evangelicals that elected Bolsonaro as they elected Trump in the U.S. I don't think it's TWR's version of evangeliclism though....they seem more institutionally Baptist as opposed to independent charismatic.

I also remember HCJB broadcasting Japanese to Brazil.

Wolfman Jack claimed in his book that XERF's transmitter was cleaned daily and the facility was similarly pristine.

Here is Scott Fybush's accounting on visiting PJB in the late 90s. A selection from a decade of visits to tower and studio sites in the Northeast and beyond
 
That prediction has been made since the 70's. Hasn't happened yet.

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.
The outlook isn't sanguine for any type of OTA radio. It's an industry that has seen revenues nearly halved since 2005, and TSL has dropped as well, even to FM. As advertising revenues drop, the cost of the infrastructure (FM as well as AM) stays the same or increases.

I don't see OTA radio lasting another two decades, except a handful of straggler FMs in each metro perhaps.

In 2011 the nice young 20-something barista in downtown Renton saw I had a walkman on my arm (a Sony Sports walkman, I was taking it to work) and she asked me what it was. I said it's a radio. "What's a radio?" she asked. And this was 2011. Just a decade ago. I know there are surveys about how millennials consume OTA radio by the metric ton, but I'm not seeing much evidence of it.

As far as my comment about higher AM transmitting power fighting RFI, all I know is that whenever my radios are in the vicinity of an RFI source, 50KW stations like KIRO ride over it with a lot more readability (even killing it, in many cases) than a 1 KW station will.
 
The outlook isn't sanguine for any type of OTA radio. It's an industry that has seen revenues nearly halved since 2005, and TSL has dropped as well, even to FM. As advertising revenues drop, the cost of the infrastructure (FM as well as AM) stays the same or increases.

I don't see OTA radio lasting another two decades, except a handful of straggler FMs in each metro perhaps.

In 2011 the nice young 20-something barista in downtown Renton saw I had a walkman on my arm (a Sony Sports walkman, I was taking it to work) and she asked me what it was. I said it's a radio. "What's a radio?" she asked. And this was 2011. Just a decade ago. I know there are surveys about how millennials consume OTA radio by the metric ton, but I'm not seeing much evidence of it.

As far as my comment about higher AM transmitting power fighting RFI, all I know is that whenever my radios are in the vicinity of an RFI source, 50KW stations like KIRO ride over it with a lot more readability (even killing it, in many cases) than a 1 KW station will.
Hopefully (I'm sure) it was just her upbringing, because any 20-something in 2011 would've been born in the radio-happy 80's and 90's. I think two decades is a unnecessarily grim estimate considering there are 6 thousand FM stations left, and 4k AM stations, but I do agree things are going downhill in that department, just slower.

Streaming? It's pretty good when it works, and it's everywhere (except for geo-fencing), but some companies build their cell towers in nonsense locations meaning that the areas that need to be covered might have a donut hole. T-mobile has such an odd spot at my local convenience store. Still, I suppose the technology is fairly robust, but c'mon cell phone providers!

Logic would dictate that KGAB would be the strongest in my town, but it is in-fact KVAM, on the other side of the dial; there is less noise, and it's 10kw compared to 8.5kw, so I hear you. One source of RFI noise that absolutely kills AM around is the "Magic Carwash" on the north-side of town, and it uses a whole bunch of modern equipment which generates noise. Once you pull out from the carwash the stations all come back.
 
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The outlook isn't sanguine for any type of OTA radio. It's an industry that has seen revenues nearly halved since 2005, and TSL has dropped as well, even to FM. As advertising revenues drop, the cost of the infrastructure (FM as well as AM) stays the same or increases.
Agree with you about AM because as we've all heard before; AM is simply aging-out. I don't agree that FM will go the same way of AM. The quality and coverage is, and will remain, still good enough for in vehicle listening well into the future.
I've not seen quantifiable statistics which claim radio TSL has dropped. There are definitely less dedicated listeners under 30, but that's because they get news, music, and audio entertainment from competing on-line sources.
I don't see OTA radio lasting another two decades, except a handful of straggler FMs in each metro perhaps.
For those able to bolster advertising from remaining local businesses, small market FM's will still be around. Several rural communities don't have ready access to public Internet for streaming, or don't want to pay for subscription services.
In 2011 the nice young 20-something barista in downtown Renton saw I had a walkman on my arm (a Sony Sports walkman, I was taking it to work) and she asked me what it was. I said it's a radio. "What's a radio?" she asked. And this was 2011. Just a decade ago. I know there are surveys about how millennials consume OTA radio by the metric ton, but I'm not seeing much evidence of it.
You have to admit, even if they listened to the radio on a frequent basis, a Sony Walkman is a museum piece.
As far as my comment about higher AM transmitting power fighting RFI, all I know is that whenever my radios are in the vicinity of an RFI source, 50KW stations like KIRO ride over it with a lot more readability (even killing it, in many cases) than a 1 KW station will.
If you lived in Issaquah, Bellevue, or Monroe, you couldn't say the same.
 
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