Monday, September 01, 2025

Brazil on Shortwave

 

Special thank you to Ray Robinson and Jeff White for sharing this week's edition of Wavescan.  Shortwave broadcasts continue to dwindle from South America; however, Brazil remains a favorite to monitor.

Jeff:  Our featured country this week is Brazil – the largest country in South America.  Back in 2021, we brought you a three-part series on the early history of wireless and medium wave radio in Brazil, but we’ve never covered the shortwave scene there before.  So here to rectify that is Ray Robinson, in Los Angeles.
Ray:  Thanks, Jeff.  And yes, Brazil is indeed a country of superlatives, larger than the continental United States.

The Amazon River is thought by many to be the world’s longest river, originating more than 4,000 miles inland from the Atlantic coast.  Large ocean-going vessels can ply the Amazon River for a thousand miles inland, and the river is navigable for smaller ships for another thousand miles further.  This huge river system disgorges fresh water at the rate of 18 million tons every minute, sending it out for a distance of 250 miles into the Atlantic Ocean.

Iguazu waterfalls (photo via Wikipedia)

The dramatic Iguazu waterfalls lie at the border between Brazil and Argentina.  The water at Iguazu plunges from a height of more than 200 feet, higher than the Niagara Falls.  These South American falls stretch across the landscape for more than a mile.  In season, the water tumbling over the edge of the cascading cliffs at Iguazu is greater in volume than that of all the other major water falls throughout the world combined, and the thunderous, tumultuous roar from Iguazu can be heard for miles.

Most of the major cities in Brazil lie along the Atlantic coast, with the largest being Sao Paulo (population 22 million) and the second largest Rio de Janeiro (population 12 million).  Only Brasilia, founded as the national capital in 1960 and now with a population of 3½ million, is located inland, some 1,000 miles from the ocean.

As we’ve told you previously, the medium wave scene in Brazil dates back to an experimental demonstration station that was set up in Rio de Janeiro in 1922.  In the early days when only a very few wealthy Brazilians owned receivers, radio clubs were formed in many areas which supported nonprofit radio stations through contributions from the members.  These were often called Radio Clube do and the name of the town or city, or sometimes Radio Sociedade do … wherever.  By the 1930’s, however, more Brazilians owned radio receivers, and commercial radio stations came on the air.  Gradually the radio clube and radio sociedade stations switched to private commercial ownership, although a few do still survive.



As the use of medium wave began to proliferate, so did the use of tropical band shortwave and even the higher shortwave bands, for domestic purposes.  Some stations solely used shortwave, while others simulcast their medium wave programming on one or more shortwave frequencies.  Some Radio Nacional stations were run by the government and carried less advertising, similar to the CBC in Canada or PBS in the USA.  Educational stations were also run by the Catholic Church.  But most stations were commercial, and with huge territory to cover, shortwave was the most efficient way of doing it.

By the early 1970’s, over 200 shortwave stations were listed in Brazil in the WRTH, all targeting domestic audiences, mostly in Portuguese, but also a few in indigenous Indian languages.  Transmitter powers were typically around 1-5 kW on the 90- and 60-meter tropical bands, but as much as 50 kW on the higher international shortwave bands, where some 2-3 dozen stations operated, all the way from 49 meters right up to the 16-meter band.  The only other countries to make such extensive use of shortwave for domestic purposes were Peru and Indonesia, although the transmitter powers in Brazil were generally higher.

The government of Brazil from 1964-1985 was a military dictatorship, and in the early 70’s, they became concerned at the amount of cold war propaganda that was being transmitted to Brazil in Portuguese by foreign countries, especially socialist or communist ones such as Cuba.  Foreign broadcasts in Portuguese were easily heard by Brazilians who were very used to using shortwave – it was part of their culture – and the government feared that such foreign broadcasts might start winning over hearts and minds.

The dictatorship already had a couple of very grandiose infrastructure projects under its belt – the 2,600-mile-long Trans-Amazonian Highway and the Rio-Niterói Bridge, which at over 8 miles long was, at the time of its construction, the second longest bridge in the world, second only to the Lake Pontchartrain Causeway in Louisiana.  So, in the early 70’s, they decided to undertake one more major infrastructure project – the “High Power Broadcasting System” – for Radio Nacional de Brasilia – a station which had been inaugurated in 1958, but which at that time only had transmitters in the major cities.



A 1,200-acre site was selected at the Parque do Rodeador, or Rodeo Park, about 30 km (18 miles) northeast of downtown Brasilia in the Brazilian Federal District.  It is well away from any other telecommunications services, and sits on the highest point in the district, 4,400 feet above sea level, surrounded by small farms.  Much of the property had to be cleared of tropical rain forest.

Initial construction was completed in 1974, at a cost, adjusted for inflation, of half a billion Brazilian Reals, equivalent to about US$90 million.  The High-Power Broadcasting System at the Parque do Rodeador was inaugurated on March 11, 1974 by then president Emilio Médici – who arrived by helicopter and in short order opened the station himself by turning on a medium wave transmitter, and the Minister of Communications who was with him turned on a shortwave one.

Radio Nacional 


A 1,200-acre site was selected at the Parque do Rodeador, or Rodeo Park, about 30 km (18 miles) northeast of downtown Brasilia in the Brazilian Federal District.  It is well away from any other telecommunications services, and sits on the highest point in the district, 4,400 feet above sea level, surrounded by small farms.  Much of the property had to be cleared of tropical rain forest.

Initial construction was completed in 1974, at a cost, adjusted for inflation, of half a billion Brazilian Reals, equivalent to about US$90 million.  The High-Power Broadcasting System at the Parque do Rodeador was inaugurated on March 11, 1974 by then president Emilio Médici – who arrived by helicopter and in short order opened the station himself by turning on a medium wave transmitter, and the Minister of Communications who was with him turned on a shortwave one.

By 1979 the site housed 6 x 250kW Brown Boveri shortwave transmitters from Switzerland, and also 2 x 300kW medium wave transmitters which could provide a combined output power of 600kW, sufficient to cover the entire country at night on 980 kHz.  The shortwave transmitters were used for both domestic and international coverage, the primary frequencies being 6180 and 11780 kHz.  They also had a high-power FM transmitter on 96.1 MHz for the city of Brasilia.  

For the international broadcasts they used five languages - English, German, French, Spanish & Portuguese.  Programs were produced first in Portuguese, and then translated into each of the other languages.  They mostly consisted of news, but also included politics, the economy, science and technology, culture and the arts, Brazilian music and listeners' letters.  Broadcasts ran seven days/week, with two hours in each language, scheduled to reach listeners during the evenings in their target areas.  In the days before web SDR's, Brazilian embassies around the world were used to monitor reception quality, and recordings were sometimes played back by telephone, so the technical staff in Brasilia could hear what the broadcasts sounded like.



Eventually, though, budget cutbacks and failing equipment meant the end of the international service.  Transmitter tubes failed, and replacements were no longer available.  So, they had to reduce the number of transmitters in service, and the Amazon became the priority for coverage instead of international audiences.  The name of the station was then changed to Radio Nacional do Amazonia, broadcasting exclusively in Portuguese.

In 2018, Parque do Rodeador was classified as a critical national infrastructure resource, because in the event of a major catastrophe (such as floods, blackouts, or natural disasters), it's the only place from where the government can broadcast to the entire country, without dependence on satellites or Internet infrastructure.

This station has always been a good verifier, with QSL cards featuring iconic Brazilian tourist scenes including the seven falls at Iguazu, Rio de Janeiro with the statue of Christ the Redeemer, the Amazon rain forest, and Brazilian beaches.

Today, Radio Nacional do Amazonia still operates on the same two frequencies as back in the 1970’s – 6180 and 11780 kHz, but now with 100 kW on each.

And on April 1st this year, they reintroduced some brief programming in English and Spanish in DRM mode at 0150 UTC daily – 5 minutes in each language.

There are still six other regular private broadcasters left who transmit on shortwave, plus a handful of occasional come-and-go reactivations.  The ones you may still be able to hear are:

Radio Brasil Central from Goiânia with 10 kW on 4985 and 11815 kHz,
Radio Clube do Para from Belém with 2 kW on 4885 kHz,
Radio Clube Riberão Preto from the town of Riberão Preto on 15415 kHz,
Radio Inconfidencia from Belo Horizonte with 5 kW on 6010 & 15190 kHz,
Radio Nove de Julho from São Paulo with 10 kW on the off-channel frequency of 9819 kHz, and
Voz Missionaría from Camboriú with 10 kW on 5940, 9665 and 11750 kHz.

Back to you, Jeff.
(NWS 862/Ray Robinson)