Category Archives: Guest Posts

Guest Post: Photo and Video Tour of Rádio Nacional da Amazônia

Many thanks to SWLing Post contributor, Martin Butera, who shares the following guest post which was originally published in two parts in the September and October 2019 issue of the British DX Club magazine.

Martin notes that this report was also presented live by Chrissy Brand (EDXC Secretary General – editor responsible for the BDXC newsletter) at the 2019 European DX Council EDXC Conference (September 6 – 9) in Andorra.

In commemoration of its 42nd anniversary, Martin has put together this impressive report with sixty photos and five videos of Radio Nacional da Amazonia. Enjoy:


Visit to Rádio Nacional da Amazônia

Rádio Nacional da Amazônia, the largest complex of medium transmitters and short wave transmitters in Latin America and the fifth most powerful transmitting station in the world.

Report and research by: Martín Butera
Photographs and Video (under study) by: Ligia Katze
Photographs and Video (antenna field) by: Mark Van Marx
English adaptation and correction by: Sudipto Ghose (VU2UT)

Subject index and table of contents

1. Introduction (Brief History of the Rádio Nacional da Amazônia).
2. What is the Rádio Nacional da Amazônia? (Interview with the programme producers of the National Radio da Amazônia, Luciana Couto, Taiana Borges and Solimar Luz) – Photos and Video.
3. Interview with broadcaster Beth Begonha
4. Visit to the Mixing Room with Luciano Maia
5. Brief introduction to the antenna field
6. Antennas
7. Transmission Lines
8. Transmitter room
9. Transmitter monitoring and control room
10. Electrical part
11. Transmitter power supply panel
12. National Radio Brasilia AM 980 Khz
13. Final notes by Martin Butera
14. Acknowledgments
15. Review with information from the authors of this report

1. Brief Introduction to the History of “La Rádio Nacional da Amazônia”.

The Rádio Nacional da Amazônia transmits to more than half of the Brazilian territory in short waves, within the frequency range of 11,780 kHz to 6,180 kHz.

The Rádio Nacional da Amazônia is a popular communication media channel that strengthens the link between Amazonian communities, valuing and spreading the cultural diversity of the region. These functional guidelines are born out of the demands of the Amazonian population for social inclusion.

Inaugurated on September 1, 1977, the station was established by the military government under the so-called National Security Doctrine. The objective was to prevent the Amazonian population from continuing to listen only to the sound of the radios of the communist countries, which escaped censorship, for example: Radio La Habana, from Cuba; Moscow International Radio of the former Soviet Union; Radio Tirana of Albania, among others
Two years before the start of the transmission of the Rádio Nacional da Amazônia, in December 1975, Radiobrás was established as a public company that began to centrally administer all radio and television stations throughout the country of Brazil. Under the command of General Lourival Massa da Costa, with the new station, the agency had the mission of “integrating the Amazon with the rest of the country”, through the medium of radio.

During the reign of the military government, massive human rights violations took place. The military regime crushed press freedom and severely repressed the political opposition. The military government formally adopted nationalism, economic development and anti-communism as official mission. Throughout its existence, especially during the 1960s and 1970s, the Brazilian military dictatorship received logistical and economic assistance from the United States government in what was called the Condor Plan, establishing similar dictatorships within the broader framework of the Cold War.

Beginning in the 1980s, military hegemony entered into crisis due to chronic inflation and the progressive collapse of military regimes in Argentina, Peru and other neighbours in South America. In 1985, the last indirect election was held, disputed only by civilian candidates, and the MDB candidate, Tancredo Neves, won by a wide margin. Neves, however, died before taking office, being replaced by José Sarney.

Sarney assumed the presidency on March 15, 1985, ending the military regime. After his election, he restored civil liberties and scheduled the approval of a new constitution in 1988, restoring the direct election of the president of the republic, and initiating the final transition to democracy.

The dictatorship that began on March 31, 1964, with the coup d’état of democratic president João Goulart, engulfed Brazil into two decades of darkness, which kept five military presidents in power, leaving behind a trail of hundreds of murders. Innumerable people disappeared and so many were tortured, of which there is still no exact figure due to the lack of records.
On June 12, 2008, Radiobrás ceased to exist and all the radio stations that were part of the company, including the Rádio Nacional da Amazônia, came under the control of the Empresa Brasil de Comunicação (EBC), which continues to function to this day.

Empresa Brasil de Comunicação (EBC), a public company organised as a private corporation, with 51% of its shares owned by the Union, created by Law 11.652 / 2008. The company’s mission is to implement and administer the system of public communication as envisaged in the Federal Constitution in its article 223.

Time passed, the struggles for democracy was started and the broadcaster came to fulfill the strategic objective of dissemination of information in a democratic country, now bringing true messages and correct information to the population of the Amazon, a region that was previously forgotten.

Today, the station is a means to promote and safeguard the rights of the citizen and communication between listeners. “The Rádio Nacional da Amazônia, has managed to change one of the most shameful and sad times in the recent history of Brazil “the military dictatorship”.

Thus, in 2012, with the report on crimes against indigenous peoples in dictatorship, published in August 2012, the Rádio Nacional da Amazônia won the 34th Vladimir Herzog Journalist Award for Amnesty and Human Rights, in the category of Radio. The reports of human rights violations, signs of torture, aggression and deaths that are hard to erase from memories marked the period of the military dictatorship in Brazil. The report was produced by the reporter Maíra Heinen, with the help of sound engineer Marcos Tavares.

The Vladimir Herzog Journalism Prize for Amnesty and Human Rights is a Brazilian journalistic award that is awarded annually to professionals and media that have excelled in the safeguarding democratic values, rights of the citizen and human and social rights, as well as personalities, professionals and media communication that stands out in the defense of these fundamental values.

2. What is the Rádio Nacional da Amazônia?

Interview with the programme producers of the National Radio da Amazônia, Luciana Couto, Taiana Borges and Solimar Luz) – Photos and Video.


Photo: Martín Butera, while writing the report on National Radio da Amazônia, at the planning stage of the work of going through the studios to visualise the technical part as well as the interviews with different producers and broadcasters.


Photo: Martín Butera and the producers of the Radio Nacional da Amazônia, Luciana Couto, Taiana Borges


Photo: Martín Butera and the producers of the Radio Nacional da Amazônia, Luciana Couto, Taiana Borges

Here is a brief summary of the conversations with the producers Luciana Couto, Taiana Borges and Solimar Luz, about what the National Radio da Amazônia means for them (to find out more the reader can go to the link for the full video interview, conducted in Portuguese language)

Videos by Ligia Katze

The producers mentioned that the programming pattern is almost entirely created by the listeners themselves, due to the close relationship maintained between them and the radio producers and announcers.

The producers impressed upon us that, we must think about the immensity of the peoples that inhabit the Amazon, that until today the radio is used to leave messages to the listeners themselves to their relatives and friends, since in those places the only message that is received is the radio transmission itself and such situation underlines the importance of maintaining the shortwave service.

Photo: Luciano G. Maia, in-charge of public relations of the company EBC, Martín Butera and the producers of the Radio Nacional da Amazônia, Luciana Couto, Taiana Borges and Solimar Luz.

3. Interview with broadcaster Beth Begonha

Presented from Monday to Friday from 8 a.m. to 10 a.m., the program carries the diverse views on education and struggle of the people related to the history and culture of the Amazon.

The listeners participate in the program through feedback via letters that offer suggestions, ask questions and request for songs. There is also regular participation of reporters and interviewees directly from the Amazon region.

The broadcaster Beth Begonha has been conducting the program called “Brazilian Amazon” since 2003. We were able to interview her in a relaxed atmosphere in the studio itself, during the intermissions in the transmissions.

Beth is a very sought-after announcer, since she herself made numerous trips to visit indigenous populations in towns and communities, establishing a strong bond and very beautiful relationship with them.

Through the microphones of the National Radio of the Amazon, Beth Begonha speaks with the awareness of a person who lived and experienced the reality of the Amazon. The program discusses environmental issues and highlights the need to assess the cultural identity of indigenous communities, and of all the people who live on the banks of the great Amazon River.
Graduated in journalism in an Amazonian city, Beth says she has been through adverse conditions and her story serves as a motivation to guide education in the Brazilian Amazon and encourage listeners to return to school. “I studied and completed my university course with great struggle, and I believe that this is also an important element in this endeavour, which has had many beautiful results.”

Beth Begonha tells me “Everything I know about the indigenous people is what I learned from them. When I started the project of the Brazilian Amazon, a program that I present and produce in the Rádio Nacional da Amazônia, I had very clear objectives that we should achieve as a media space : integrate the different peoples that live in the Amazon, with their cultural diversity, specific topics, promoting knowledge and increasing interaction among these populations, this also included indigenous communities, this space has always been designed to be occupied by the Indians, not for someone who speaks for them. ”

Beth Begonha rounds up: “It was not a difficult task, I must confess, for the receptivity of these communities, for their desire and need to be seen and heard. The greatest difficulty was mine, because despite working in communication for many years, even in the Amazon, I had no true knowledge of the Indians. ”

The Beth Begonha program performs unprecedented work, includes indigenous peoples into the production of the program, opening a space that values these Brazilians.
The musical part is not only dedicated to popular and successful Brazilian songs, here the listeners have the opportunity to listen to songs that are produced directly inside the core areas of Amazon.

Beth Begonha’s program has created a bridge of important relationship of other listeners with indigenous peoples, increasing empathy and respect for their culture.

This relationship with the indigenous population led Beth Begonha to produce among others a transmission from outside the studios, it was when I visited the Xingu Indigenous Park in 2007, where he covered the visit of the then Minister of Justice Tarso Genro (Brazilian lawyer, journalist and politician affiliated with Workers’ Party, who is currently the governor of the state of Rio Grande do Sul).

Beth Begonha’s program not only had the brave idea of transmitting directly from the Amazon rainforest and different indigenous camps in Brazil, it has also transmitted from several meetings and conclaves that dealt with the biodiversity of the Amazon.

One of these transmissions was the transmission that took place from June 18 to 22, 2012 during “Rio + 20”, the biggest environmental event of the last decade.

Photo: Ligia Katze, the photographer accredited, in the studios and Martín Butera, interviewing the broadcaster of the National Radio da Amazônia, Beth Begonha.

Photo: Martín Butera, interviewing the broadcaster of the National Radio da Amazônia, Beth Begonha, next to him is the photographer Ligia Katze.

Photo: Martín Butera, next to the broadcaster of the National Radio da Amazônia, Beth Begonha alongwith the shift operator.

Photo: Martín Butera, next to the main console table of the studio of the National Radio da Amazônia

Below a small fragment on video (Portuguese language) can be seen, about this talk with the announcer of the National Radio of the Amazon “Beth Begonha”.
Videos by Ligia Katze

4. Visiting the mixing room

Together with Mr. Luciano G. Maia, in charge of public relations of the company EBC, I had the opportunity to tour the entire modern facility. Here you can see the impressive mixing consoles of all radio and even television signals.


Photo: general mixing table of the company EBC


Photo: Martín Butera, with the EBC mixing shift operator

Photo: Martín Butera, alongside the modern mixing racks

Video by Ligia Katze:

5. Brief History of the Radio Nacional de Brasilia Park

The Rodeador Park in Brasilia Federal District. It is the largest complex housing medium wave and short wave transmitters in Latin America. It transmits the signals of the National Radio AM of Brasilia and the National Radio of Amazonia for whole of Brazil.

The transmitter of the National Radio AM of Brasilia works only during the night, when the signal is transmitted throughout the country. During the day, the Brasilia AM National Radio signal is transmitted from the SIA Transmitter Park, covering only the Federal District and its surroundings. This is due to the difficulty of transmitting a medium-wave signal throughout Brazil during the day.

The visit to the antenna field is absolutely incredible experience; the structure of the park without a shade of doubt is colossal.

From afar, you can already see the imposing towers each 150 meters high.
Everything is perfectly well maintained and a team of very dedicated persons and professionals work round the clock in the field of antennas. These professionals are responsible for upholding and maintaining the quality of the signal.

While there is a great contrast between the modern studios located in the center of Brasilia to the transmitters and the antenna in a field located 34 kilometers away, the transmitters look like more museum pieces. But to be honest I must say that everything works perfectly well, thanks to the dedication of the professionals who maintain these transmitters on a permanent basis.

The antennas that are an elaborate and complex installation, assure the Brazilian government the possibility of having radio coverage to the remotest areas of the country, as well as the possibility of reaching all the five continents.

In the above backdrop, during the year 2018, the “Cabinet of Institutional Segurança da Presidência da República (GSI)”, the “Parque do Rodeador” officially classified the antenna field as vital support infrastructure during critical situations, natural disasters and emergencies, to be used as and when the Brazilian population encounters a situation of collapse in communications.

Installed on March 9, 1979, the areas of antenna field houses four sets of giant antennas, one of which is 142 meters high. The other three sets have higher towers, reach 147 meters and are used for transmitting in short waves (OC). In addition to the vertical antenna used for medium wave transmission, the park has the dipole curtain antenna reinforcement for short wave transmission.

6. Antennas

We were received by Ismar Do Vale Junior, who is the principal telecommunications engineer and the technical manager responsible for the maintenance coordination, of the “Parque do Rodeador” antenna field, we were also received by the Radio and Television Engineer Mr. Manoel Caetano dos Santos and finally we were escorted by a valued guest Orlando Perez Filho “PT2OP”, former Executive Director of LABRE DF (League of Brazilian Lovers of Rádio Emissão).
The antenna field has a set of antennas for the emission of short waves of Rádio Nacional da Amazônia, divided into 4 different antennas referred to as: C1, C2, C3 and C4.

The antennas are suitable for transmission of a maximum power of 300 kW, however it is always operated with half power of 150 kW. Currently such power was reduced to 75 kW, this was due to an event that occurred in March 2017, which we will go into detail of this when we talk about the electrical part.

Videos by Mark Van Marx (Marxos Melzi)

Photo: a satellite image of the antenna field.

Photos by Mark Van Marx (Marcos Melzi)


Photo 0014: The engineer Ismar Do Vale Junior displays the map of the antenna layout and discusses in detail one by one, to us.


Photo: Original layout map of the antenna setup of the Rádio Nacional da Amazônia
As mentioned earlier, the set of short-wave “dipoles” of the Rádio Nacional da Amazônia consists of 4 different of antennas, which are called C1, C2, C3 and C4, each of which is fed separately. I will give the details now.

C2 and C3

The antenna installations C2 and C3 have the same structures and dimensions and are operated at frequencies close to 6 MHz. Currently, antenna C2 is used to transmit the signal from the National Radio of the Amazon at 6,185 kHz and the other antenna C3 is on standby and not transmitting.

C1 and C4

The structure and dimensions of antenna installations C1 and C4 are also identical. They are designed so that they can transmit on three frequencies that is on 9, 11 and 15 MHz. However, at present, only the antenna C4 is active, transmitting the signal from the National Radio of the Amazon on the frequency of 11,780 MHz.


Photo: Martín Butera, next to the sign, which prohibits access to the shortwave antenna field entrance, due to the presence of high RF energy.


Photo: from behind, Martín Butera, engineer Ismar Do Vale Junior, Orlando Perez Filho “PT2OP”, former Executive Director of LABRE DF (League of Brazilian Lovers of Rádio Emissão) and Engineer Manoel Caetano dos Santos, beginning the tour of the antenna field Photo: view of different angles of the shortwave antennas and the feeders.


Photo: view of different angles of shortwave antennas


Photo: view of different angles of shortwave antennas


Photo: view of different angles of shortwave antennas


Photo: view of different angles of shortwave antennas


Photo: view of different angles of shortwave antennas


Photo: view of different angles of shortwave antennas


Photo: view of different angles of shortwave antennas

7. Transmission lines

Since each antenna system is fed separately, each of them has its own identical transmission line. In the photographs we can see that they are bifilar lines of the cage type.

Photo : different transmission lines for shortwave antennas leaving the transmitter building.


Photo: different transmission lines of shortwave antennas


Photo: different transmission lines of shortwave antennas


Photo: different transmission lines of shortwave antennas


Photo: different transmission lines of shortwave antennas

8. Transmitter room

A huge corridor, from end to end of the building, houses the shortwave transmitters. There are six in total, where only two of them are currently operational, in the frequency 11,780 kHz and 6,180 kHz.

All transmitters are of Brown Boveri and Cie and of Swiss origin.

The engineer Ismar Do Vale Junior, interrupts the transmission for a few seconds and opened the doors of these true monsters. Thanks to this cut in transmission, I was able to see them from inside, otherwise it would have been impossible, because of the high level of RF radiation from them.

Once inside the transmitters we could see the heart of these beasts, their powerful valves and power modulators that are cooled by a complex water cooling system. They are located on the second floor of the building, near the return hot water tanks, which allows them to have a useful life of approximately 40,000 Hs.

Videos by Mark Van Marx (Marcos Melzi):

Photos by Mark Van Marx (Marcos Melzi)


Photo: The engineer Ismar Do Vale Junior, opens the doors of the TX-01 the imposing shortwave transmitter from Brown Boveri and Cie, of frequency range 11,780 kHz


Photo: Open door of the imposing Brown Boveri and Cie shortwave transmitter


Photo: Image of the shortwave transmitter, Brown Boveri and Cie brand.


Photo: Martin Butera, next to the main shortwave transmitter from Brown Boveri and Cie


Photo: Image of the shortwave transmitter control panel of Brown Boveri and Cie brand.


Photo: TX-02 the imposing Brown Boveri and Cie shortwave transmitter, with a frequency range of 6,180 Khz.


Photo: Martin Butera, next to the powerful valves of the main shortwave transmitter of Brown Boveri and Cie brand.


Photo: Close-up image of the powerful shortwave valves from Brown Boveri and Cie.


Photo: Close-up image 2 of the powerful shortwave valves of Brown Boveri and Cie transmitter.


Photo: Martin Butera in the EBC truck, which were used to tour the site. The reader may have an idea of the immensity of the facility in the countryside.

9. Transmission monitoring and control room

The first thing we visited when entering the site, is the Hall of monitoring and transmission control room, this room houses a huge console where one can monitor the status of transmissions (power parameters and SWR)

There is also a spectacular switching console that allows you to connect any of the two transmitters with any of the antennas with the press of a button. Behind this console one can see different maps with the radiating lobes of the antennas, and the theoretical coverage of emissions from different areas of Brazil and the world.

These two consoles that control the parameters of transmitters and antenna switches are huge and as one can see they are a bit old, but nothing prevents their perfect performance, thanks to the technical maintenance of its dedicated personnel who maintain all the equipment correctly.
One can also see a huge rack with audio processors, modulators and satellite links for the programmes, which arrive from the studios located in Brasilia DF.

Videos by Mark Van Marx

Photos by Mark Van Marx (Marcos Melzi)


Photo: Power parameters console and SWR (75 Kw)


Photo: Power parameters console and SWR (75 Kw)


Photo: behind this console one can see different maps with the radiating lobes of the antennas, and the theoretical coverage of emissions from different areas of Brazil and the world.


Photo: Switching console that allows connection to any of the two transmitters with any of the antennas with the press of a button.


Photo: Martin Butera and the engineer Ismar Do Vale Junior next to the huge rack with audio processors, modulators and satellite links for programmes, which arrive from the studios located in Brasilia DF.

10. Electrical part

The entire park of “Parque Rodeador” antennas, always had its own electric power station, in March 2017, a strong thunder strike caused power outages and part of its own electric station was burned, that kept it out of the air for a long time (the shortwave service in 25 meters at 11,780 kHz and in 49 meters at 6,180 kHz as well as medium waves).

This problem led to installation of a large electric generator that feeds some of the power to the facility daily. Fuel is replenished daily to keep it operational.

While writing this report in July 2019, I could already visit the new electrical substation that was under construction, at the facility, to be equipped with the most modern technology.

The accident totally altered the routine and lifestyle of thousands of people living in the Amazon. Even the listeners had begun to develop a plan to raise funds to help repair all the damaged equipment.

Photos by Mark Van Marx (Marcos Melzi)

Photo: electric generator, with the ability to power the entire facility.


Photo: another view of the electric generator, with the ability to feed the entire property


Photo: EBC truck, ready to supply the electric generator.

Two kilometers from the centre of the facility, I saw the new under construction captive electrical substation with the most modern technology.


Photo: Watch out for a lot of high voltage


Photo: Martín Butera, next to the equipment of the brand new electrical substation.


Photo: Orlando Perez Filho “PT2OP”, former Executive Director of LABRE DF (League of Brazilian Lovers of Rádio Emissão), engineer Ismar Do Vale Junior, engineer Manoel Caetano dos Santos and Martín Butera, together at the new under construction electrical substation.

11. Transmitter power supply panel

In the following photographs taken by Mark Van Marx, one can see the power supply part of the transmitters of the Rádio Nacional da Amazônia. There is also image of a large transformer that powers all the equipment.

Video by Mark Van Marx (Marcos Melzi)

Photos by Mark Van Marx (Marcos Melzi)


Foto: Power panel


Photo: Entrance to the electrical power supply facility of transmitters


Photo: Martín Butera, playing with the RF. Please do not do this at home!

12. Rádio Nacional Brasília 980 kHz AM

Two kilometers away, the medium wave transmitter (OM) building is located within the short-wave antenna park.

The transmitter room is very similar to that of shortwave transmitter rooms. There are racks with satellite link receivers, audio processors and audio modulators of the signal that arrives from the studios situated in the capital. The signals are mixed before passing through the transmitter.

Also, apart from the Brown Boveri transmitters of 300 kW maximum power, for the medium wave (OM) signal, a modern transmitter from the famous American company Harris Broadcast is now being used, with an average power of 230 kW.

The transmitter of the National Radio AM of Brasilia works only during the night, when the signal is transmitted throughout the country. During the day, the Brasilia AM National Radio signal is transmitted from the SIA Transmitter Park, covering only the Federal District and its surroundings. This is due to the difficulty of transmitting a medium-wave signal throughout Brazil during the day.

The antenna, a monopole for the frequency of 980 KHz, has a height of 120 meters. Unlike the triangular towers that are normally found in this type of radios, it has a square shape and each side measures 1.20 m. This configuration makes the tower a really very robust structure.
Another interesting detail is that at the base of the tower there are 180 pieces of buried copper radials spaced at 360 degrees around the tower which form the ground plane of the antenna.

Photos by Mark Van Marx


Photo: Martín Butera, in front of the plaque that commemorates the foundation of the AM transmission building of the National Radio Brasília on 980 kHz AM.


Photo: Martín Butera, standing next to the Harris brand AM Broadcast transmitter.


Photo: Harris brand AM Broadcast transmitter safety notice.


Photo: Martín Butera, Engineer Ismar Do Vale Junior, Orlando Perez Filho “PT2OP”, former Executive Director of LABRE DF (League of Brazilian Lovers of Rádio Emissão) and Engineer Manoel Caetano dos Santos, together at the 120 Mts high tower, of National Radio Brasília on 980 kHz AM.

13. Final notes by Martin Butera

Personally, it was a pleasant surprise for me to find such an imposing infrastructure in South America, along with the super technology studios of the highest level, giant antenna fields, all this being managed by a responsible company like the EBC, which understands the importance of investment and professionalism as regards to Brazilian public communication.
I believe that Brazilian society needs to continue its efforts in discovering the indigenous peoples. The role of the Rádio Nacional da Amazônia is very essential in that task.

14. Acknowledgments by Martín Butera

I want to thank all those who supported me and collaborated to make this report, to my team of photographer and videographer – Ligia Katze (dear wife) and Mark Van Marx (friend of the soul).

Anne Evers and Luciano Maia Luciano G. Maia (Coordination of Public and Financial Relations
Executive Communication of Comunicação -Diretoria Geral EBC – Empresa Brasil de Comunicação.

To the producers of the National Radio da Amazônia, Luciana Couto, Taiana Borges and Solimar Luz.

To the broadcaster of the National Radio of the Amazon, Beth Begonha.

To the engineers Ismar Do Vale Junior and engineer Manoel Caetano dos Santos.

To Orlando Perez Filho “PT2OP”, former Executive Director of LABRE DF (League of Brazilian Lovers of Rádio Emissão), for honoring us with his accompaniment to the antenna field.

To my editor in chief, dear Chrissy Brand, for giving me the opportunity to work in South America, as a journalist for the BDXC. Chrissy brand is European DX Council Secretary-General – BDXC Communication (http://bdxc.org.uk/).

To the dear friend and listener from India, Sudipta Ghose (VU2UT) for his adaptation to English and correction, member of the Indian DX club International (www.idxci.in).

To my friend Ivan Dias da Silva Júnior, director of the Regional DX – Sorocaba-Sao Paulo- Brazil, who collaborates in the Portuguese translations and publishes this material in the form of a micro book, for the club he directs (https://ivandias.wordpress.com/).

To my friend, the Argentine radio listener Daniel Camporini, for writing a special prologue for this report (included in the Spanish version).

Finally my friend Thomas Witherspoon, director the SWLing Post, for publishing this report and collaborating in this way to the world of radio listening.

15. Review with information from the authors of this report

About the author

Martin is an Amateur Radio operator with more than 29 years of experience, and has participated in DXpeditions throughout South America, with the Argentine radio callsign LU9EFO and Brazilian callsign PT2ZDX.

Martin collaborates and writes for the British Dx Club newsletter.

Martín is the founder of the Brazilian CREW Radio Listeners’, called 15 point 61 (15.61). Martin is Argentinian, born in the city of Buenos Aires capital. He currently lives in Brasilia DF, capital of Brazil.

Martín Butera is a journalist, documentary maker and founding member of Radio Atomika 106.1 MHz (Buenos Aires, Argentina) www.radioatomika.com.ar

Foto: Mark Van Marx (Marcos Melzi)

Photographer. Photography teacher, Travel and Culture photographer. Independent photojournalist, AFP agency collaborator, Nikon Ambassador, Member of Getty Images Support Media.

He is an enthusiastic shortwave listener since 1997. Free band Radio operator who takes part in DXpeditions since 1998. A licensed amateur radio operator of Argentino LU3DU (extra class).

Foto: Lígia Katze

The journalist educated at the UCB (Universidade Católica de Brasília), a professional photographer at Canon College Brasilia DF, Ligia is the wife of Martín Butera and accompanies her husband on his radio travels around the world.


About the The British DX Club

Martin Butera is a contributing journalist for “Communication” magazine of the prestigious The British DX Club. We congratulate Martín Butera for this interesting report.
If you would like to be a member of the Briitish DX Club, you can find information here http://bdxc.org.uk/apply.html

Report made, and visit to Rádio Nacional da Amazônia in March 2019 (in radio studios), June 2019 (in antenna field), report completed and published in SWLing Post on October 20, 2019.

Please contact Martin at the following email address: martin_butera@yahoo.com.ar


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Guest Post: Decoding WEFAX using an RSP SDR and SDRuno

Many thanks to SLWing Post contributor, Mike Ladd with SDRplay, who shares the following guest post:


Basics to decoding WEFAX using an RSP and SDRuno

by Mike Ladd

SDR I use:
RSPduo from SDRplay using the Hi-Z input. Any model RSP’s can tune WEFAX transmissions. https://www.sdrplay.com/rspduo/

Antenna I use: Megaloop FX from Bonito. In an Inverted delta loop configuration pointed N/E-S/W. Any good antenna placed outdoors should be fine. It’s all about the SNR, not your S-meter reading. https://www.bonito.net/hamradio/en/mega-loop-fx/

Software:

SDRuno v1.32
SDRuno is an advanced Software Defined Radio application platform which is optimized for use with SDRplay’s range of Radio Spectrum Processing receivers.
https://www.sdrplay.com/downloads/

VBcable (donationware) vPack43
Transfers audio, digitally from one application (SDRuno) to another (Black Cat HF weather Fax) with zero loss.
https://www.vb-audio.com/Cable/

VAC (paid for use) v4.60
Transfers audio, digitally from one application (SDRuno) to another (Black Cat HF weather Fax) with zero loss.
https://vac.muzychenko.net/en/
https://www.sdrplay.com/docs/SDRuno_VAC.pdf

Black Cat HF Weather Fax (paid for use) beta 19
Decodes and produces images from the WEFAX transmissions from the output of SDRuno using a virtual audio cable.

Use the discount link available here
http://blackcatsystems.com/register/black_cat_hf_weather_fax_sdrplay_promo.html
https://www.blackcatsystems.com/software/hf_weather_fax.html

Black Cat Uno UDP
UnoUDP allows you control SDRuno’s VFO frequency from within Black Cat HF Weather Fax scheduler. This is done over a virtual com port pair using a virtual com port emulator. http://blackcatsystems.com/download/UnoUDP.zip

VSPE or COM0COM
VSPE is a paid for use app. COM0COM is completely free. Either one of these applications will work. A virtual com port emulator allows you to create a virtual com port. The pair will internally link Black Cat Weather Fax decoder to SDRuno’s using UnoUDP as the transport protocol.

VSPE http://www.eterlogic.com/Products.VSPE.html
https://www.sdrplay.com/docs/SDRuno_VSPE.pdf

COM0COM http://com0com.sourceforge.net/
https://youtu.be/dZg7puQ9Ajk

Introduction:

(some text taken and edited from various website)

This document is not a definitive guide to the WEFAX protocol, the process of decoding WEFAX images or reading a synoptic weather chart https://youtu.be/kzfNSvQREu8. This is only a collection of information that I have found scatter throughout the internet and re-compiled into a document, this document. Expect typographical mistakes, inaccuracies, or omissions.

WEFAX is an analog mode for transmitting monochrome images. It was the predecessor to slow-scan television (SSTV). Prior to the advent of the commercial telephone line “fax” machine, it was known, more traditionally, by the term “radio facsimile”.

Facsimile machines were used in the 1950s to transmit weather charts across the United States via land-lines first and then internationally via HF radio. Radio transmission of weather charts provides an enormous amount of flexibility to marine and aviation users for they now have the latest weather information and forecasts at their fingertips to use in the planning of voyages.

Radio fax relies on facsimile technology where printed information is scanned line by line and encoded into an electrical signal which can then be transmitted via physical line or radio waves to remote locations. Since the amount of information transmitted per unit time is directly proportional to the bandwidth available, then the speed at which a weather chart can be transmitted will vary depending on the quality of the media used for the transmission.

Radio fax data is available from the web on sites such as the ones hosted by the National Oceanic and Atmospheric Administration (NOAA). https://tgftp.nws.noaa.gov/fax/marine.shtml Radio fax transmissions are also broadcasted by NOAA from multiple sites in the country at regular daily schedules https://www.nws.noaa.gov/os/marine/rfax.pdf. Radio weather fax transmissions are particularly useful to shipping, where there are limited facilities for accessing the Internet.

Black Cat HF Weather Fax is a program that decodes WEFAX (Weatherfax, HF-FAX, Radiofax, and Weather Facsimile) transmissions sent from fixed locations around the globe.

A fax is transmitted line by line, typically at a rate of 120 lines per minute, or half a second per line. For example, to send a weather chart, you would start in the upper left corner. You would send the value of that pixel (dot), black, white, or perhaps a shade of gray. Then you would move over one pixel to the right, and send that pixel, and so on, until you reach the edge of the chart. Then you’d move all the way back to the left edge, and move down slightly, one line, and repeat the process.

Each pixel is converted into a certain audio frequency or tone. By convention, a tone of 1500 Hz represents black, 2300 Hz represents white, and frequencies in-between represent shades of gray. So if you listen to a fax transmission, you’ll hear the different tones as each pixel is present. For example, listen to a chart with mostly white background being sent. You’ll hear mostly the high pitch 2300 Hz, and some lower (1500 Hz) blips as each black pixel is sent. When a horizontal line is sent, you’ll hear a long half second burst of 1500 Hz, since the line is all black.

The transmitting station frequency modulates the carrier. That is, when a black pixel is transmitted, the carrier shifts down 400 Hz. When a white pixel is transmitted, the carrier shifts up 400 Hz. For a medium gray pixel, it stays on the assigned frequency. This is how most fax transmissions are made. Since we’re tuning it in SSB, it sounds to us as if the station is transmitting a variable frequency audio tone. The two processes are identical. This accounts for the confusion regarding what frequency to tune the radio to in order to properly decode the fax transmission. Different stations list their frequency in different ways. It is important to remember that a black pixel produces a 1500 Hz tone, and a white pixel produces a 2300 Hz tone within the AUX SP.

The setup works as follows. SDRuno demodulates the received signal. The demodulated audio is piped from SDRuno using virtual audio cable and sends it to the HF weather fax decoder. HF weather fax decoder receives this audio from the virtual audio cable that was demodulated from SDRuno and processes it, producing a picture on the screen

HF weather fax decoder can also set the VFO (tune) frequency of the RSP in SDRuno. This is done over the virtual com port pair using the UnoUDP application as the transport.

SDRuno can internally emulate a Kenwood TS-480, UnoUDP sends the Kenwood TS-480 serial commands via UDP over the virtual com port pair in order to set the frequency selected from the HF Weather Fax Scheduler option over to SDRuno.

You will need to install and configure the following applications.

1: A virtual audio cable.

2: A virtual com port emulator (If you would like HF Weather fax to communicate with SDRuno).

3: UnoUDP (If you would like HF Weather fax to communicate with SDRuno using the virtual serial emulator).

4: HF Weather Fax.

5: A simple wire antenna placed outdoors.

Virtual Audio Cable:

A virtual audio cable allows you to pipe the audio from one application (SDRuno) into another application (a decoder like HF Weather Fax) digitally. I will assume SDRuno is already installed with your device attached and functioning properly.

You can now download a virtual audio cable package.  If you already have a virtual audio cable package installed, you can skip to the next section. If you don’t have a virtual audio cable application installed, you only need to choose one and install only one of the two that are available.

Close any running apps, install the virtual audio cable and reboot your computer. When your computer boots to your desktop, your computer will now have a virtual audio cable pair installed on the system.

You can verify it the installation by going to your Control Panel and double clicking the Sound icon. VB-Cable and Virtual Audio Cable will only install a single virtual audio cable pair, one is for the input (Recording) and one is for the output (Playback). A single pair is all that is needed (as shown below).

Virtual Serial Port:

A virtual com port emulator is only needed if you would like Black Cat HF Fax decoder the ability to tune the station in SDRuno when you double click a station name in the HF Fax Decoder scheduler.

Please use the links provided (additional PDF’s and YouTube videos) on Page 2 of this document for an installation / configuration walkthrough.

You can download my WEFAX frequency bank for use in SDRuno below should you choose not to use a virtual com port emulator. https://signalsacrossthepond.com/download/mike-kd2kog-sdrplay-complete/

Download Black Cat HF Weather Fax and UnoUDP:

Download the latest HF Weather Fax beta package and the UnoUDP application from the link provided on Page 2 of this document. I suggest making one main folder called HFfax and two subfolders within HFfax for each of the applications. One folder is for the HF Weather Fax Decoder and the other folder is for the UNO UDP transport application.

Double click the HF Weather Fax beta ZIP file you downloaded and extract the full contents of this ZIP into the folder you created on your local drive. Right click the “Black Cat Weather Fax” EXE file and send a shortcut to your Desktop.

Double click the UnoUDP zip file you downloaded and extract the full contents of this ZIP into the folder you created on your local drive. Right click the “UnoUDP” EXE file and send a shortcut to your Desktop.

You should have two shortcuts on your desktop, One for the decoder and one for the transport app.

Black Cat UnoUDP:

HF Weather Fax needs a way to communicate with SDRuno, this is done via UnoUDP and the virtual com port emulator.

Launch UnoUDP with the above configuration. Set your UDP Receive port to 58084 and your UDP send port to 58083. UnoUDP must be left running in the background, this will control SDRuno. You can minimize the application or right click the shortcut and have UnoUDP auto minizine on launch.

You should see a Firewall popup prompt asking permission to allow UnoUDP to pass data within the system. You must allow this traffic to pass or external control of SDRuno will not be possible from the HF Weather Fax decoder scheduler.

Assign 1 of the 2 com ports from the virtual com port emulator to UnoUDP (the 2nd com port will be assigned to SDRuno).  My com port pair is Com 1 and Com 2, SDRuno uses Com1 and UnoUDP uses Com 2.

Black Cat HF Weather Fax:

HF Weather Fax needs to be configured in order to communicate with UnoUDP, this is done via the UDP settings. Click “Edit” and “Preferences” Set the UDP Send port to 58084 and the UDP Receive port to 58083.

You should see a Firewall popup prompt asking permission for HF Weather Fax to pass data within your system. You must allow UDP traffic to pass or external control of SDRuno will not be possible from the HF Weather Fax decoder scheduler.

SDRuno:

SDRuno needs its Output assigned to the Virtual Audio Cable. The output can be changed via the RX CONTROL panel, clicking the SETT. button on the top left and clicking the OUT tab.

SDRuno needs a com port assigned so it can be externally controlled. The serial port is assigned via the RX CONTROL panel, clicking the SETT. button on the top left and clicking the CAT tab.

I recommend running the RSP in LOW-IF mode, this is selected via the MAIN panel. This reduces the need to track separation between the Tuned frequency and LO (local oscillator) https://youtu.be/Fsns4P3JxrM

LOW-IF mode also minizines the LO being placed outside of the desired preselect filter of the device in use, Remember the preselect filter is automatically enabled based on the LO frequency https://youtu.be/w-vkiVp7Q4E

I also recommend leaving the IF AGC enabled and placing the RF GAIN as high as possible without causing an ADC OVERLOAD warning within the MAIN panel. If an ADC OVERLOAD warning appears, back the RF GAIN down.

https://www.sdrplay.com/wp-content/uploads/2018/06/Gain_and_AGC_in_SDRuno.pdf

Your first WEFAX decode (Using UnoUDP)

Launch UnoUDP and minimize it.

Launch Black Cat HF Weather FAX.

Launch SDRuno. Set the mode to USB and the filter width to 2.8k
HF weather fax will not set the mode or filter width at this time.

Click the Sked button in Black Systems HF Weather Fax. A current WEFAX transmission schedule will appear. Stations listed in White are either scheduled to transmit or about to transmit based on your computers clock. Stations show in Grey at the bottom of the list are currently off the air or not transmitting.

In the Freq Offset: box enter -1.9 and hit enter (Reason for this is on Page 5).

Click any of the stations listed in the Fax Transmission Schedule and it will automatically tune SDRuno to the correct frequency.

Black Cat HF Weather Fax folder will have a file named “Black Cat HF Weather Fax Docs” Please view this file to understand some of the advanced features available.

Your first decode (Without UnoUDP)

Launch Black Cat HF Weather FAX.

Launch SDRuno.

Navigate to the Memory Panel (MAIN panel and click the MEM PAN button)

Right click the Memory panel and select “Open bank”. Navigate you C drive telling SDRuno the location of WEFAX.s1b

Double click any of the frequencies shown within the WEFAX bank and SDRuno will set the correct mode and tune that station.  My WEFAX.s1b file defaults to the Hi-Z port. If your device lacks a HI-Z input, navigate to the port section within the memory panel, double click the stations port you want to edit and change it to the correct port that’s available or in use for your device. Right click the memory panel and “Save bank” to save the changes.

To use my SDRuno WEFAX frequency bank properly. The MCTR button must be enabled within the RX CONTROL panel, enabling this option allows you to double click and tune a station that is stored within the WEFAX bank. Make sure the LO is not locked in the MAIN panel (LO LOCK).

If a decoded WEFAX image looks blocky or skewed or possibly pixeled, I recommend that the lock output fractional resampler option is enabled in SDRuno. You can enable this from the RX CONTROL panel, clicking the SETT. button on the top left and clicking the OUT tab.

I hope this document helped guide you in getting started with decoding WEFAX transmissions from around the world. I am sure I missed some key features, remember this is only a primer/basics to decoding WEFAX. I do have an accompanying video located here

https://youtu.be/vAYGVimzNX8

Warmest of 73,
Mike-KD2KOG

Disclaimers

SDRPlay modules use a Mirics chipset and software. The information supplied hereunder is provided to you by SDRPlay under license from Mirics. Mirics hereby grants you a perpetual, worldwide, royalty free license to use the information herein for the purpose of designing software that utilizes SDRPlay modules, under the following conditions:

There are no express or implied copyright licenses granted hereunder to design or fabricate any integrated circuits or integrated circuits based on the information in this document. Mirics reserves the right to make changes without further notice to any of its products. Mirics makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Mirics assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Typical parameters that may be provided in Mirics data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters must be validated for each customer application by the buyer’s technical experts. SDRPlay and Mirics products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Mirics product could create a situation where personal injury or death may occur. Should Buyer purchase or use SDRPlay or Mirics products for any such unintended or unauthorized application, Buyer shall indemnify and hold both SDRPlay and Mirics and their officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that either SDRPlay or Mirics were negligent regarding the design or manufacture of the part. Mirics FlexiRFTM, Mirics FlexiTVTM and MiricsTM are trademarks of Mirics .

SDRPlay is the trading name of SDRPlay Limited a company registered in England # 09035244.

Mirics is the trading name of Mirics Limited a company registered in England # 05046393


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Mike’s tips for decoding SW Radiogram broadcasts

Many thanks to SWLing Post contributor, Mike (KA3JJZ), who writes:

Have you ever heard of the SW Radiogram digital broadcasts? These are produced by Dr. Kim Andrew Elliott and started way back when as the VoA Radiogram. They are now carried on 2 other stations (WRMI and WINB) on a schedule (check every week for a summary of images) that you can find on the SW Radiogram website;

https://swradiogram.net/

These tests consist of both text and images. Currently MFSK32 and 64 have been used, and an occasional ‘secret’ mode has been slipped in at the end of the transmission. The last time this was done, the mode was PSK125R.

You might ask how you can receive these broadcasts, and what you need to decode them. We have 2 wiki articles that go into great detail – one for PCs, and one for Android devices – here;

https://wiki.radioreference.com/index.php/Decoding_the_SW_Radiogram_Broadcasts

https://wiki.radioreference.com/index.php/Decoding_the_SW_Radiogram_Broadcasts_with_TIVAR

Yes, you can copy these broadcasts using an Android powered phone or tablet using an application called TIVAR. John VK2ETA has written a quick start guide which is available on the SourceForge website as well as the RadioReference wiki (the links are provided in the article)

These articles are written for folks who are just getting their feet wet, so the above articles touch on radios (no, you don’t need to use an expensive radio, though many do), antennas, propagation and more. The most popular software is FLDigi, but if you happen to have MultiPSK or DM780 (part of Ham Radio Deluxe), they can be used as well. Links are given for the software and any available support.

Along with Tumblr, SW Radiogram has both a Facebook and Twitter page (where members often post decoded images) here…

https://www.facebook.com/groups/567099476753304/

https://twitter.com/swradiogram

Thank you, Mike! Yes, I’m a big fan of the SW Radiogram–the community that has formed around this particular shortwave program is quite amazing. Thanks for all of the tips!

Click here to view the SW Radiogram website.

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Paul’s report from the UK’s National Hamfest

Many thanks to SWLing Post contributor, Paul W4/VP9KF, who shares the following report from the UK’s National Hamfest:


Your travelling foreign correspondent took in a visit to the UK’s National Hamfest held in Newark, Notts.

We arrived right on opening time (10am) and were the first in the door.

There was a ‘rush’ to the SDRPlay stand because they were giving away some nice FLASH drives to the first 25 people to get there. The author managed to get one and later found it was a) fast b) pre-loaded with software for all things SDRPlay. They were busy showing the new diversity software amongst other things.

bhi had some new hardware and I took the chance to thank them for a prize won in the W5KUB Xenia draws.

The hall was pretty empty (this was the second day and a Saturday). Noticeable was that some products were already sold out and on back order [such as the amazing nanoVNA].

It’s a shadow of the former Leicester Show which was the precursor to this event with a lot less parts on sale.

I had a long chat with Eric of Elecraft while twiddling with the K4 and suggested some improvements to the button usage, which he said would be tested in use. A date of the ‘beginning of the year’ for first shipments was mentioned and that the first batch would be ‘large’ [much more than 100] followed by smaller batches. Components are on order, some of which are on long lead times (and have to arrive in good shape for surface mount assembly down the line).

The K4 was ‘playing’ the 7 Area QSO Party on several bands and most controls were operable. This was streaming from an IQ recording and an RF modulator straight into the rig. Just exactly how close this was ‘to the original sound’ and TRUE performance of the rig and/or software is
to be seen.

The weather was fine for the show (although patchy – XYLs reported that it poured with rain back in Nottingham itself!). Turnout was very disappointing and a lot of grey hair was to be seen in the one (yes one) Hall Building.

73,

Paul W4/VP9KF [and G4BKI]


Thank you so much for the report, Paul. I do want to make a pilgrimage to the UK’s National Hamfest one year–any excuse to visit my home-away-from-home country! 

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Guest Post: Paolo’s Tips For Avoiding Internet Scams

Many thanks to SWLing Post contributor, Paolo Viappiani (SWL I1-11437), who shares the following guest post:


Some Tips For Avoiding Internet Scams

by Paolo Viappiani – SWL I1-11437

pviappiani@tin.it

Recently, I have been amazed by the growing number of frauds that foul up the radio market on the Internet (I was scammed too), so I decided to write a post in order to help anyone who is interested in buying anything on the web.

First, it’s worth saying that most scam attempts involve high-quality items that are offered at surprisingly low prices. One of the most significant examples involves some rare (and discontinued) high-end radios by National Panasonic, typically the RF-8000 and RF-9000 models. In this post, I make an example of the RF-8000, but scams also concern radios of other brands..

Generally speaking, a number of advertisements on the most known advertising/classifieds sites (Quoka.de and ebay-kleinanzeigen.de in Germany, Subito.it, Kijiji and AAAnnunci.it in Italy, Le Bon Coin in France, ComoFicho in Spain, etc.) are mirrors for larks only, and we have to pay a great attention in order not to be scammed.

But… how can we recognize a scam?

The most common scams use the following techniques:

  1. The scammer advertises a very rare radio in like-new condition at an unbelievably low price. The buyer does not want to miss the bargain, so he contacts the seller and promptly transfers the money to him without further ado, but after that he waits in vain for the delivery of his item.
  2. High quality radios offered very cheap. If you contact the seller, the item is suddenly abroad. The alleged seller then proposes to handle the purchase through a “trust company”. The radio should be paid for in advance and the amount sent via cash transfer, but after that you never hear anything from the seller again.
  3. Alternatively, the buyer is requested to to deposit the money to the eBay company account to get the product. But the account is fake (really eBay has no “COMPANY ACCOUNT” and never handles private transactions–!), so the buyer loses his money and receives nothing in return.

Please also notice that often the fraudulent sellers offer a free period for evaluating the item, saying that  if you do not like the device, you can send it back. Please don’t fall into this trap, it is only one of the means the scammers use to entice you to purchase, but it is not true at all!

In the following section I’ll recount some examples of real scams concerning the National Panasonic RF-8000 and RF-9000 radios (but, as I already mentioned, the scams involve many other radios and also high-quality electronic or electro-acoustic devices).

One of the most prevalent (and very dangerous) scams concerning the RF-8000 radio is (was) perpetrated by a Portuguese seller who offered (for about 2.300 Euro on the AAAnnunci.it and Quoka.de websites) a very nice appearing radio, look at the photos below.

Really a radio in like-new conditions, uh?

But it is just a trap: most of the Panasonic RF-8000 radios have the leather covers on all sides cracked like crocodile skin (look at the image below); only a very few units still have the covers in pristine condition and for sure they cannot be found at cheap prices!

Incidentally, all the pictures used by that scammer (including the two shown in the first two pictures above) were stolen from an old eBay advertisement of October 2018 and that wonderful appearing RF-8000 was sold to a radio collector in China for about $ 5,000 USD.

But the same images also recently appeared on some European advertisement websites (in Italy and in Germany too); if you ask for info, you’ll be contacted soon by a seller from Portugal who offers to handle the purchase through a “trust company” of his confidence, named TrafCargo (beware of this, it is a convincing but fake website!).

Then, the seller requests that the amount for the radio and its shipping costs be sent via a bank wire transfer to the fake transportation company.

After that you never hear anything from the seller again.

Very similar scams are also found in various advertisement/classified websites (Quoka.de, ComoFicho.com etc.), look at the images below as examples. If such items are offered cheap, it is for sure a scam:

A similar attempt of fraud is commonly perpetrated by other people, including a female seller from Spain. As you might suspect, she offers something that looks like a real bargain, but it’s only a scam. After you have asked for info on the product, you receive a message in which it is specified that the item is located abroad and you are asked to deposit money to a fake “eBay” account (note that eBay does not accept any payment outside their site!).

In order to be more persuasive, often the scammer attaches a copy of his/her passport of other identity documentation in order to appear as a serious seller–please do not trust them however!

Also, beware of the fake “eBay invoice” that sometimes the scammers send, and for anything that involves eBay, contact the eBay helpdesk, ask for specific info and report them the fraud eventually.

In the following section you’ll find some useful advice on recognizing scams and making secure and safe purchases on the Internet:

  1. Always beware whenever the item is in a place (or a country) different from the one that was specified in the advertisement; also there is a valid reason for suspicion when the name or the address of the advertiser does not match the seller’s ones;
  2. Do not completely trust the pictures sent by the seller (they could be stolen from the Internet) and don’t forget to proceed to a “Google Image” search in order to find the sources of similar ones;
  3. Always ask the seller for some specific pictures or videos (radio precisely tuned on various frequencies and/or modes) and do not accept any runarounds about it (“you can try the radio for some days”, etc.); normally the scammers do not have the items they offer at hand, so they are not able to satisfy your precise requests.
  4. Never pay for the item in advance by rechargeable cards like Western Union or other non-secure ways of payment. Also the Bank Transfer (Wire Transfer) is not a secure form of payment in order to avoid frauds;
  5. Always ask the seller for payment by PayPal “Goods and Services” (NOT “Send money to friends”). If you choose Goods and Services, your purchase will be fully covered by the PayPal warranty.

And, in the case that you are a victim of a scam anyway, please always report the incident to the Police or the Judiciary of your Country, and don’t forget to also warn the site where the announcement was found.

Following the above advice should be sufficient to avoid any scam. So, good luck on your future web purchases!


This is excellent advice, Paolo. Thank you for sharing your experience!

One of my favorite bits of advice above–and one I use anytime I make a significant purchase via a classifieds website–is to ask the seller for specific photos or a video of the item. As you say, they don’t typically have the item on hand, so can’t comply and will make up excuses. That’s a major red flag!

Another red flag? If it sounds too good to be true, it probably is! Trust your instincts and avoid the hassle and headache.

Post readers: Please share any other advice you have about avoiding radio scams. Have you ever been the victim of a scam? How did it play out? Please comment!


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Please consider supporting us via Patreon or our Coffee Fund!

Your support makes articles like this one possible. Thank you!

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Guest Post: Photo tour and history of the PPE Observatório Nacional time signal station

Many thanks to the SWLing Post contributor, Martin Butera, who shares the following guest post:

__________________________________________________________________________________________________

Visiting the most important time signal station in South America – PPE Observatório Nacional

by Martin Butera

Still photographs by: Mark Van Marx (Marcos Melzi)

Video by: Ligia Katze

English adaptation and correction by: Sudipto Ghose (VU2UT)

We invite you to a tour of the service division of the official time signal station of the National Observatory of Rio de Janeiro, Brazil PPE BRA OBSERVATORIO NACIONAL

Let us take you to a place for which all the readers should enjoy: the famous 10 MHz short wave transmitter of the Hour Service Division (DSHO), of the national observatory of Rio de Janeiro, Brazil.

We were invited by the engineer Mr. Ozenildo de Farias Dantas, in charge of the maintenance and flawless operation of the transmitter, to take a look at the famous transmitter.

The Hour Service Division (DSHO) broadcasts Brazil’s Official shortwave time signal on the frequency of 10 MHz.

The transmitter is located in the park, outside the main building, in a small, climate-controlled house specially designed to accommodat it.

Here are some of the transmitter’s technical notes:

Manufacturer: Redifon Telecommunications Limited, London SW.18, England
Model: HF TRANSMITTER REDIFON G453
Power: 1 kW
QRG: 10 MHz
Type of modulation: A3H
Type of antenna: horizontal dipole – ½ wavelength
QRA: PPE

Here are the geocentric coordinates of the site( WGS84):

X = 4283641.45 m Length = 43 13 27.5 W
Y = – 4026026.11 m Latitude = 22 53 44.6 S
Z = – 2466098.27 m Height = 37 m

The content of the transmission: the transmission consists of the official time of Brazil (= UTC – 3 hours) announced by a female voice that begins in Portuguese with the following phrase “National Observatory” followed by the current time (hh: mm: ss) every 10 s and with a short beep every second with a modulation of 1 kHz for 5 ms and a long beep with a modulation of 1 kHz for 200 ms at 58 °, 59 ° and 60 ° seconds. [Audio sample below.]

The Hour Service Division (DSHO) also broadcasts Brazil’s official time with 2 local VHF broadcasts for the city of Rio de Janeiro on the 166.53 MHz and 171.13 MHz frequencies.
The transmission of the time signal of 10 MHz by the DSHO began in November 2008, over all these years, this signal was already picked up by radio listeners in different parts of the world, and the reports are confirmed by QSLs. Dr. Ricardo Carvalho head of that division,

Dr. Ricardo Carvalho kindly gave me one such QSL.

Photos

Engineer Ozenildo de Farias Dantas and our journalist Martin Butera, entering the house of the shortwave transmitter.
Shortwave transmitter, Redifon Telecommunications Limited, used in the Service of the official Time of the National Observatory of Rio de Janeiro. There is a ubiquitous BIRD Wattmeter on top left of the transmitter.

From another angle, the short wave transmitter, Redifon Telecommunications Limited, used in the Service of the official Time of the National Observatory of Rio de Janeiro.
Engineer Ozenildo de Farias Dantas dismantles a part of the transmitter panel, to begin with his routine of calibration and maintenance of the transmitter.
The engineer Ozenildo de Farias Dantas and our journalist Martin Butera, along with the transmitter Redifon Telecommunications Limited.

The Antenna

It is a simple but robust dipole, perfectly cut and calibrated by engineer Ozenildo de Farias Dantas for the frequency of 10 MHz, which has given excellent results to this day.

One of the sections of the dipole is supported by the historic imperial tower of the observatory. This tower is famous because many years ago a balloon was inflated at the precise moment that it was 12 noon and was launched so that this was observed in the port of Rio de Janeiro that was called the famous “half astronomical day”.

Dipole wire antenna of the National Observatory
we can see a section of the dipole, supported by the old Observatory tower
Mr. Ricardo José Carvalho (head of the division), with a history book of the National Observatory of Rio de Janeiro, where he mentions about the first tower of the observatory. Behind we can see that the tower still remains intact. Old tower of the National Observatory
Here we can see that they have a tower with different antennas to receive different world time signals
Here we can see the antennas of the VHF transmitters

Listening to the time signal frequency stations is an interesting aspect of the DXing. Many may not know that these stations are in operation in different parts of the world, and have been since the early days of the radio to the present twenties.

The purpose of these stations is to cover various branches of science, such as seismology, meteorology, astronomy, geodesy, etc.

Between the different stations a constant effort is made to coordinate their time internationally so that in the future they can all maintain and supply a world time standard without the slightest difference.

Brazil has the most important time station on the South American continent, I am very happy to present this exclusive report for SWLing Post for all of you.

This was the first time a group of DXers has be welcomed by the Service Division of the Hour (DSHO), from the National Observatory of Rio de Janeiro.

I was especially welcomed by Mr. Ricardo Carvalho, Head of the division, who kindly guided us on an extensive tour, showing all the facilities. I was also able to film a pleasant interview (in Portuguese).

Click here to view on YouTube.

Surely all of you who are now reading this report know that listening to the short wave, can become the most instructive hobby that exists.

To know about a country, its customs, its culture, its gastronomy, its geography, to follow the national or international current affairs, are the interests that define the various aspects of the hobby of radio listening.

The main purpose of listening to international short wave radio stations is to know the world better, to open up to other cultures, to other ideologies, to demystify the unknown, to have access to the many facets that make up the world.

In short, the listening to international short wave radio stations of the whole world is traveling around the globe without leaving home or even getting up from the couch.

Station History

Current entrance of the National Observatory, museum of astronomy and related sciences of Rio de Janeiro.

National Observatory of Rio de Janeriro 1827 – 2019

Now, I shall try to summarize 192 years of history, a mission that is not at all simple.
To remain as a scientific institution of recognized competence for 192 years is an almost impossible mission in Latin America.

The National Observatory (ON), established in Rio de Janeiro, is an example of determination since its foundation on October 15, 1827 by Emperor Dom Pedro I.

Since then, much has changed at the National Observatory, where the creation of the Brazilian Official Time Division with its acronym (DSHO), established by law in 1913, stands out. Nowadays, the service is generated from a set of twelve atomic clocks that also contribute to the official world time scale.

The need for an Astronomical Observatory in Brazil began in the colonial period, its creation was necessary due to the increase in commercial activities and the rapid growth of ships arriving and departing from the ports of Rio de Janeiro since the beginning of the 19th century, and this demand became more evident.

For the sake of safer sea travel, it was essential to obtain accurate knowledge of the magnetic declination, the average time and information about the length so that commanders could regulate the timers.

That is why the installation of an observatory in a fixed location could offer ships more accurate information than those obtained at sea.

The first records date from the inception to establish an observatory in the Hill of the Castle in 1730 on the initiative of the Jesuits, in the same place was established in 1780 an observatory of Portuguese astronomers where they made the first observations of astronomy and meteorology.

Hill of the Castle in 1730 (File ON)

But only in October 1827, by decree of D. Pedro I (first emperor of Brazil), the headquarters of the Imperial Observatory of Rio de Janeiro was established, this was the first institution of this genre built in Brazil.

Initially, this astronomical observatory was established in the tower of the Military School, in charge of Pedro de Alcántara Bellegarde (military, educator, astronomer and Brazilian engineer), who played a fundamental role in the area of important scientific institutions throughout the 19th century.

However, until at least the 1870s, the activities of the institution were almost exclusively related to the instruction of military school students.

Only in 1871 were its functions redefined, when it came out of the military administration, the Observatory could dedicate itself mainly to research and service activities in meteorology, astronomy, geophysics, measurement of time.

Such redefining of its sphere of activity was driven by the Administrative Commission of the Imperial Observatory, which in this period began the process to choose the new site, in a place that is considered more appropriate, where it would be transferred later.

The conclusion of several studies culminated with his transfer to the hill of “San Januário”, at the beginning of the 20th century, where it still operates today.

Panoramic view of the domes of the meridian lunettes used for the determination of time. (File ON)
Building of the National Observatory built at the beginning of the 20th century, when it was moved to Morro de São Januário. (File ON)

These fundamental changes, that took place after 1871, happened during the administration of Emmanuel Liais (he was a politician, botanist, astronomer and French explorer who stayed in Brazil for many years), who was responsible for the process of remodeling the observatory, during the two terms for which he was the director (from January to July of 1871 and again between 1874 and 1881).

The increase in the activities of the Imperial Observatory led to the publication of the first volume of the Observatory Yearbook in 1885, which gave continuity to the Astronomical Ephemerides, published between 1853 and 1870.

The aim of the Yearbook was to disseminate information obtained from astronomical and meteorological observations, constituting until today an important bibliographical reference on the annual scientific production of the institution.

In 1886, the Observatory Magazine, the country’s first scientific journal, was published in 1886 with the aim of disseminating scientific productions, which lasted for only a short time and were stopped in 1891.

With the new political winds blowing from 1889, triggered by the proclamation of the Republic, also changed the orientation of the institution, subordinating itself to the Ministry of War and receiving the name of Observatory of Rio de Janeiro.

Only in 1909 it was renamed as OBSERVATORIO NACIONAL (ON): the Ministry of Agriculture and the Directorate of Meteorology and Astronomy was created, and the Observatory was made subordinate to this.

From then on, the institution began to provide the weather forecasts for different purposes. During that time, the activities of meteorology and astronomy walked together and the calculation of time was made by astronomical methods. These two functions, however, were separated in 1917, when the National Observatory only covered studies on astronomy, geophysics, and time and frequency. With this redefinition of functions, the scientific trajectory adopted by the institution throughout the 20th century was marked.

The beginning of the 20th century also gave rise to ideas that would lead to scientific moods. The accelerated process of urban reforms and the redefinition of the state function as a promoter of national scientific activity represented a new apparatus for the diffusion of sciences, accompanied by the notions of civilisation, modernity, reason and progress that drove all actions in the scientific field.

The institutional framework of the National Observatory, in relation to these intense transformations in the Brazilian social, political and scientific plan of the beginning of the century, was evidenced in the management of Henrique Morize (considered the great introducer of experimental physics in Brazil), having assumed the post of the Director of the Observatory in 1908, was responsible for several important modifications of the institution during this period, in which Rio de Janeiro also underwent intense urban reforms.

During the twentieth century, several reforms in the political-administrative spheres changed the jurisdiction of administration to which the institution was linked; however, they changed their attributions. In this sense, In 1930, the Observatory was brought under jurisdiction of the newly created Ministry of Education and Culture; in 1976, it was transferred to the control of the National Council for Scientific and Technological Development (CNPq). In 1999, such transfer of jurisdiction took place to the Ministry of Science and Technology which is maintained till today.

Einstein’s theory of relativity

The National Observatory of Rio de Janeiro, has always been present on the world stage with many scientific contributions which were internationally recognized.

Perhaps one of the most “famous” such contribution was in the year 1919, when the National Observatory coordinated the English expedition that observed the total eclipse of the Sun, in the Brazilian city of Sobral, in the state of Ceará.

The phenomenon was also observed parallelly in the Prince Island. Such observation contributed to the confirmation of Einstein’s theory of relativity, when the deviation suffered by the light of the stars in the background of the sky caused by the gravitational field was verified due to the mass of the Sun.

Visit of Albert Einstein to the National Observatory in 1925, after having tested his Theory of Relativity thanks to the work of the National Observatory of Rio de Janeiro. (File ON)

Importance of creating a specific division of time in Brazil

To understand the importance of creating a specific division of time (DSHO), within the National Observatory of Rio de Janeiro, we list below the very relevant fact about Brazil.

Brazil has a territory of continental dimensions with an area of 8,547,403 square kilometers.
The extension of the territory, we can analyse it in the following way from north to south and from east to west, in the first case, from Monte Caburaí (Roraima) to Arroio Chuí (Rio Grande do Sul) 4,395 kilometers are recorded, in the Serra da Contamana (Acre) to Ponta do Seixas (Paraíba) results in 4,320 kilometers. As you can see in the following graphic

It is the largest country in Latin America and the fifth largest in the world. If we put all the countries of Europe ( except the Russian – European part) and there would still be space left over in Brazil.

I took the trouble to scan an old Brazilian geography book since I found the following image and it seemed very interesting, this image leads to a good reflection on the dimension of Brazil.

In case it is not clear to the valued readers, the size of Brazil and its continental dimensions, the whole United Kingdom alone, fits within the state of São Paulo.

That is why, because of the enormous size of Brazil, it has landmass in three different hemispheres at the same time: the majority in the southern hemisphere, a small part in the northern hemisphere and all its territory in the western hemisphere.

In the North It is cut by the Line of Equator and in the South by the Tropic of Capricorn, thus getting 92% of its area in the tropical zone.

Another aspect of the geographical position of Brazil is its latitudes and longitudes, that is, its geographic coordinates, which are generally measured from the equator (latitudes) and from the Greenwich meridian (longitudes). Thus, in latitudinal terms, the Brazilian territory extends from something close to 5º North to approximately 33º South. In longitudinal terms, the extension extends from 35º West to a little less than 75º West. But if we ignore some of the oceanic islands in the Atlantic, they are placed in somewhat smaller lengths.

Due to its great east-west extension, Brazil presents a great variation of time zones, totaling four different regions that we can observe in the following map.

The first time zone is two hours behind the Greenwich Meridian (-2GMT, therefore) and covers only the islands in the Atlantic Ocean, (Yellow color on the map).

The second and most important portion (-3GMT) covers most of the Brazilian states, including the Federal District and the capital, Brasilia, making it the official time of the country, (orange).

The third area (-4GMT) covers some states to the west, namely: Mato Grosso, Mato Grosso do Sul, Rondônia, Roraima and most of the Amazon, (green).

The fourth and last time zone (-5GMT) covers a small western part of the Amazon and the state of Acre, (pink).

And if you still do not understand the complexity of the Brazilian time system, we can mention this curious fact: the first day of the year never reaches all the people of the world at the same time. In Brazil it is not different, because Brazilians can celebrate the New Year four times! This is due to the four time zones that we mentioned earlier.

Brief summary of the History of the Official Time Service Division (DSHO)

The beginning of the activities of the National Observatory precedes its creation date in 1827. Since 1730, regular observations of astronomy, meteorology and terrestrial magnetism have already been carried out in Morro del Castillo, in the city of Rio de Janeiro.

With the arrival of the royal family to Brazil in 1808, the heritage with the research of the time was transferred to the Royal Military Academy. Nineteen years later, Pedro I determined the creation of the entity that would inherit his patrimony.

Since then, National Observatory has accumulated a precious history that covers the areas of Astronomy, Geophysics and Metrology in Time and Frequency.

The time and frequency metrology is the responsibility of the Services Division of the Official Time, which for more than a century and a half has been legally responsible for generating, maintaining and disseminating the Official Time of Brazil and also plays the role of Time Laboratory and Primary Frequency, denominated in its initials as (LPTF).

The Official Time Service Division inaugurated its new facilities in 2004.

The modern building is named after Carlos Lacombe, in honor of the engineer who directed that division in the period from 1963 to 1977 and participated, along with Henrique Morize and Roquete Pinto, in the creation of the first radio station in Brazil, called (Rádio Sociedade do Rio de Janeiro).

Enter the building of the official Brazilian time, it is simply fascinating, it is very large and has the most modern technologies.

To understand better how it is inside, I decided arrange the tour in the following order: Museum, Generation room, Conservation and Dissemination of time, Laboratory and we will leave the Short Wave Transmitter for the last.

Come with me !!

Martin Butera at the entrance of the modern building of the Official Time Service of the National Observatory of Rio de Janeiro.

Small Museum

When entering the modern building of the Service of the hour (DSHO), of the national observatory, the first thing we can observe is a small but very interesting museum of the first clocks and measuring instruments, kindly Mr. Ricardo José Carvalho (head of the division ), he was detailing us one by one.

Click here to view on YouTube.

These pieces are fundamental to understand the process of evolution in the measurement of time.

Different old instruments for measuring the time used by the Official Time Hour Service (DSHO), from the National Observatory of Rio de Janeiro.
Different old instruments for measuring the time used by the Official Timekeeping Service (DSHO) of the National Observatory of Rio de Janeiro.

Among the pieces stand out different models of chronographs used in the mid-1950s, from the manufacturer Édouard Belin.

Édouard Belin, was an inventor and photographer born in France in the year 1876.
Chronographs were an instrument that measured time and maintained unity. In most analog models it was up to hundredths of a second, a chronometer at that time was a high precision certificate of a watch.

Another old chronograph
Another very interesting piece of the museum is the issuer of time signals from the manufacturer James Muirhead, famous British watchmaker.
We can also observe the first spoken recording system of the hour, it was a complex system of records made in Brazil.
In the same piece of furniture at the bottom of the piece mentioned in the previous photo, we can see a classic Collins Radio Company receiver, which was used in the mid-1950s to tune in to other world shortwave time signals.
Undoubtedly a very important piece is the first cesium clock, which began to work in Brazil in 1970, it is an HP5061A
Mr. Ricardo José Carvalho (Head of the Division) and our journalist Martin Butera, editor of this report, together in Brazil’s first atomic clock.

Room of Generation, Conservation and Dissemination of the time

Leaving behind the small museum, we continue with our tour with Ricardo José Carvalho (Head of the Division) and we are about to enter the room where the Generation, Conservation and Dissemination time racks are located.

Click here to view on YouTube.

Before, we progress further it is necessary to understand briefly what is meant by generation, conservation and dissemination of time.

What is meant by generation?

The generation of time and frequency, that is, the second atomic, is done in the Official Time Division of Brazil, by means of Cesium commercial clocks and hydrogen maser clocks.
The atomic time by the International System of Units (SI) in 1967 is defined as:
“The second is the duration of 9,192,631,770 periods corresponding to the transition between two hyperfine levels of the ground state of the cesium 133 atom radiation.”

What is meant by conservation?

The conservation of the “greatness of time and frequency”, is realised through the uninterrupted operation of the atomic clocks and their evaluation of stability by means of the measurements of time and frequency difference between the clocks.

What is meant by Dissemination?

The dissemination of the “greatness of time and frequency” is carried out by the calibration of atomic clocks, frequency counters, chronometers and other different equipment. These measurements are sent to the laboratory of the division where they are checked through other standard signals and by the official time synchronization network.

In the room where the Generation, Conservation and Dissemination time equipment racks are located, we can observe 11 racks in total, with different equipment such as generators and gong distributors, top, IRIG code, synchronism signals, NP generators, secondary clocks , temperature monitors, “no-break” phase monitors, electric power phase monitors, internet talk time monitor, ZAG 500 talk time monitor, various distributors and amplifiers, cesium registers, audio and GPS distributors (time transfer system) and much more.

In the following videos, Mr. Dr. Ricardo Carvalho, Head of that division explains and details the operation of several of these teams, we invite you to see the following video links (in Portuguese language).

Click here to view on YouTube.

Racks of equipment for Generation, Conservation and Dissemination of Time, Service of the Hour (DSHO), of the national observatory Rio de Janeiro Brazil.

Racks of equipment for Generation, Conservation and Dissemination of the time, of the Service of the official hour (DSHO), of the national observatory Rio de Janeiro Brazil.
Different views of the Racks of equipment for Generation, Conservation and Dissemination of the time, of the Service of the official time (DSHO), of the national observatory Rio de Janeiro Brazil.
Different views of the Racks of equipment for Generation, Conservation and Dissemination of time, of the Service of the hour (DSHO), of the national observatory Rio de Janeiro Brazil.
Different views of the Racks of equipment for Generation, Conservation and Dissemination of time, of the Service of the hour (DSHO), of the national observatory Rio de Janeiro Brazil.
we can observe equipment, such as the monitoring of “no-break” phases.
Technician working in the room of the Racks of equipment for Generation, Conservation and Dissemination of the time, of the Service of the official hour (DSHO), of the national observatory Rio de Janeiro Brazil.

Laboratory

After leaving the modern room of Generation, Conservation and Dissemination of the time, we enter into another important room – the laboratory.

https://youtu.be/OivtFjm7MRU

https://youtu.be/1Oj9jNzqbuw

https://youtu.be/WgS-DtDTr9c

https://youtu.be/DXgJ_CTT1Sw

Here we will find various equipment for measuring, calibrating and adjusting the time, up to a faraday cage. Also in the laboratory are jealously guarded famous atomic clocks.

Currently, the service of the official Brazilian time (DSHO), has 2 atomic clocks of the Symmetricon MHM hydrogen maser (valued at approximately 250 thousand dollars each), 12 cesium standard clocks (valued at approximately 80 thousand dollars each), they are 3 three HP 5071A clocks, 3 three Agilent 5071A clocks, 4 four Symmetricon 5071A clocks, 1 a CS4000 clock, 1 a Datum 4310A, 1 a rubidio HP5065A standard clock and two GPS / glonass / galileo-TTs-4 receivers.

Having a laboratory is essential to keep exactly calibrated the national standards of time and frequency, some of these parameters are the basis of the Brazilian Metrological Traceability of Time and Frequency.

At the international level, the traceability of national standards and Brazilian official time is established with the International Bureau of Poids and Mesures (BIPM), also with Brazilian official time is compared in real time through the Inter-American Metrology System (SIM) that it is accessed through GPS Common-View.

Faraday cage

Another surprise that we are not prepared to see was to get up close and to be able to enter a famous “Faraday cage”,

On one side of the laboratory there is a famous Faraday cage, which Dr. Ricardo Carvalho explains to us, it is a fundamental requirement for the measurement of atomic clocks, since no unknown entity can be present during the calibration process, we are talking about the calibration of atomic clocks costing 250 thousand dollars.

Faraday cage in use for calibration of the official Time of the National Observatory

Faraday’s cage was an experiment conducted by Michael Faraday to demonstrate that an electrified conductive surface has a zero electric field inside it, since the charges are distributed evenly on the outermost part of the conductive surface (which is easy to try the Law of Gauss), for example we can mention the Van de Graaff generator.

In Faraday’s experiment a metal cage was used, where an insulation and a wooden chair were placed on which Faraday sat, an electric shock was given to him and nothing happened to him, which shows that a body inside the Cage could remain there, isolated as the electrons are distributed on the outer surface of the surface.

Our special correspondents Mark Van Marx (photographer), Martin Butera (journalist) and Mr. Ricardo José Carvalho (head of the division), inside the Faraday cage, together with the calibration equipment of the atomic clocks.

Racks of diverse equipment of the laboratory, of the Service of the hour (DSHO), at the national observatory Rio de Janeiro Brazil.

Racks of diverse equipments of the laboratory, of the Service of the hour (DSHO), at the national observatory Rio de Janeiro Brazil.
Our photographer Mark Van Marx, taking photograph of the various equipments of the laboratory, of the Service of the hour (DSHO), at the national observatory Rio de Janeiro Brazil.
Different signal and frequency counters, used in the calibration of watches.

Next to the famous Clock Maser of Hidrogenio Symmetricon MHM

The most accurate watch of Brazil and also of South America, is located in the basement of the Time Service Division of the National Observatory in Rio de Janeiro, the clock is kept in a special room, with constant temperature and humidity, to be able to access to watch, you have to go through three sophisticated alarm controls, we had the honor of being able to access exclusively for the ‘DX Clube Sem Fronteiras’.

This watch comes from the United States. The approximate cost is US $ 250,000.
This atomic clock “Maser Symmetricon”, which is expected to delay or advance only one second in 10 million years runs using hydrogen.

A curious fact is that from the confirmation of the order for its acquisition, the clock took six months to manufacture. The process went through the Department of Defense of the US government. To obtain an authorization of export, since it is a device that generates time with high precision.

Our special correspondents Mark Van Marx (photographer), Martin Butera (journalist) and Mr. Ricardo José Carvalho (head of the division), together with the most accurate atomic clock in Brazil as well as in South America.

From Atomic clocks to Quantum Optics

The search for the most accurate clock is an extreme challenge. Brazil does not want to be left out and like the leading countries are using “Quantum Optics”.

If you think that everything ends up in the measurement of the time produced by the atomic clock, you are wrong, in the service of the national observatory, you are already having experiences of quantum measurements through the laser system.

In another sector of the division, there is a sophisticated optical frequency measurement device. It is obtained from a company named Menlo Systems.

Menlo Systems is a German company, founded in 2001 by Professor Hänsch, Dr. Ronald Holzwarth, Dr. Michael Mei and Alex Cable as a spin-off of the renowned Max-Planck Institute for Quantum Optics.

It is a revolutionary technique for measuring the frequency of light. This invention has been called “… the greatest advance in precision electromagnetic measurements since people started measuring frequencies”

The time division of the National Observatory of Rio de Janeiro has already begun to perform experiments with optical measurements of high precision in various applications such as optical clocks, cold atoms and molecules, metrology, distance measurements, Fourier spectroscopy and Lidar measurements.

They know that the world is increasingly ultra-precise and ultra-fast and are committed to delivering measurements made in Brazil that meet the highest standards of quality and reliability worldwide.

Different lenses used for optical frequency measurements.
Our photographer Mark Van Marx, taking photographs of optical frequency measurement lenses
A top view of the Quantum Optics measuring apparatus
Our special correspondents Mark Van Marx (photographer), Martin Butera (journalist), by the side of the sophisticated equipment of measurements of optical frequencies (Menlo Systems)

By way of final conclusion

From ancient times we have designed devices that allow us to measure time and keep it for records.

In the beginning it was carried out according to the nature, like the Sundials, which use the light to indicate the time; or the movement of grains of sand inside an hourglass, or water in the case of the clepsydra.

Subsequently, more precise devices were invented, whose operation occurs thanks to the standardisation of the time units (days, hours, seconds, etc.) of the International System.
Up to now, the most accurate of the clocks invented by humanity the atomic clock, calibrated from the vibrations of the atom of Cesium.

That now is our most modern and new starting point in what we refer as time.

Special Thanks

Final thanks, once again to Dr. Ricardo Carvalho, Head of the Service Division, the Official Time (DSHO), for freely allowing the photographers who accompanied me to cover the subjects of this report.

They are: Mark Van Marx (Photographer) and Ligia Katze (Videographer), Engineer Ozenildo de Farias Dantas, Mrs. Vilma Madalena de Assis Souza (Assistant in the Service of the C & T Division of the National Observatory Time) and Miss Letícia Reitberger (journalist of the communications consultancy Target).

To my friend, the Argentine radio listener Daniel Camporini, for writing a special prologue for this report (included in the Spanish version).

To my editor in chief, dear Chrissy Brand, for giving me the opportunity to work in South America, as a journalist for the BDXC.

Chrissy brand is European DX Council Secretary-General – BDXC Communication (http://bdxc.org.uk/).

To the dear friend and listener from India, Sudipta Ghose (VU2UT) for his adaptation to English and correction, member of the Indian DX club International (www.idxci.in)

To my friend Ivan Dias da Silva Júnior, director of the Regional DX – Sorocaba-Sao Paulo- Brazil, who collaborates in the Portuguese translations and publishes this material in the form of a micro book, for the club he directs (https://ivandias.wordpress.com/).

Finally my friend Thomas Witherspoon, director “The SWLing Post”, for publishing this report and collaborating in this way to the world of radio listening.

From left to right Mark Van Marx (in photo), Martin Butera (Journalist), Ricardo Carvalho head of the Service Division of the Official Time (DSHO), Miss Letícia Reitberger (journalist of the communications consultancy Target) and the lady Ligia Katze (Videographer), in the Generation, Conservation and Dissemination room of the time.

From left to right Martin Butera (journalist), Engineer Ozenildo de Farias Dantas and Mark Van Marx (Photographer), in the Generation, Conservation and Dissemination room of the time.
From left to right, Mark Van Marx (in photo), Mr. Dr. Ricardo Carvalho, head of the Service Division, the Official Time (DSHO) and Martin Butera (Journalist), in the laboratory.

 

About the author

Martin is an Amateur Radio operator with more than 29 years of experience, and has participated in DXpeditions throughout South America, with the Argentine radio callsign LU9EFO and Brazilian callsign PT2ZDX.

It is to collaborate for the newsletter of the British Dx Club (United Kingdom).

Martín is the founder of the Brazilian CREW Radio Listeners’, called 15 point 61 (15.61). Martin is Argentinian, born in the city of Buenos Aires capital. He currently lives in Brasilia DF, capital of Brazil.

Martín Butera is a journalist, documentary maker and founding member of Radio Atomika 106.1 MHz (Buenos Aires, Argentina) www.radioatomika.com.ar

About the The British DX Club

Martin Butera is a contributing journalist for “Communication” magazine of the prestigious The British DX Club. We congratulate Martín Butera for this interesting report.
If you would like to be a member of the Briitish DX Club, you can find information here http://bdxc.org.uk/apply.html

Report made, visit to Rio de Janeiro Brazil, in May 2019, written completed and published in SWLing Post in the middle of September 2019.

Please contact Martin at the following email address: martin_butera@yahoo.com.ar

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Jack’s Tailgate DXpedition

Many thanks to SWLing Post contributor, Jack Blanke (WB5LVP), who shares the following:

Really enjoyed your article yesterday, and felt compelled to respond with a similar DX’ing jaunt of mine two days ago.

I found myself in the same mindset and ventured out to a nearby peaceful fishing and yacht harbor to try out my new Tecsun PL-380. I have had it about 10 days and I have figured out that I have about all the urban power line and electrical noise I can stand at my home location, so I was headed out to give the 380 a chance to exercise its ears.

I found the most deserted corner of the parking lot at the harbor, positioned my pick-up for maximum shade, dropped the tail gate to provide a work surface, strung out about 75 feet of stranded #14 insulated copper wire and positioned my portable chair for DX action.

I did not have a copy of the WRTH, but I do use an iPhone app called Shortwave Broadcast Schedules by Black Cat that has really worked well for me and I highly recommend. With great anticipation, I flipped the power switch and enjoyed the most beautiful silence from man made electrical noise that I have ever experienced!! I could not believe how much quieter the receiver was in a more more pristine environment.

Jack’s ultralight Tailgate DXpedition kit

I opened the app to search for some DX’ing frequency possibilities, began tuning the bands and I was amazed at the number of short wave broadcast stations, the strength of their signals and the pure listening quality coming out of my 380, which is little larger than a pack of cigarettes!! I have been a licensed ham since 1970 and at one point back in the early 1970’s, I had a complete R. L. Drake HF station which might be called “Boat Anchors” by today’s standards. I was now listening to stations from around the globe on a receiver that comfortably fit in my pocket and a long wire strung out to a nearby “NO PARKING” sign post.

The Tecsun PL-380

Within a matter of a couple of relaxing hours, I had logged and enjoyed listening to Radio Habana, Voice of Vietnam, China Radio Int., Voice of Nigeria, Radio Romania Int., KBS World Radio and several other stateside shortwave broadcasts from Miami, Nashville & Lebanon Tennessee. I was totally thrilled at the performance of the radio/antenna combo and I anxiously await the opportunity to visit the area again for another Tailgate DXpedition!! I am particularly looking forward to fall days and cooler temps to go lose myself in the reverie of the shortwave bands, this time with a few brewskies in the ice chest, along with lunch.

It was a thoroughly enjoyable day and I could not help but relate to your article when I read it!! Next time, I plan to photograph my Tailgate DXpedition, simple though it may be to share with others. I have been away from radio for some time, but have maintained my amateur license for nearly 50 years. Now that I am retired and have more time, I plan to enjoy my long lost love of radio once again.

Thanks for your web sight. I look forward to the newsletters and enjoy its resources.

Take care.

’73’s
Jack Blanke

Thanks so much for sharing your story, Jack!

Isn’t it amazing how the shortwave bands simply open up when you remove all of the urban noise that plagues our receivers? That’s the brilliance behind impromptu DXpeditions. Plus, I’ve always believed that radio is best enjoyed outdoors.

We look forward to seeing some photos and a report of your next Tailgate DXpedition, Jack!


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