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Thursday, February 14, 2008

DXers Unlimited - Midweek Edition, February 12-13


RADIO HAVANA CUBA
DXERS UNLIMITED´S MIDWEEK EDITION FOR 12-13 Feb 2008
BY ARNIE CORO, CO2KK

Hi amigos radioaficionados all around the world, and moving in orbit around Planet Earth, with solar activity at rock bottom levels... it is really amazing to be able to hear the VP6DX Ducie Island expedition with such good signals here in the Caribbean,and also according to reports received, they are making many contacts in Europe too. Congratulations to the devoted group of radio amateurs that are providing the opportunity to work this rare DX spot, and I hope that the team will also QSL to the many short wave listeners that are expected to send QSL cards to them.

More about the Ducie Island amateur radio DX expedition later in the mid week edition of your favorite radio hobby program , Dxers Unlimited with yours truly Arnie Coro, radio amateur CO2KK at the microphone...

Item Two: A nice analysis of the role of the human voice in broadcasting started around the use here of a especially shaped audio frequency response curve that , it´s true, sounds almost like telephone quality because the lower frequencies are attenuated and the frequency range between 500 and 1500 Hertz or cycles per second are boosted in order to increase the talk power... We also cut abruptly above four kiloHertz, as very little information is sent with my voice above three point five kiloHertz... As a result of this shaping of the audio frequency response curve, Dxers Unlimited is heard better when propagation conditions are marginal, and also in areas where the signal from the station is normally very low because they are not the target of the broadcasts. Thanks to the Ontario DX Association mailing list, we learned that Andy Sennit, from Radio Nederland also used a specially tailored for his voice audio frequency response curve during the time that his popular Media Network program was on the air.

Item Three: During my recent visit to Venezuela I had the opportunity to meet with several well known radio amateurs there that are contests enthusiasts... and they told me that on 160 meters success was very much tied to the use of very effective Beverage type antennas. I fully agree with them and we also discussed about the K9AY receiving loop, an extraordinary antenna system by all standards, that the Venezuelan radio amateurs have also installed and used for their very succesful contest stations. The K9AY loop is not too difficult to homebrew and according to what I have heard about it, reception of the lower frequency bands, including the AM medium wave broadcast band is outstanding as compared with other loops.

More about our radio hobby and its more than 83 ways that you and I can enjoy it in a few seconds when the mid week edition of Dxers Unlimited continues after a short break for station ID. I am Arnie Coro in Havana... stay right on this frequency amigos..

You are listening to Radio Havana Cuba, the name of the show is Dxers Unlimited and YES, we do QSL, we do verify reception reports with a nice QSL card... Just send an e-mail to arnie at rhc dot cu and I will be sending you our QSL card to your postal mailing address VIA AIR MAIL.

Item Four: Some time ago an American broadcast band Dxers wrote to me asking about Radio Reloj, the 24 hours voice only news and information service of the Cuban Institute of Radio and Television, the Cuban broadcasting organization. Amigo Chuck from Utah told me in his e-mail that he could pick up several of the RADIO RELOJ´S relay stations, and that he wanted to know which one was the main station in Havana. Well amigo Chuch, RADIO RELOJ was founded in 1947 and it will soon be 61 years old ... its main station transmitter is on 950 kiloHertz and it runs 10 kiloWatts to a very efficient antenna system . The fact that RADIO RELOJ broadcasts on CW Morse Code its station ID with the letters R R, make it a very easy to verify station when you are trying to pick up DX on the AM broadcast band... the one kiloHertz tone with the audio keying of the letters RR is capable of drilling right trough the worst
iInterference conditions, and makes you sure that the station you are picking up is certainly RADIO RELOJ. By the way Radio Reloj is a national network that also has some transmitters on the FM broadcast band... here in Havana, the frequency used is 101.5 megaHertz and the transmitter power is about 10 kiloWatts effective radiated power... So when the upcoming Sporadic E skip season starts sometime in late April, if you hear Radio Reloj on 101.5, you can be sure that it is the City of Havana transmitter !!! The 24 hours of Radio Reloj´s programming is news and information in the voice of two announcers... You can hear two men´s voices, two women´s voices or in some cases a man and a woman reading the news at a speed of about 130 to 150 words per minute in very articulate Spanish... Radio Reloj´s Sunday programming is also voice only, but the words per minute is reduced to about 120 words per minute and each news item is read totally by one of the announcers. The weekend program is called ¨Revista Semanal¨or weekly magazine, and it shares the air time with news bulletins at the top of the hour and the half hour... And before leaving this topic let me add that the Radio Reloj station management does QSL. You can send your QSL requests to Radio Reloj , 23 no 258 and M street Vedado , Havana , Cuba, again , Radio Reloj 23 no 258, and M Street Vedado, spelled Victor Echo Delta Alpha Delta Oscar, Havana, Cuba...

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Item Five: More about my visit to Venezuela... Radio Nacional of Venezuela is now involved as I explained during the weekend edition of Dxers Unlimited, in reaching a nation wide expansion and modernization of its broadcast facilities, that includes he installation of a large number of FM broadcast band transmitters to increase the overage even to the most remote locations. The installation of several new AM broadcast ransmitting stations is also now in the works, using solid state transmitters and highly efficient folded monopole vertical antennas. Most of the new AM broadcast band sites will be serving two of Radio Nacional of Venezuela´s national programs, by means of a diplexer arrangement that allows using the same antenna system for transmitting two different

AM band frequencies . This is a very sound and economical approach that has been used for a long time by AM stations around the world, and now it is even a more efficient approach thanks to the use of the vertical folded and grounded monopole antennas, that also provide additional protection for the solid state output modules of the modern transmitters...

So, in the not too distant future, I am sure that Dxers in South America, the Caribbean Central America and North America will be able to pick up the new Venezuelan AM transmitters broadcasting Radio Nacional of Venezuela different programs, as several of these sites will be using power outputs in the 10 to 50 kiloWatt range... the kind of power that makes possible frequent DX pick up from distances of more than one or two thousand miles away...

But there is still more good news for short wave listeners around the world from Radio Nacional of Venezuela, their international service, CANAL INTERNACIONAL , is also part of the broadcast expansion plans, and a new short wave transmitting station is now under construction there. The new installation will include a 50 kiloWatt transmitter to be operated on the 60 meters Tropical Band, and five 100 kiloWatts short wave transmitters to be operated with several antenna arrays . The new transmitting station is located in the State of Guarico, and the antenna systems will include several high gain curtain arrays and also quadrant type omnidirectional antennas for short and medium range coverage. The new transmitters are of the pulse step modulation type, and very efficient from the point of view of energy conversion, that is that they are capable of producing a 100 percent modulated signal with much less electricity than what is required for a high level plated modulated transmitter.

The Radio Nacional of Venezuela engineering department is in charge of the project and it is expected that the first transmitter may be on the air pretty soon. The new Venezuelan international broadcasting facility is going to be one of the most modern and energy efficient installations in the Americas, and its antenna systems where designed with coverage of the Americas as the prime target area, but as expected , it may be heard around the world when propagation conditions are good. The old Venezuelan Radio Nacional 50 kiloWatt transmitter on 9540 kiloHertz may also soon be back on the air on that traditional frequency that has been in use by the station for many years.

At the present time Radio Nacional of Venezuela Canal Internacional is broadcasting via the Radio Cuba transmitters outside Havana , according to an agreement between the two nations.

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You are listening to Radio Havana Cuba, the name of the show is Dxers Unlimited, and you can send your signal reports, comments about the program and radio hobby related questions to arnie at rhc dotcu, again, very easy to remember and to type too... arnie at rhc dot cu..., VIA AIR MAIL you can get in touch by sending a postcard or letter to Arnie Coro, Radio Havana Cuba, Havana , Cuba... and now the weekend edition of Dxers Unlimited continues via short wave and from 05 to 07 UTC we are also on the world wide web via streaming audio from http://rhc.cu....

And now amigos, just before going QRT, now back in Havana, at RHC Studio 6 and with the audio frequency equalizer set for optimum response to my voice...here is Arnie Coro´s HF plus low band VHF propagation update and forecast. According to solar scientists we are still heading for more zero sunspots days... solar cycle 23 seems to be going to last for at least several more weeks... predictions call for extremely low solar activity , rock bottom solar flux near 70 units and lower, and zero sunspots for at least six more weeks... so , again we will see short wave propagation conditions will limited to the lower frequency bands, with daytime propagation reaching only up to 18 or 20 megaHertz. Night time maximum useable frequency on some paths will dip even below 7 megaHertz , something typical of extremely long periods of very low solar activity. Also be on the alert if you enjoy Dxing on the Low frequency bands Dxers, in the range between 100 kiloHertz and 2 megaHertz, because propagation conditions will be ideal during periods of quiet geomagnetic activity...

AM broadcast band conditions are ideal to bring in some rare and nice DX especially to the South of your location. Amateur radio operators that enjoy the use of the 160 meters 80 and 40 meters bands will be able to work some nice DX during the rest of February and early March... we will see possibly the best conditions for 160 meters for many years to come...

Hope to have you all listening to the weekend week edition of Dxers Unlimited , Saturday and Sunday UTC days, and don´t forget to send me your signal reports , comments about the program and radio hobby related questions to arnie at rhc dot cu, or VIA AIR MAIL to Arnie Coro, Radio Havana Cuba, Havana, Cuba..