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Re: [HCDX] Dxers Unlimited mid week edition for 25-26 December 2007 WITH SEASONS GREETINGS FROM HAVANA !!!

Radio Havana Cuba
Dxers Unlimited
Dxers Unlimited’s midweek edition for December 25-26 2007
By Arnie Coro
Radio amateur CO2KK

Hi amigos radioaficionados around the world and circling our planet in 
Earth orbit… Seasons greetings and a happy new year 2008 with more 
sunspots is my wish for you listeners of Dxers Unlimited that are now 
facing yet another chain of day after day of zero sunspots … That’s the 
end of solar cycle 23, yes it is, and we have yet to see at least one of 
two more high latitude and reverse magnetic polarity sunspot groups in 
order to be really sure that cycle 24 has already started. Do remember 
that solar cycles don’t switch from one to the other by turning off the 
old one and turning on the new one… Both solar cycles, the old and the 
new co-exist during several months and scientists believe that that’s 
exactly what is happening right at this end of the year 2007… More about 
HF propagation and a Sporadic E events forecast at the end of the show…. 
Item two: with zero sunspots and the solar flux down to baseline levels, 
the 21 megaHertz or 15 meters amateur band is absolutely dead for most 
of the local daylight hours, with maybe a brief opening , but that’s it, 
we will have to wait until solar flux stabilizes above 90 to 100 units 
to see 15 meters come back to life… meanwhile, as we wait for more 
sunspots , the 18 megahertz or 17 meters and the 17 megahertz or 16 
meters bands are the best daytime options for Dxers… 18 megahertz for 
radio amateurs and 17 megaHertz or more precisely from 17.5 megahertz up 
to 18 megahertz for short wave listeners that want to pick up 
international broadcast stations… Item three: with the Sun now again 
absolutely quiet, the night time reception of the lower frequency bands, 
from 100 kiloHertz up to 5 megaHertz is extremely good, providing 
excellent Tropical Band DX and also nice two way contacts for radio 
amateurs operating on the 160 and 80 meters bands… More radio hobby 
related information coming up in a few seconds, when Dxers Unlimited’s 
mid week edition continues after a short break for station ID… I am 
Arnie Coro in Havana …

You are listening to Radio Havana Cuba, the name of the show is Dxers 
Unlimited and yes, sure amigos, we do verify reception reports, we do 
QSL, and  Dxers sending reports  during the next few weeks with the 
postal mailing address included will be receiving our nice 2008 pocket 
calendar and RHC’s QSL… Now item four: Olivia is the name of a very 
interesting and rugged digital communications keyboard to keyboard mode 
that was created by Pavel Walotcha, the same Polish radio amateur that 
formed part of the team that started the digital revolution on the ham 
bands by launching the PSK31 digital mode and that together with Peter 
Martinez, a British radio amateur of Spanish ancestors, made the PSK31 
computer code freely available to the world’s amateur radio community in 
a very nice gesture that is fully appreciated by ham radio operators 
around the world. Now Pavel has provided us with Olivia, a wider 
bandwith mode that has an almost hard to believe capability of providing 
a communications link despite very weak signals and even under heavy 
interference from other stations near the same frequency the Olivia 
stations are operating. You can learn more about the Olivia keyboard to 
keyboard digital communications mode by running a search engine request 
with the words Olivia , the plus sign and then amateur radio, in order 
to obtain the fastest and most consistent results from your search. 
Olivia is very easy to use and my opinion is that it will be winning 
more and more users as radio amateurs now using PSK31 realize that with 
Olivia they can achieve better and more reliable communications. Amateur 
radio is constantly developing and digital voice is slowly growing, but 
that’s going to be the subject of an analysis at an upcoming edition of 
Dxers Unlimited.
Item five:  Also related to digital communications modes as used by 
amateur radio operators during this rock bottom end of solar cycle 23. 
Monitoring the 40 meters band during early Tuesday UTC day, that is 
shortly after 9 pm my local time, or zero two hours UTC, I found the 
band practically empty, with very few stations operating… After running 
a propagation analysis software program with the solar data for the past 
five days, I arrived at the conclusion that the maximum useable 
frequency was barely reaching seven megaHertz, something that explained 
why so few stations were heard.
During extended periods of extremely low solar activity the ionosphere 
becomes so weak after local sunset, that it is not surprising to see the 
maximum useable frequency to drop down below seven megaHertz an even 
lower amigos… That’s solar minimum at its worst !.
Item six, here it is , once again, your favorite section of Dxers 
Unlimited… LA NUMERO UNO… You have questions and Arnie tries to answer 
them… you can send your radio hobby related questions to arnie@xxxxxx , 
or VIA AIR MAIL to Arnie Coro, Radio Havana Cuba, Havana, Cuba.
Today’s first question came from a long time listener in India. Rajiv 
tells me that at this moment he is not able to pick up our station on 
the shortwave bands, and he rightly assumes that this is because of the 
very low solar activity… but Rajiv who lives in the garden city of 
India, Bangalore, the home of the nation’s electronic and other high 
tech industries, is able to read the scripts of the program that are 
made available to several short wave listeners clubs e-mail distribution 
lists. Rajiv tells me that he wants to obtain the electronic files of 
the Super Islander amateur radio transceiver to compare the circuit 
diagrams and design philosophy with a similar project that is becoming 
very popular among Indian radio amateurs.
Ok amigo Rajiv… I have already sent you all the files including some 
nice digital photos of the first prototype of the Super Islander, that 
as you will see, has two final amplifier options , one built using NPN 
RF power transistors, and the other one using two vacuum tubes that are 
very easy to find here in Cuba from recycled TV sets. The Super Islander 
is a single band transceiver that can be built for the 160, 80 or 40 
meter bands. Here in Cuba amigo Rajiv, the most popular amateur band 
nowadays is two meters, using the FM narrowband mode, and the second 
most popular band among Cuban radio amateurs is 40 meters, that’s why 
most of the Super Islanders are built for operating between 7.000 and 
7.150 kiloHertz.  The double sideband signal generated by the Super 
Islander simple circuit is very stable, and very few if any radio 
amateurs that contact stations using the Super Islander are able to 
detect that it is a double side band and not a single side band signal 
what they are hearing. One of the most outstanding features of the Super 
Islander single band amateur radio transceiver is that it is modular, so 
those who want to build it, are able to build and test each module as a 
single project, and after all the modules are fully tested, then they 
are easily wired together . The parts count, that is the number of 
components required to build a Super Islander was kept intentionally as 
low as possible, both to simplify its construction and to increase the 
reliability. I hope that amigo Rajiv in Bangolore , India will be able 
to make good use of the Super Islander’s files, and maybe even go ahead 
and build one , as the parts required are almost universally available, 
because that was one of the design requirements that I set when starting 
the  Super Islander project more than fifteen years ago….You can learn 
more about this simple amateur band transceiver by sending a request for 
the Super Islander files to arnie@xxxxxx … I will send it as a dot zip 
file and you will be able to see circuit diagrams, photos and full 
descriptions of the different modules of this nice little rig, that has 
proven itself under the most difficult circumstances, like handling 
emergency communications links during tropical storms.
Si amigos, yes my friends, oui mes amis, you are listening to the mid 
week edition of Dxers Unlimited, your favorite radio hobby program 
covering the more than 82 ways that you and I enjoy this wonderful 
hobby… from homebrewing a nice little ham band transceiver like the just 
mentioned Super Islander and then using it on the air, to watching a TV 
DX signal come and go when a Sporadic E cloud is providing enough 
ionization for a station operating on frequencies as high as
80 megaHertz to be seen more than a thousand miles away… Sure, radio is 
a fascinating hobby and you will never be bored with it, as there is 
always something new that can be done, like for example milliwatting, 
that is trying to make amateur radio two way contacts while running less 
than one Watt of power… one Watt is a thousand milliwatts, and that’s 
why this particular form of QRP or low power operation is also known as 
milliwatting.  I have a little transistorized transceiver for the 20 
meters band that can operate running even down to 100 milliWatts, or a 
tenth of a Watt , and amazing as this may sound to some of you , I have 
already worked 35 countries using the 20 meters CW transceiver while 
running it at the one tenth of a Watt power output level…There are 
several international radio clubs devoted to low power or QRP operation, 
among them the GQRP Club that edits the very fine SPRAT magazine that 
provides readers with very nice technical articles about low power 
radios and how to operate using them. The website of the GQRP club is 
located at www.gqrp.com , again the URL of the GQRP website is 
www.gqrp.com. Yes amigos, joining an amateur radio club is very 
important if you really want to be up to date on what’s going on in a 
particular field of amateur radio, in this case the GQRP club membership 
provides you with information about QRP contests, and a treasure chest 
of extremely useful tried and tested technical information that you can 
put to very good use when homebrewing amateur radio equipment…
And now amigos, as always at the end of the program, when I am here in 
Havana, ready to copy Arnie Coro’s Dxers Unlimited’s HF plus low band 
VHF propagation update and forecast… Solar activity is and will continue 
to be for the next several days at very low levels… Zero sunspots seen 
during the past six days… solar flux around 70 units and the spotless 
Sun is also free of coronal holes, so we will enjoy also an extremely 
quiet geomagnetic field, certainly good news for low frequency bands 
Dxers, both short wave listeners and radio amateurs… Expect more 
sporadic E openings to happen as we are now riding trough the peak of 
the winter E skip season… I wish you all Seasons Greetings and hope that 
next year you all will be listening to my Dxers Unlimited’s show, that 
as always, I will try to make it as attractive and interesting as 
humanly possible for your enjoyment… Happy New Year amigos !

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