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Re: [HCDX] Dxers Unlimited's weekend edition for 29 -30 September 2007



Radio Habana Cuba
Dxers Unlimited
Dxers Unlimited's weekend edition for  29-30 Sept 2007
By Arnie Coro
Radio amateur CO2KK

Hi amigos radioaficionados! Welcome to the weekend edition of your 
favorite radio hobby program... the one and only that tries hard to 
cover all the more than 81 ways that you and I enjoy this wonderful 
pastime: RADIO... covering from the extra low frequency kilometric waves 
to the microwaves just touching light... and we even do talk about light 
communications from time to time too, as they are becoming popular among 
radio amateurs... Well, here we go again with the sad news of a terrible 
hurricane making landfall and causing loss of life and doing huge 
damages to people's homes... and once again amateur radio operators 
volunteered to provide much needed emergency communications. The two 
most recent tropical hurricanes that hit Mexico and Central America 
provided an excellent example of how amateur radio communications is 
able to provide much needed links to deliver aid to the badly hit areas 
immediately after the storm is over... Amateur radio operator’s e went 
to places that were assigned to each of them in case of a natural 
disaster, and they immediately installed their stations, ready to 
provide links with shelters, dams, hospitals and local government agencies.
Among the many lessons learned during each hurricane emergency there are 
two that I wish to share with you mis amigos, listeners of Dxers 
Unlimited that are also amateur radio operators... I'll go trough them 
later as the program's weekend edition continues in a few seconds...
I am Arnie Coro in Havana, and this station you are now listening to is 
Radio Havana Cuba, on the air since 1961!!!
.......
Si amigos, you are listening to the weekend edition of your favorite 
radio hobby program, and I want to thank the many listeners that have 
sent e-mail messages, letters and postcards not only reporting reception 
of the show, but also providing me with very valuable comments and ideas 
on how to improve the program...Now, some information about RHC 
transmitter tests that will soon be on the air on the Tropical Band 
frequency of 5055, again the frequency 5055 kilohertz, and.. Again the 
test frequency is going to be 5055 kilohertz and we may also be testing 
on another lower frequency on that same 60 meters Tropical Broadcast 
Band soon.
Now back to item one: Every time that there is a hurricane related 
emergency, amateur radio station operators learn more on how to handle 
the different situations. During the recent most recent storms, one of 
the lessons learned was that we all needed to have more storage 
batteries available at the sites where the stations were operating, and 
that those storage batteries must be fully tested, charged, and then 
discharged and charged again, to be really sure that they will be in 
perfect state, so as to provide the ampere hours for which they were 
designed.... At CO2KK my ham radio station that is used as the 
International Amateur Radio Union Emergency Coordination Station for 
AREA C of ITU Region II, one of my two 12 volts car batteries that I 
thought was in a very healthy state, proved to be in bad shape, and I 
later found out that one the cells was in a short circuit condition, 
something that reduced the voltage dramatically and made the accumulator 
useless for all practical purposes. CO2KK's batteries at charged during 
the emergency at a nearby facility that has a brand new 25 kilovolt 
ampere diesel generator...But that facility is located about three 
blocks away from my home, and as everyone knows, you can't go out in the 
middle of the hurricane... so if your batteries fail while the heavy 
winds and rain are blasting your place, then your emergency station 
simply goes off the air, until the storm is over and you can walk with 
the batteries to the place where the generator is located !!!
LESSON Number two:  Prepare reserve indoor antennas for your specific 
location, and do remember that if properly built and installed, an 
indoor antenna can keep your emergency station on the air even at the 
peak of the storm, when very probably your main antenna system sustains 
heavy damage due to the fierce winds of the hurricane or what may also 
happen, that somehow the heavy rainfall is so powerful as to force water 
into the coaxial connectors and render your antenna system useless. And 
of course this takes us to LESSON Number three: it is vitally important 
to protect all antenna connections to the coaxial cable downleads with 
the best possible sealing, in order to prevent the dramatic loss of 
communications when they are most needed. My elder son , Arnie Jr. radio 
amateur CO2KK, specializes in providing protection against the weather 
to antenna systems, and I have witnessed that after seven years exposure 
to the severe tropical weather conditions of Cuba, a shortened dipole 
antenna for the 80 meters band connection to the coaxial cable was in 
like new condition when I disassembled it after taking the antenna down 
for what I expected to be a total replacement, which of course, was not 
needed at all due to the excellent protection provided when it was 
installed...
The Atlantic Hurricane Season is still in progress, and we have the 
whole of October and November to go, so for those of you that are 
located in areas where tropical storms may make landfall, now it's good 
time to review your emergency communications systems capability and 
prepare for any possible future event...
Let's hope you won't ever need to use your ham radio gear for that type 
of service to the community, but amigos, it's better, it's always better 
to be prepared....
.....
This is the weekend edition of Dxers Unlimited... and here is good 
news... we have just passed the Autumn Equinox, but unfortunately, the 
Sun has remained spotless for an extremely long period... day after day 
with solar flux below 70 units and no sunspots have required scientists 
to readjust their forecasts for the minimum of cycle 23 several times 
now.... Even though solar activity is at extremely low levels, HF DX 
enthusiast continue to enjoy openings even with sunspot counts of ZERO 
day in and day out.... you may also catch openings on the 40, 30 and 20 
meters amateur bands, but, 17, 15, 12 and 10 meters remained closed for 
DX most of the time due to the extremely low ionization caused by the 
extremely low solar activity we are seen these days
  And now that I talk about 12 and 10 meters, let me say that we have 
already said good-bye to the F2 propagation on 12 and 10 meters until 
the next solar cycle generates enough activity to help the two higher 
frequency HF bands to make a comeback. No, I am not saying that  12 and 
10 meters won't open up occasionally, what I'm trying to say is that due 
to the very low average solar activity that will still prevail for the 
next several months, chances that 12 and  10 meters will open up for DX 
via the F2 layer are extremely low !!!
Item six:  Our popular antenna topics section will be devoted today to 
review some of my recent experiments with a unique antenna design, that 
has among its relevant characteristics a very low profile, while still 
retaining excellent low take off angle , essential for working DX... I 
have been doing more experiments with the FOUR Ls antenna system, and 
the more I test it the more I like it amigos... This experimental low 
profile antenna is now into a much more advanced stage of development, 
and much low budget low power AM broadcast stations are looking at the 
FOUR L as a possible alternative to replace the existing tall steel 
towers that they need to use. My experimental FOUR L antenna system for 
the 10 meters band was followed by an identical set up for 20 meters, 
and I'll keep you up to date with the results of the new 20 meters band 
FOUR L antenna, when propagation picks up and the band is in better 
shape. So far the 4 Ls antenna has shown excellent low take off angle, 
and what is really amazing is that the antenna height above the ground 
system is just two and a half meters, that is a bit less than eight 
feet, while a regular 20 meters band quarter wave vertical is five 
meters or 16 feet high... For those of you not familiar with the FOUR L, 
it consists of four pararell connected inverted L antennas that are fed 
at the starpoint using an impedance matching network. The antennas must 
be provided with a very good counterpoise or ground system, and 
experimental work with elevated radials seems to be a very attractive 
thing to do, as with just a few elevated radials, the FOUR L low profile 
antenna may provide the low take off angle required for working DX
Si amigos, yes my friends, the FOUR L experimental antenna is looking 
like a very promising development for those of us that cannot install 
tall masts or towers and still want to work DX on the 160, 80 and 40 
meters bands...and even for those that require low profile antennas to 
operate on the 30, 20, 17, 15, 12 and 10 meters amateur bands.
And now just before going QRT, here is Arnie Coro exclusive and not 
copyrighted HF plus low band VHF propagation update and forecast... 
Solar activity is now at very, very low level, with solar flux around 67 
to 70 units, and according to the latest optical observations of the Sun 
there is a very small sunspot, a really small sunspot in sight... a turn 
for the better after many, many days without a single sunspot. Trans 
equatorial VHF propagation on the SIX METERS band from Argentina, Chile 
and Brazil to the Caribbean and the southern United States should be 
happening now on a daily basis, usually after local sunset... AM 
broadcast band and Tropical Band dxers will enjoy excellent propagation 
conditions for the next two weeks or so due to the low solar activity 
combined with geomagnetic disturbances that distort low frequency 
propagation patterns especially at high latitudes, making possible to 
hear some unusual AM broadcast band DX... I. hope to have you all 
listening at the mid week edition of Dxers Unlimited amigos, and don't 
forget to set aside a little of your valuable time to send me your 
comments about the program, with any suggestions of topics to deal with, 
or ideas on how to improve this show that comes you with love from 
Havana twice weekly. My e-mail address is arnie@xxxxxx, and the postal 
address is Arnie Coro, Radio Havana Cuba, and Havana, Cuba...



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