Radio Habana Cuba
Dxers Unlimited
Dxers Unlimited's weekend edition for Oct 1-2 2005
By Arnie Coro
radio amateur CO2KK
Hi amigos radioaficionados !I am Arnie Coro, radio amateur CO2KK giving you
a warm welcome to the weekend edition of Dxers Unlimited that is reaching
you as our good friend the SUN, 93 million miles away from us seems to be
taking a break from the recent period of high activity... The optical
sunspot count is now way down, less than fifteen , and for all practical
purposes observers describe today's solar disk as practically blank... But
nowadays scientists are able to watch what's happening on the farside of the
Sun, and there, thanks to the sophisticated heliosysmic technniques, they
are watching an old friend , sunspot active region 798, that generated lots
of aurora borealis activity and geomagnetic disturbances during the months
of August and September.... So, based on these observations, I can tell you
that Long Wave, AM Medium wave and the Tropical Broadcast bands will be
under almost ideal propagation conditions, with very little ionospheric
absorption... For radio amateurs this very low solar activity and the non
presence of high speed solar wind gusts means that the 160 and 80 meter
bands will be an ideal playground for working DX from local sunset to local
sunrise... Item two:
Radio is a lot of fun, because you can play with your radios in many
different ways... for example, a very interesting challenge for medium wave
AM broadcast band Dxers is often overlooked... that challenge is simply
testing your receiving setup capability to pick up stations during the local
daylight hours, from two hours after local sunrise to about an hour before
local sunset... The only propagation mode available during those hours is
the so called ground or surface wave, and it is really amazing how a good AM
band Dxing setup can bring in stations from very far away via the ground
wave mode... More about daytime AM broadcast band Dxing later in today's
show...
Item three: The two meters amateur band, from 144 to 148 megaHertz in most
of the Americas, and from 144 to 146 in the rest of the world, continues to
be the number one most used frequency assignment devoted to amateur radio
use... The extensive coverage provided by mountaintop and high rise building
located repeaters, and the lower cost of a new generation of two meters band
handheld FM transceivers, popularly known as handie-talkies are keeping the
two meters band very active around the world.
Stay tuned for more radio hobby related information, coming to you from
Havana...my e-mail address ,is arnie@rhc.cu amigos, and if you are not yet
in cyberworld, just send your signal reports and comments about the program
VIA AIR MAIL to Arnie Coro, Radio Havana Cuba...
........
This is the weekend edition of Dxers Unlimited, and now, please listen to
item one in detail...
When everyone thinks about AM medium wave broadcast band Dxing, the mind
goes immediately to the local night hours...Staying awake all night long
until the Sun rises above the horizon, and ionospheric absorption
effectively kills the skywave. As many of you familiar with AM band Dxing
know, the existence of the highly absorptive D layer during the local
daylight hours, blocks the frequencies below about 2 megahertz or so from
reaching the E layer of the ionosphere.
Then the only available service from the AM stations operating from about
530 kiloHertz to 1710 kiloHertz is provided by the surface or ground wave,
that propagates along the surface of the Earth, and the attenuation of those
ground wave signals is very significant, so to explain it in simple language
the distance that AM stations may reach during the local daylight hours is
limited, and the lower the frequency that the station uses , the greatest
distance that it can reach via ground wave. In other words, AM stations
using frequencies between 530 and 800 kiloHertz will be heard at much
farther distances during the daytime daylight hours than those using
frequencies above 800 kiloHertz. As a matter of fact, experts split the AM
broadcast band into three frequency ranges... from the above mentioned 530
to 800 kiloHertz that provides the best ground wave signals, from 800 to
1200 kiloHertz that have a more limited range during daytime, and the
frequencies between 1200 and 1700 kiloHertz that are limited to much shorter
daytime coverage. Daytime AM dxing is also dependent on another very
important key element... ground conductivity, and that explains why daytime
reception of some stations is possible at impressive far away distances when
between the transmitter and the receiver the only the ocean is present. Sea
water has a very high conductivity, when compared to any type of land, so AM
signals traveling over the ocean suffer very little attenuation amigos ! AM
broadcast band daytime Dxing is one of the more than 70 ways you and I enjoy
this wonderful hobby, and you can be sure that by carefully tuning the range
from 530 to 1710 kiloHertz during the local daylight hours you will be able
to log in several stations that are really far from your location... Log
them in, and send their chief engineers a daytime report... I can assure you
that response to your QSL request is going to be much faster than when you
report AM band skywave DX at night !. Want to know why ? .... The answer is
very logical , AM stations are designed for local ground wave coverage, and
those are the reports that they can show to their advertisers in the case of
commercial stations or to those that provide the operating budget in the
case of non-commercial broadcasters !....
.......
Dxers Unlimited is on the air twice weekly, on Tuesdays and Wednesdays UTC
days, we present our mid week edition, and on Saturdays and Sundays UTC days
our weekend edition is on the air... Now we are also broadcasting Dxers
Unlimited via INTERNET streaming audio on our two hour English language
broadcast from 05 to 07 hours UTC, again, streaming audio feed from www
radiohc.cu, with Dxers Unlimited starting usually around 0533 UTC or a bit
later... Reports of our streaming Internet audio will be most appreciated
amigos, please send them to arnie@rhc.cu
Now here is item four: Si amigos, yes my friends, oui mes amis, radio is a
great hobby, and if you decide to explore the vast universe from your home..
then you can become an amateur radio astronomer, an aspect of the hobby
that , even with rather simple receivers and antennas, will allow you to
pick signals from the SUN, Planet Jupiter, and the stronger radio sources
outside of the solar system... Yes, solar radio astronomy is just a few
steps away for enterprising radio hobbysts that decide to explore this
fascinating aspect of our magic passtime : RADIO. Let me suggest that you do
an Internet search on any of the popular World Wide Web search engines ,
using the words radio astronomy, and amateur radio astronomy. You will be
pleasently surprised of the many hyperlinks to websites that will show up,
and from there on, learning about how natural radio waves from outer space
reach Planet Earth will be simply fascinating amigos !!!
.......
Bring more people into the radio hobby, join your local radio club,
subscribe to radio hobby printed magazines, subscribe to radio hobby e-mail
distribution lists and learn more about this wonderful hobby !!! Tell a
friend about your latest DX catch, tape DX signals and play them back to
your friends and acquaintances who show an interest in the hobby, have them
share your enjoyment. Amateur radio clubs , when properly organized are a
wonderful way of learning more about radio, and also provide the area where
you live with the very valuable service capability, with the unique
capability of amateur radio emergency communications, something that people
that have lived trough the very difficult times caused by natural disasters
know very well.
Three of my neighbors are now amateur radio operators, they own their own
ham equipment and became members of our Plaza Radio Club... Their interest
in the hobby came after learning about how ham radio stations provided vital
links during several hurricanes that affected Cuba... They knocked at my
door and asked how they could obtain their amateur radio licenses to own and
operate their own stations...Reynaldo, Marcelino and Ramil are now on the
air, joining the almost four thousand members of the Cuban Amateur Radio
Federation, the umbrella organization to the nations more than one hundred
and twenty radio clubs...
.......
Antenna topics, yes, the antenna topics section is here with a short tip
about HF antennas for the 80 and 40 meter bands specifically designed for
emergency communications using the near vertical incidence skywave
propagation mode.. For those of you interested in installing such antennas,
let me say that I have prepared a special NVIS antenna package, with lots of
valuable information about these special antennas that are capable of
providing very strong signals at relatively short distances on both 80 and
40 meters... Send for Arnie Coro's NVIS Emergency Antenna Package, and I
will send it to you via e-mail. Sorry, but I don't have at this moment the
capability of printing this little practical e-booklet, so the offer is
limited to e-mail requests... Send mail to :arnie@rhc.cu... again arnie@rhc
cu, the package includes three different antennas specifically designed for
the NVIS propagation mode...three antennas that you can easily homebrew and
keep ready to use at the time of an emergency...
.....
And now as always at the end of the show, when I am here in Havana, please
get ready to copy Arnie Coro's Dxers Unlimited HF propagation update and
forecast, including the special Low Band VHF report too... SOLAR ACTIVITY is
at a very low level... The number of sunspots below 15 ,and the 2800
megaHertz solar flux is almost exactly at baseline reference level, the last
reading I had access to was 72 units... No geomagnetic disturbances are
expected, so, the combination of very low solar activity, the equinoctial
period and low speed solar wind add up for the best propagation conditions
for Long Wave, Medium Wave and Tropical Band Dxing. For amateur radio
operators, transequatorial propagation on the 6 meters band is now in full
swing,and those living in the Caribbean may even see two meters band
openings to South America during the next several days... Don't forget to
take a little time and send me your valuable comments about this program,
your ideas on how to improve it, and of course, if you have any radio hobby
related question, send it to arnie@rhc.cu, again arnie@rhc.cu, and expect a
fast turnaround with the answer to your questions amigos !!!