*Dxers Unlimited mid week edition for 19-20 October 2004-*

*By Arnie Coro*

*radio amateur CO2KK***

*Hi amigos ,its nice to have you listening to the mid week edition of
Dxers Unlimited, I am Arnie Coro, radio amateur CO2KK, and today, we
have a special report about our practically all new Bauta transmitting
station, where five out of seven short wave transmitters are already in
operation for our regular broadcasts, and one of them is on loan to
Radio Rebelde's Tropical Band service operating with 50 kiloWatts on
5025 kiloHertz with a new omnidirectional antenna designed by my good
friend BAUTA'S chief engineer Hector Esperon. I'll tell you more about
the progress of the project to modernize Radio Havana **Cuba**'s
transmitting facilities after a bit more than 40 years of continuos
service of our Brown Boveri and Snieg transmitters... Item two will be
totally solar cycle related, with an in depth report about the recent
two days in a row without sunspots in sight, then item three will be our
technical topics section, with the description of a compact antenna for
the 80 meters amateur band, now that solar cycle 23 is definetely coming
to an end... And at the end of the program, as always when I am in
Havana, have your notepad or tape recorder ready for my exclusive and
not copyrighted HF propagation update and forecast...Stay tuned, as the
mid week edition of Dxers Unlimited continues in a few seconds... Jose
Costa Pupo is my sound engineer and producer , I am Arnie Coro*

*This is the mid week edition of Dxers Unlimited, and here is item two,
a detailed description about how solar scientists are seeing the end of
solar cycle 23 approaching...American solar scientist David Hathaway and
his Cuban colleague Angel Gonzalez Coroas have been watching the Sun
every single day since 1998, and both of them, for six long years have
written down the daily solar observations report , registering on every
single day a certain number of sunspots seen with their
telescopes.*Sunspots are planet-sized "islands" on the surface of the
sun. They are dark, cool, powerfully magnetized, and fleeting: a typical
sunspot lasts only a few days or weeks before it breaks up. As soon as
one disappears, however, another emerges to take its place.

Even during the lowest ebb of solar activity, you can usually find one
or two spots on the sun. But when both Angel and Hathaway looked on Jan.
28, 2004, there were none. The sun was utterly blank. Angel send me his
monthly report for January with a note: Coro, the first signs of the end
of cycle 23 have reached us, a blank Sun on the 28^th day of January
2004.. NOW, the two scientists have registered the same event...
absolutely no sunspots , but not one day, but two days in a row !!!

It happened again last week, twice, on Oct. 11th and 12th. There were no
sunspots.

"This is a sign," says Hathaway, "that the solar minimum is coming, and
it's coming sooner than we expected." Angel Gonzalez Coroas, the leading
Cuban solar observer coincides with his American colleague... He state
that thiw is a sign that solar cycle 23 is going to end sooner than
expected/

Now let me tell you more about the SOLAR CYCLE

Solar minimum and solar maximum--"Solar Min" and "Solar Max" for
short--are two extremes of the sun's 11-year average duration activity
cycle. At maximum, the sun is peppered with spots, solar flares erupt,
and the sun hurls billion-ton clouds of electrified gas toward Earth.
It's a good time for sky watchers who enjoy auroras, but not so good for
astronauts who have to be wary of radiation storms. Power outages,
zapped satellites, malfunctioning GPS receivers--these are just a few of
the things that can happen during Solar Max.



Solar minimum is different. Sunspots are fewer--sometimes days or weeks
go by without a spot. Solar flares subside. It's a safer time to travel
through space, and a less interesting time to watch polar skies.

Hathaway and Gonzalez are both expert forecasters of the solar cycle. He
keeps track of sunspot numbers (the best known indicator of solar
activity) and they are now predicting years in advance when the next
,minimum is going to happen..

"Contrary to popular belief," says Hathaway, "the solar cycle is not
precisely 11 years long." Its length, measured from minimum to minimum,
varies: "The shortest cycles are 9 years, and the longest ones are about
14 years." What makes a cycle long or short? Researchers aren't sure.
"We won't even know if the current cycle is long or short--until it's
over," he says.



But researchers are making progress. Hathaway and colleague Bob Wilson,
both working at NASA's Marshall Space Flight Center, believe they've
found a simple way to predict the date of the next solar minimum. "We
examined data from the last 8 solar cycles and discovered that Solar Min
follows the first spotless day after Solar Max by 34 months," explains
Hathaway.

The most recent solar maximum was in late 2000. The first spotless day
after that was Jan 28, 2004. So, using Hathaway and Wilson's simple
rule, solar minimum should arrive in late 2006. That's about a year
earlier than previously thought.

The next solar maximum might come early, too, says Hathaway. "Solar
activity intensifies rapidly after solar minimum. In recent cycles,
Solar Max has followed Solar Min by just 4 years." Do the math: 2006 + 4
years = 2010.

So amigos, get ready for those long periods of very low solar activity
when only the lower frequencies will propagate via the ionosphere... !!!
That's why today, I will be presenting my new compact 80 meter band
antenna, that is a little less than half the size of a standard half
wave dipole for the 3.5 to 4.0 megaHertz amateur band, where many of us
will have no other choice but to operate during solar minimum, as even
the extremely popular 40 meter band will be closing early during the
months of extremely low solar activity !!!.

.....

Si amigos, yes my friends, six brand new 100 kiloWatt short wave
transmiters are now under a test period at our Bauta transmitting
station. located about 20 miles west of the city of Havana. The new
transmitters are energy savers, as they used a modulation technology
that is know as PSM, or pulse step modulation, that makes possible the
design of a much more simpler and reliable transmitter than a classical
high level plate modulated one. Our new PSM transmitters provide
excellent modulation quality and they are capable of fast frequency
changes, something that is essential under today's crowded international
short wave broadcast band conditions. We are also installing six new
high gain curtain antenna arrays, and three omnidirectional ones, that
are all easily accessed from a sophisticated switching matrix, that is
operated from the control room.The new antennas will take still a few
months to be completed, so in the meantime, Chief Enginner Hector
Esperon, has kept the new transmitters under test using some of our old
antennas at Bauta, including the New York rhombic, our Caracas high gain
rhombic , the Caribbean phased array of dipoles and two of our
omnidirectional test antennas... now we must start testing the new
curtains one by one, and that is going to take quite some time, and of
course we will be needing our listeners reports to know how well the new
antennas are working !!!

..... Cortina

Si amigos, you are listening to the mid week edition of Dxers Unlimited,
and let me add that if your picking up our program on 11760 kiloHertz,
then you can be sure that it's one of our new pulse step modulated 100
kiloWatt transmitters... Now here is item four: As you have heard here a
few minutes ago, solar minimum is much nearer than what scientists
thought , so plans to upgrade the low frequency band antennas for your
short wave listening post or amateur radio station are to be given high
priority. That's why I am offering to all Radio Havana Cuba's Dxers
Unlimited's listeners the complete building instructions for homebrewing
two compact antennas, that are approximately half the size of a regular
standard half wave dipole. The two compact antennas, one for 80 meters
and the other for 40 meters, have been troughly tested, and perform very
nicely, making it possible for many radio amateurs to operate from small
urban locations, where space is at a premium. The data file for the step
by step instructions is very small, and in text format, so it can be
sent via e-mail without becoming an attachment, something helpful
nowadays, as many computer systems administrators have set barriers to
e-mail attachments in order to avoid harmful programs from entering 
Send for the 80 and 40 meter band compact antennas file, via e-mail, or
VIA AIR MAIL/// My e-mail address is very easy to remember, arnie@rhc.cu
<mailto:arnie@rhc.cu>, again arnie@rhc.cu <mailto:arnie@rhc.cu>, and the
postal address is also easy to remember... Arnie Coro, Radio Havana
Cuba, Havana, Cuba The compact antennas use computer designed loading
coils that can be easily homebrewed by the radio amateur or short wave
listener. They use easy to obtain PVC water pipe for the coil forms,
that admittedly are slightly less efficient than expensive high quality
and hard to obtain ceramic coil forms, but, the very slight loss in
efficiency is more than compensated by the low cost of the PVC water
pipe, and its universal availability.The two coils are wound using
common PVC insulated wire, that can be bought at any hardware store of
electrical supplies department of even a super market, and the center
and end insulators I have used here, are also made from PVC high
pressure rating white colored water pipe, that is the one that will
provide a longer life when exposed to the Sun's ultraviolet rays. SO
amigos, low frequency antennas are thw way to go during sunspot minimum,
and here I am offering two easy to homebrew designs that are available
just for the asking... send your request for the 80 and 40 meter compact
dipoles to arnie@rhc.cu <mailto:arnie@rhc.cu>, or VIA AIR MAIL to Arnie
Coro, Radio Havana Cuba. Havana , Cuba

And just before going QRT, here is our exclusive and not copyrighted HF
plus low band VHF propagation update and forecast. Solar flux now moving
up, with the daily flux passing the critical 100 units mark by the time
you hear this program. We may see solar flux numbers moving to as high
as 130 units during the next few days. No signs of coronal holes , so
the geomagnetic field is wonderfully quiet. Excellent autumn propagation
conditions prevailing for the next few days, and we may even see some
nice 10 meter band openings near local sunset. See you all at the
weekend edition of the program amigos, and don't forget to send your
signal reports and comments to arnie@rhc.cu <mailto:arnie@rhc.cu> !!!
I'll be surely waiting for them !!!