Re: [HCDX] Dxers Unlimited script for 27-28 October 2007 ZERO SUNSPOTS FOR MANY DAYS !!!

["Prof. Arnaldo Coro Antich" <inforhc@xxxxxxx>]

Radio Havana Cuba
Dxers Unlimited
Dxers Unlimited’s weekend edition for 27-28 October 2007
By Arnie Coro
Radio amateur CO2KK
Hi amigos radioaficionados around the world and in space… welcome to the 
weekend edition of Dxers Unlimited, RHC’s twice weekly radio hobby 
program. I am Arnie Coro, radio amateur CO2KK, now ready to share with 
you about seventeen or maybe eighteen minutes of on the air and on the 
world wide web time. By the way, we are on the WEB streaming audio from 
05 to 07 UTC from our website located at www.rhc.cu... Now here is item 
one of today’s program , the extended period of extremely low solar 
activity that has totally changed the previous analysis by scientists 
about the present solar cycle minimum… Comparisons between this cycle 23 
and the previous one, cycle 22 that went trough its period of minimum 
activity during part of 1996…
Scientists are now puzzled with what is happening, as they didn’t expect 
that the average number of sunspots went as low as it has gone during 
the extended minium of cycle 23… More about the November of 2007 solar 
forecast and how it had to be changed later here at the weekend edition 
of Dxers Unlimited… Now here is item two:  Worldwide amateur radio 
single side band contest now in progress… you may be able to pick up 
some really nice Dx stations operating from exotic locations like the 
Galapagos Islands…It will last until the end of Sunday UTC day… CQ Radio 
Amateur Magazine is the sponsor of this ham radio competition that is 
one of the most popular among the world’s amateur radio operators. Item 
three: Our technical topics section is now on the air with information 
about a rather unsual radio frequency detector circuit using light 
emitting diodes of different colors, that require the use of very high 
local oscillator injection voltages , something that gives this circuits 
a unique property of handling very strong signals.  Green light emitting 
diodes as well as blue ones have already been tested at my workshop 
under experimental conditions, feeding a seven megaHertz signal from a 
very nice signal generator… and Saturday I will be testing another 
broadband double balanced mixer using white-blue light emitting diodes 
that require between 3.2 and 3.8 volts to operate. The product detector 
circuit is followed by a high gain low noise audio amplifier, that has a 
variable gain setting with a range between 50 and 100 dB… When the light 
emitting diodes product detector is connected to a radio frequency tuned 
circuit , and that circuit is coupled to an antenna, we have a very 
special direct conversion receiver with a unique feature of handling 
very high input signals without overloading…
Item four: Coming up after a short break, is our most popular section of 
the program, ASK ARNIE, answering your questions on the air and also 
directly to your e-mail address… Standby for a few seconds amigos…
………
This is Radio Havana Cuba, the name of the show is Dxers Unlimited and 
here is item three ; ASK ARNIE, answering a radio hobby related question 
sent by listener Carlos from Mexico City, one of the worlds most 
populated cities… Carlos asks what he can do to reduce the extremely 
high noise level he is picking up with his two radios, on frequencies 
from 100 kiloHertz all the way up to around 25 megaHertz. He adds that 
above 25 megaHertz the noise level goes down on both radios, the small 
portable and the tabletop digital dial receiver. Carlos has tried 
several antennas and he tells me that so far he hasn’t been able to 
listen to weak stations on the international short wave bands… and I 
quote from his e-mail “ Arnie, only the most powerful broadcast stations 
are able to go over the very high noise level… the weak ones simply 
can’t be heard. Well amigo Carlos, you may want to try a unique antenna 
that I have tested here under high noise level conditions with excellent 
results… It is also not too difficult to homebrew, and can even null the 
most powerful noise sources by turning it around. This type of antenna 
is known as a magnetic loop, and is nothing more than a big one or two 
turn coil tuned by a variable capacitor, to which another smaller loop 
is coupled. The circuit diagram of this type of antenna can be 
represented as a standard parallel tuned circuit with a link coupling to 
your radio. A typical receive only MAGNETIC LOOP can be built in a few 
hours, and you can use it indoors… right next to your radio receivers, 
because this type of antenna requires constant tuning when you change 
the operating frequency of the receiver by just a few kiloHertz. The 
antenna is typically used right next to your receiver, because as I 
already explained, you must constantly retune the variable capacitor to 
peak the antenna’s very sharp resonance … at the lower end of the tuning 
range of this one meter per side square antenna using a 300 picofarads 
maximum capacity variable capacitor the tuning is so sharp that just 
tuning your radio maybe ten kiloHertz up or down from the previous 
frequency will reduce the signal level by twenty or even thirty 
decibels…So, as you can imagine, using this antenna amigo Carlos is not 
very comfortable, because you must retune it constantly, BUT, for people 
having to deal with extremely high noise levels as is your case , the 
Tuned Magnetic Loop antenna is according to my experience practically 
the only alternative that you can put to work .
……
Yes amigos, solar minimum is very much with us at this moment… many, 
many days without a single sunspot… many, many days of a blank Sun with 
the microwave solar flux measurements reaching bottom low figures that 
were not seen by scientists in many years, and as a matter of fact some 
solar researchers now believe that something is really changing 93 
million miles away from Earth… as solar cycle 23’s minimum has already 
reached rock bottom low levels with the average number of sunspots going 
down to around 5… yes, you heard it right ZERO FIVE , and that is half 
the number of sunspots registered during the minimum of previous solar 
cycle 22 during 1996…
This solar minimum may open up the question of the possible beginning of 
yet another Maunder Minimum ; that’s the name given to a long period of 
extremely low solar activity that happened between the years 1645 and 
1715, a period of a bit more than 70 years , or the duration of roughly 
six consecutive solar cycles that have an average duration of 11.1 
years. Astronomer Edward W. Maunder born in 1851 and who died in 
1928,was the discoverer of that extended period of extremely low solar 
activity  when he analyzed the records of solar optical observations . 
Maunder found out that during one 30 year long period within the a bit 
more than 70 years of very low activity, solar astronomers were able to 
count only about 50 sunspots , while the normal count for three typical 
consecutive solar cycles is  within the range of forty to fifty thousand 
sunspots… a one thousand to one ratio ….One outstanding characteristic 
of the Maunder Minimum was that
The sunspot activity was then concentrated in the southern hemisphere of 
the Sun, except for the last cycle when the sunspots appeared in the 
northern hemisphere too.
According to Spörer's law, at the start of a cycle spots appear at ever 
lower latitudes, until they average at about lat. 15° at solar maximum. 
The average then continues to drift lower to about 7° and after that, 
while spots of the old cycle fade, new cycle spots start appearing again 
at high latitudes.
The Maunder Minimum coincided with the middle — and coldest part — of 
the so-called little ice age, during which both Europe and North 
America,and perhaps much of the rest of the world, were subjected to 
bitterly cold winters. Whether there is a causal connection between low 
sunspot activity and cold winters is the subject of ongoing debate 
connected to the effects of global warming.
So amigos, for us radio hobby enthusiasts that are dependent on solar 
activity in order to be able to enjoy short wave propagation conditions 
that open up the higher frequency bands , that is those above 20 
megaHertz , the current solar minimum has already had significant 
effects, with extended periods of very poor propagation , with the 
nightime maximum useable frequencies some days not even reaching above 7 
megaHertz… and the maximum useable daytime frequencies not going above 
seventeen or eighteen megaHertz for brief periods… Scientists have 
already studied
Other historical sunspot minima have been alsodetected either directly 
or by the analysis of carbon-14 in ice cores or tree rings; these 
include the Sporer Minimum (1450–1540), and less markedly the Dalton 
Minimum (1790–1820). In total there seem to have been 18 periods of 
sunspot minima in the last 8,000 years, and studies indicate that the 
sun currently spends up to a quarter of its time in these minima.
……
Si amigos, we do QSL, we do verify reception reports, and send a nice , 
beautiful QSL card upon receiving your detailed reception reports that 
should include the date, time, frequency and some details of program 
contents. Send your signal reports to arnie@xxxxxx or VIA AIR MAIL to 
Arnie Coro, Radio Havana Cuba, Havana, Cuba
And now my friends, here is Arnie Coro’s Dxers Unlimited’s propagation 
update and forecast…  Expect more days of zero sunspots Zero, zero, zero 
sunspots for almost 20  days in a row now.  A single small
sunspot appeared briefly October 6-7, then no sunspots for four days
prior, one sunspot for the final few days of September, and none for
the three whole weeks prior to that.

Until recently, solar scientists were believing that the solar cycle 
minimum had occurredin March of this year, something that the present 
period of zero sunspots has proven to be wrong.  With such a long period 
of so few sunspots, at the beginning of November we might see a much 
lower 3-month average.  This is because the sum of all the daily sunspot 
numbers from August 1 until now is only 492, and if we still see no 
sunspots through next Wednesday, when November begins, that total 
divided by the number of days for August-September-October (92) is only 
5.4.a much lower figure than the September of 1996 minimum of 8.7 sunspots…
Hope to have you all listening to our show’s midweek edition next 
Tuesday and Wednesday UTC days amigos !!! Send your signal reports and 
comments to arnie@xxxxxx or VIA AIR MAIL to Arnie Coro, Radio Havana 
Cuba, Havana , Cuba

---[Start Commercial]---------------------

Preorder your WRTH 2007:
http://www.hard-core-dx.com/redirect2.php?id=wrth2007
---[End Commercial]-----------------------
________________________________________
Hard-Core-DX mailing list
Hard-Core-DX@xxxxxxxxxxxxxxxx
http://montreal.kotalampi.com/mailman/listinfo/hard-core-dx
http://www.hard-core-dx.com/
_______________________________________________

THE INFORMATION IN THIS ARTICLE IS FREE. It may be copied, distributed
and/or modified under the conditions set down in the Design Science License
published by Michael Stutz at 
http://www.gnu.org/licenses/dsl.html