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Re: [HCDX] From Arnie Coro Host of Dxers Unlimited
Radio Havana Cuba
Dxers Unlimited
Dxers Unlimited's weekend edition for 23-24 August 2008
By Arnie Coro
radio amateur CO2KK
Hi amigos radioaficionados ! You are most welcome to the weekend edition 
of Dxers Unlimited, coming to you from Havana, via short wave and also 
via the world wide web audio feed from http://rhc.cu in English from 05 
to 07 UTC.
I am Arnie Coro, radio amateur CO2KK, your host here in the sunny 
capital city of Cuba where the temperature at noon Friday was about 32 
degrees Celsius.
By the way at the time that I was recording the show, early morning 
Saturday the temperature was a bit cooler 24 degrees Celsius with the 
relative humidity at 70 percent... and yes , after the side effects of 
Tropical Storm Fay felt here on the western part of Cuba, once again we 
are enjoying a beautifully blue sky due to the presence of a high 
pressure ridge that may produce a nice tropospheric ducting opening at 
any time now.
As a matter of fact, this Saturday was ideal to go to the beach and also 
to generate a good tropo duct opening !!!
Now here is item one: One of the most popular ways of enjoying the radio 
hobby is, without any doubts,AM medium wave broadcast band Dxing, that 
according to the e-mail messages, postcards and letters received here, 
generates a lot of interest among listeners of Dxers Unlimited around 
the world.
Receivers and antennas especially designed for AM medium wave broadcast 
band Dxing will make a big difference on the results that you can 
achieve, while locations with very low noise levels and far away from 
high power stations are described by the avid AM Band Dxers as the ideal 
places where to go for a Dxexpedition.
With solar activity at an all time low for the past 11 years, we may be 
able to enjoy a very nice upcoming autumn equinox AM broadcast band DX 
season...
More about the extremely low solar activity that has prevailed since 
October of last year...
A detailed account of the way that the solar cycle has behaved in a few 
seconds, when the weekend edition of Dxers Unlimited will continue. I am 
Arnie Coro in Havana.
.........................
You are listening to Radio Havana Cuba, the name of the show is Dxers 
Unlimited , and here now is a detailed account of the solar statistics 
that clearly show that the Sun has gone trough two minimums.
The month of October of 2007 registered an extremely low monthly sunspot 
average of 0,9, that was followed by a very slightly higher figure of 
1.7 in November, then during December of last year activity increased to 
10.1 , only to take a dip to 3.8 during January, continue the downward 
turn in February to 2.1, and then March data shows a montly sunspot 
average of 9.3.
Some scientists thought that solar cycle 24 was starting , but they were 
wrong... April and May of 2008 average monthly sunspot count registered 
the same figure of 2.9, June was just slightly more active at 3.1 and 
then July brought the lowest monthly sunspot average of the whole cycle, 
just 0.5, that meaning that for practically 31 consecutive days solar 
optical observers saw a totally blank solar disc....
And to bring to an end this lenghty but very important statistical 
analysis, so far, during 22 days of the month of August, only a very 
small cycle 23 sunspot was seen . In total agreement with the zero 
sunspot count that has prevailed during August, the microwave solar flux 
at 10.7 centimeters way length has stayed at rock bottom levels , with 
an average very near the minimum ever registered of 64 units.
Now, after you have patiently heard those terribly low numbers, here is 
the analysis of what they may mean for the low frequencies DX 
enthusiasts, a crowd that includes operators of automatic low frequency 
beacons, listeners to the natural radio emissions of Planet Earth that 
include the often heard but not very well known whistlers, Long Wave AM 
broadcast band Dxers, the radio amateurs that are operating on the two 
thousand and two hundred meters band, non directional aviation beacon Dx 
hunters , the new group of radio amateurs that are operating on a 
segment of the old Marine 500 kiloHertz band, and those that are not yet 
allowed to transmit on the 600 meters band, but that as I am doing are 
constantly monitoring that new ham band in order to learn more about its 
unique daytime propagation characteristics.
But if you add the people devoted to the above mentioned ways of 
enjoying the radio hobby, they are no match to the hundreds of thousands 
of persons around the world that in one way or the other have a good 
time trying to pick up DX stations on the AM medium wave broadcast band, 
where practically every nation in the world has at least one station 
operating.
If the present extended period of very low solar activity continues 
during the months of September and October then AM medium wave broadcast 
band Dxers will enjoy a super DX season, because of the very low 
ionospheric absorption that will prevail during the upcoming autumn 
equinoctial period, that should be starting in about two weeks and 
extend at least until mid October.
Si amigos, yes my friends, oui mes amis, AM broadcast band Dxing , 
according to my propagation forecast, is going to be really amazing, and 
the only thing that could spoil this autumn equinox DX season will be a 
sudden , abrupt and so far unexpected increase in solar activity.
Get ready for what is going to be possibly the best AM band and Long 
Wave broadcast bands DX season in years to come... and stay tuned to 
this program , because our technical topics section for today will 
provide you with several nice tips for low frequency Dxing, in the range 
from 10 kiloHertz all the way up to 2 megaHertz, because, yes... the 160 
meters amateur band is also going to be excellent for Dxing during the 
upcoming autumn equinox...
..................
You are listening to Radio Havana Cuba, the name of the show Dxers 
Unlimited, and here is now our technical topics section, that is 
competing in popularity with our HF and low band VHF propagation updates 
and forecasts and even with ¨¨ La numero uno¨¨ the most requested and 
popular section of this program ¨¨ ASK ARNIE¨¨
So get ready to copy, here are several really practical and easy to 
follow tips for Dxing the low frequency spectrum from 10 kiloHertz all 
the way up to the end of the AM broadcast band, and even to the top of 
the amateur 160 meter band amigos !!!
Tip number one: Check your noise level, and try to find which are the 
radiofrequency noise generators that sorround your listening post. I 
remember many years ago when I first visited a point to point short wave 
communications system receiving station, that all the lamps they used 
were incandescent lamp bulbs... when I asked the Chief Engineer at the 
Prensa Latina news agency HF receiving station out in the countryside 
near Cuatro Caminos a small village southeast of Havana , he told me 
that fluorescent lamps were prohibited at the receiving site, because 
they generate a lot of Radio Frequency wide band noise.
He also added that the power line that provided electricity for the 
receiving site came by means of an underground three phase high voltage 
cable that was more than two kilometers long, so that no overhead power 
lines were within the vecinity of the antennas.
Of course that I am aware that the average low frequency Dxer cannot 
enjoy the benefits of such a specially built site, but you can certainly 
check carefully and find out, for example, how each of your home´s 
electrical distribution systems contributes to your low frequency bands 
noise level. Just by going to the circuit breakers at the entrance and 
disconnecting them one at a time, you may be able to find, for example 
that the breaker providing power to the living room , when disconnected, 
makes low frequency reception much better.... Something that later was 
traced to a fish water tank air pump... because the nice tropical fish 
aquarium was located right in the living room of the house. This was a 
real life experience for a Dxers Unlimited listener that sent a question 
to the ASK ARNIE section of the program asking how he could find out the 
source of a ticking sound that was making his reception on the low 
frequency bands very difficult , and even up to 10 megaHertz very 
annoying, because of a repetitive tick , that in this particular case 
was caused by the fish tank air pump !!!
By switching the circuit breakers one at a time, you may also find out 
that the older computer in the kids room , the one still running with a 
big CRT picture tube monitor is a terrible noise generator... a problem 
that can be solved by changing to an LCD monitor, but be aware , that it 
MUST be an LCD monitor,because the PLASMA displays are even worse noise 
generators than the old picture tubes used by the early computer monitors.
Next tip: This will require a small AM broadcast band receiver and a 
pair of good quality headphones...The next step is to go all around your 
home with all the lights ON, and put the small portable radio near each 
lamp, while it is tuned to an empty frequency at the low end of the AM 
broadcast band. As many Dxers Unlimited listeners have learned in the 
past, because this is not the first time that I explain this procedure 
in the program, well, this easy technique will quickly point at the 
noisy lamps...
With the compact fluorescent light bulbs now in use all around the world 
to save energy and reduce CO2 pollution , this is particularly important 
, and let me add amigos, that ¨¨ Not all compact fluorescent light bulbs 
are created equal¨¨ If you realize what I mean... The fact is that all 
radio hobby enthusiasts must learn which are the CFL´s compact 
fluorescent lamps that make less radio frequency noise, and to your 
advantage , there is the coincidence that the ones that generate less 
noise are usually the highest quality CFL´s , although I must add that 
they are also usually the most expensive too..
The next tip is also related to the way your home is illuminated, and it 
may be considered by some really dyed in the wool low frequency Dxers an 
essential step if you really want to reduce the local noise level... Try 
to start installing Light Emitting Diode Lamps... but be very careful, 
because some commercially built LED lamps are terrible noise generators 
too...
The reason that some of those super energy saver LED lamps generate 
noise, is that they used a switching mode power supply that sends down 
the drain any advantage that the low voltage light emitting diodes offer 
in contrast to the compact fluorescent lamps.
So, before buying LED light bulbs that can be plugged directly to 
replace incandescent or CFL bulbs, check that they are not using a 
switched mode power supply...
Some radio amateurs that have acquired all along their ham radio careers 
the ability to homebrew equipment, have built very nice arrays of white 
light emitting diodes that are powered from linear power supplies and so 
provide excellent illumination, no flicker , and no noise...
Just recently, a friend that visited here gave me several white light 
emitting diodes, and I decided to use them for making a lamp that is now 
located at my listening post and amateur radio station operating 
position, with excellent results... Although the Compact 15 watt 
fluorescent lamp that I used there was not very noisy, my sensitive 
broadcast band DX receiver could pick up the background noise that could 
only be suppressed by switching OFF the CFL lamp.
With the new white LED array of six diodes, the noise level is ZERO !!!
Well amigos, the topic of low frequency Dxing is so fascinating that it 
seems like it would require more time alloted to it during upcoming 
Dxers Unlimited programs.. You may want to provide me with feedback 
about today´s tips for reducing the RF noise level at your home , and 
also tell me if you have any question related to finding noise sources 
and trying to wipe them out !!!
...............
Si amigos, yes my friends, zero sunspots one day after the other, an 
amazingly low monthly sunspot count for July, and August is moving along 
the same line, but despite the minimum solar activity, radio amateurs 
continue to enjoy the hobby by traveling to remote DX locations and 
usually combining nice vacations with giving to fellow hams the 
opportunity to work new and usually rare prefixes...
Stay here until the end of the program because as ALWAYS when I am in 
Havana, at the end of the show, have your tape recorder ready for Arnie 
Coro's Dxers Unlimited's HF plus 6 meters propagation update and 
forecast , a practical guide for optimizing the enjoyment of your radio 
hobby , be it short wave listening or amateur radio, or any other of the 
more than 83 ways we can enjoy radio !!!
Here are is now one of the most recent Dx expeditions soon to be on the 
air...
The Principality of Monaco, with the ITU Prefix 3A will be on the air 
thanks to Patrice, a french amateur that will operate his Dxpedition 
with the callsign 3A stroke F5RBB starting on the first of September and 
for 10 days. Patrice will be on the air on 40, 20, 15 and 10 meters and 
his QSL information is via his home call via direct or trough the French 
QSL bureau.
He will provide a nice opportunity for newcomers to the hobby to work 
Monaco for the first time.
And now as always at the end of the program here is our HF and low band 
VHF propagation update and forecast. Solar activity expected to continue 
at baseline levels with solar flux not higher than 70, expect noise 
levels on the low frequencies up to 10 megaHertz to continue high during 
the late afternoon and early evening local time ,due to summer 
thunderstorm activity.
Best time for long haul DX continues to be starting at around 2 hours 
before sunrise and just a brief period after sunrise. See you all at the 
mid week edition of the program amigos, and don´t forget to send your 
signal reports and comments to inforhc at enet dot cu or Via Air mail to 
Arnie Coro, Radio Havana Cuba, Havana . Cuba
--
Posted By Arnaldo Coro to Dxers Unlimited 
<http://dxersunlimited.blogspot.com/2008/08/dxers-unlimiteds-weekend-edition-23-24.html> 
at 8/23/2008 10:40:00 PM
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