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Re: [HCDX] Dxers Unlimited's weekend edition for 5-6 May NOW E Skip season in full swing !!!
Radio Havana Cuba
Dxers Unlimited
Dxers Unlimited’s weekend edition for May 5 – 6 2007
By Arnie Coro
Radio amateur CO2KK
Hi amigos radioaficionados around the world and in space orbit… I am
Arnaldo,Arnie, Coro, your host here at the weekend edition of Dxers
Unlimited, join me for about seventeen minutes of all radio hobby
related topics… Here our number one here today: Sporadic E season now in
full swing all over the Northern Hemisphere. Friday morning TV signals
from Central America, the Caribbean and the Southern USA were coming in
here in Havana for several hours, and also the 6 meters band opened up
for single hop skip… Several nice signals from amateur radio beacons
both on 10 and 6 meters served very well to provide me with a good idea
of how the Sporadic E clouds were moving around. Expect more E skip DX
during the rest of the weekend and also for the whole next week amigos
!!! Keep those 6 meter band transceivers scanning from 50 dot zero zero
to 50 dot three hundred, where most of the DX activity concentrates on
the 6 meters band, and if you happen to own one of those nice little
Radio Shack or UNIDEN HTX 100 or HTX10 10 meters band transceiver, this
is the time to keep it on monitoring the band for Sporadic E skip DX…
AND, if you don’t have an antenna installed for your 10 meters band
transceiver, go ahead and set up a half wave dipole and connect it to
your 10 meters band transceiver so that you can enjoy the short skip
season that will last until the end of July…
Item two:Big sunspot 953 now loosing steam, but still capable of class C
and even an isolated Class M solar flare… No more big sunspots visible,
so next week, is nothing new happens, we will return back to the zero
sunspot count for several consecutive days…
Item three: Light emitting diodes capable of replacing the compact
fluorescent light bulbs are now available… No, I am not talking about
clusters of L E Dees… I am telling you about huge semiconductor chips
that emit ultraviolet light that is then converted into the visible
spectrum by means of certain chemicals… At least one automobile maker is
now installing these new high power white light LEDees as the primary
headlamps main beams… an outstanding achievement by all standards… Now
you may ask me how this news connects with radio, and the answer is that
soon you may be able to replace all the compact fluorescent light bulbs
with super bright high efficiency LEDees , and by doing so keep away, at
least from your home the radio frequency noise generated by the
transistorized oscillators that power the compact fluorescents…
More radio hobby related information follows in a few seconds , after a
short break… I am Arnie Coro, in Havana…
……
This is Radio Havana Cuba, the name of the show is Dxers Unlimited, and
yes we are now 46 years old amigos… On May first our station celebrated
its 46th anniversary… And among the recent features we have a new easier
to remember web address, a new fast URL… it’s very simple, just type
rhc.cu, and you will be connected to our website… Now here is item four:
In a few days a great number of Cuban amateur radio operators will be
participating in our annual Meteoro weather emergency drill… It takes a
whole weekend, and serves the very useful purpose of testing all the
radios, antennas, computers, and of course the emergency readiness of
our radio clubs all along the Cuban archipelago, as we all get ready for
the Atlantic Tropical Hurricane Season that starts on the first day of June.
Among this year’s highlights will be the first actual use of our new low
cost almost 6 dB gain over a dipole omnidirectional two meter band
antennas, that have proven to provide much stronger signals than the up
to now classic TV twin lead J pole antennas we have used.
AND PLEASE REMEMBER… that one of the main reasons that amateur radio
enjoys the exclusive use of very valuable radio frequency spectrum space
is the fact that our wonderful and unique hobby is able to provide
emergency communications even under the most difficult and demanding
circumstances, when professional telecommunications overload or simply
collapse ! So please support your local radio club emergency efforts,
participate as part of the emergency drills, and keep all your emergency
equipment ready to go at anytime it may be needed…
For those of you in areas where tornadoes are frequent visitors, it is
very important to have batteries, emergency lights, drinking water and
if possible more than one hand held transceiver always ready !!
……..
Si amigos, yes my friends, oui mes amis… short wave listening is a nice
aspect of the radio hobby that is still enjoyed by many of us... Some
people listen at least once or twice a week to their favorite high power
stations, and pick up certain programs that they enjoy, while others
keeping with the tradition, tune in every day looking for weak signals
and trying to find new stations. You may find out that even today , with
the extremely high levels of radio frequency interference generated by
computers and TV sets, some of the big international short wave stations
still manage to deliver signals that can be heard above the noise even
with the portable radio’s telescopic whips, but it is always a very good
idea to add an external antenna to your short wave radio, even though it
may be an indoor antenna, it certainly will improve reception. I have
had very good results with a magnetic loop tuneable antenna built using
standard coaxial cable and a PVC pipe support. The antenna is also
highly directional , so it helps to cancel nearby noise sources, a very
useful feature indeed… Professional magnetic loops with motorized remote
tuning controls cost a lot of money, but a homebrew manually operated
version , like my ML- Dash 3, the latest version of this simple easy to
build antenna that improves short wave reception in a very significant
way… If you want to know more about the ML Dash 3 antenna, just send me
an e-mail to arnie@xxxxxx, again, arnie@xxxxxx , and I will send you the
Magnetic Receiving Loop Info Pack… with many illustrations and details
that will give you a very good idea on how these antennas are built. All
I can say that here we are able to make an ML Dash 3 is about three
hours , and that they look really nice, as a matter of fact, the antenna
can be considered a piece of modern abstract art that will blend nicely
with the interior decoration of your living room amigos
Don’t worry about the cost… it’s about the least expensive practical
efficient antenna that you can build or buy… and as someone that
recently visited my amateur radio station said, it is hard to understand
why it is not sold by the main antenna manufacturers around the world. I
keep an ML Dash 3 tuneable magnetic loop antenna that was designed to
cover from 5 to 25 megaHertz right next to my amateur radio station
second receiver, a Russian R-250 M2, that when connected to the ML Dash
3 is able to provide clear signals when the transceiver connected to the
external fan dipole antenna can not bring them in due to the high
prevalent noise levels… By turning the ML-Dash 3 I am able to optimize
the signal to noise ratio and also benefit from the extremely high Q of
this antenna, that also acts as a front end filter…
One of the frequent visitors to CO2KK, amigo Reynaldo CO2IRG, who
recently passed the first class amateur radio operator test and upgraded
his callsign from CM2IRG to the present CO2IRG, commented that the ML
Dash 3 antenna design could also be optimized , by changing the variable
tuning capacitor , so that it could serve as a standby emergency
transmitting antenna, something that is perfectly possible, although the
antenna must be kept well away from the operator , because of the very
high intensity nearby radio frequency field that it generates.
Yes amigos, the ML-Dash 3 a compact, low cost , fully tuneable and easy
to homebrew magnetic loop antenna, made from a length of RG213 or RG8
coaxial cable, PVC pipe, an air spaced variable capacitor, and a short
length of RG58 U cable terminated in the RF connector that your receiver
uses… It will take you about three hours to complete, and I can assure
you that it will improve short wave reception of any radio receiver to
which it is connected… And the only inconvenience that I see when using
the ML Dash 3 magnetic loop is the fact that it must be retuned, yes,
you must peak the tuning for maximum signal every time you change the
operating frequency, because it is certainly a very narrow band antenna
system !!!
What may be thought to be like a drawback, will be, in actual practice
an asset , because the ML Dash 3 antenna acts as a highly effective
front end radio frequency high Q filter, that will improve reception of
even the very low cost short wave receivers, and all my tests here, with
professional radios, show that the ML Dash 3 antenna is about the best
ever indoor antenna ever used at CO2KK , my amateur radio station where
I also have installed a short wave and a medium wave AM broadcast band
listening post.
……..
ASK ARNIE , the most popular section of Dxers Unlimited coming almost at
the end of this weekend edition of the show… Today’s question sent in by
listener Oleg from Ukraine.. He is picking up our 12000 kiloHertz
Spanish language program to North America from 11 to 15 hours UTC… Oleg
is asking in his e-mail sent to arnie@xxxxxx if it is possible to
upgrade a short wave portable radio receiver by building a converter, so
that the radio will then be operated as a double conversion receiver.
Amigo Oleg, you are absolutely right… a typical consumer short wave
radio like the medium sized portables can be improved dramatically if
you homebrew a crystal controlled converter, and then use the radio as a
tuneable intermediate frequency. The converter can be designed in many
different ways, and you can do a lot of experiments with it. I have
already sent via e-mail , the circuit diagrams of several converters
that can be built using parts that are not that difficult to find.
Just to give you an idea Oleg, I recently tested a three transistors
converter with my Grundig Eton FR200 portable , using the Grundig as a
tuneable IF in the range from 3.2 to 5.2 megaHertz , with the converter
input from 14 to 16 megaHertz. As I had already added a BFO to the FR200
Recycle Power radio, using the converter I am able to listen to radio
amateurs on the 20 meters band and also to international short wave
broadcast stations on the 15 megaHertz or 19 meters band without the
problems that are typical of a single conversion receiver working above
about 8 megaHertz or so when using an intermediate frequency around 400
to 500 kiloHertz, as is the case of the FR200…
More about this short wave frequency converter to upgrade low cost
receivers in an upcoming edition of Dxers Unlimited, and now, as always
at the end of the program here is Arnie Coro’s Dxers Unlimited HF plus
low band VHF propagation update and forecast … Solar activity will be
very low for the next three days, and the geomagnetic activity will also
be at quiet levels… Expect daytime maximum useable F2 layer frequencies
to reach briefly up to 22 megaHertz , and also Sporadic E layer openings
becoming more and more frequent with signals on frequencies as high as
the 2 meters or 144 to 148 megaHertz amateur band propagating at the
peak of the sporadic E events… Join me next Tuesday and Wednesday UTC
days for the mid week edition of Dxers Unlimited and don’t forget to set
aside a little of your time to send me a signal report and your comments
about today’s program… send mail to arnie@xxxxxx or VIA AIR MAIL to
Arnie Coro, Radio Havana Cuba, Havana, Cuba
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