Radio Havana Cuba
Dxers Unlimited
Dxers Unlimited's mid week edition for 28-29 March 2006
By Arnie Coro
Radio amateur CO2KK

Hi amigos radioaficionados ! With our traditional salute to radio hobby
enthusiasts around the world, Dxers Unlimited's midweek edition will bring
you about sixteen minutes of all radio hobby related information.. I am
Arnie Coro, radio amateur CO2KK, your host here in Havana, the sunny capital
of Cuba now ready for item one: Sunspot count once again ZERO, and no
coronal holes in sight, so expect very low ionospheric absorption during
next three days. Solar flux hitting bottom low figures of around 75 units.
Item two: Power for handheld transceivers during emergencies is something
really critical, that's why operating during emergencies requires a lot of
discipline and control , so that the radio will be able to go on the air
when it is really needed. Emergency operators that talk a lot have to be
taught how to keep silent, and also how to keep transmissions very short to
save precious battery energy.Crank up generators and flexible solar panels
should be also considered as very serious options for portable emergency
stations that, by the way, must be ready to be taken along by the operator
to the remote site where her or his communications skills are required. And
don't forget those moderate gain antennas too, as they will be more
efficient than the handie-talkie's rubber duck and thus help to save battery
power.
High speed data links, using notebook computers or PDA's will certainly help
to save energy too, but they do require a lot of training, special equipment
and the proper know how to operate .
Dxers Unlimited's mid week edition is coming to you from Havana..

Si amigos, you radio is tuned or your computer is connected to Radio Havana
Cuba, then name of the show is Dxers Unlimited, and it's on the air twice
weekly with the most up to date short wave  propagation information at the
end of the program.. Now here is item two: Trans equatorial propagation on 6
meters is spanning from the Caribbean to Brazil,and even farther up North
when conditions are really good.
6 meter operators are having a good time making nice two way contacts using
the spring equinox trans equatorial propagation peak.
Item three: ASK ARNIE, our most popular section of this show will be
answering on the air and via e-mail several questions today. First one, sent
by several Canadian listeners, they want to know if it is true or not that
Sporadic E propagation is better below latitude 40 North, and especially
better below 30 degrees North:
Answer; YES. all statistical analysis available confirm that stations
operating at latitudes between 10 degrees and 30 degrees North see a lot
more sporadic E events and that they seem to last longer than those whose
QTH is located above that latitude. Question number two: Also came from
Canada, where Dxers Unlimited has a very faithful listenership. The question
> Arnie, is it true or not that some trade marks of energy saver fluorescent
light bulbs are noisier than others. ANSWER: That's absolutely true, and
there seems to be a very clear relation between the price of such energy
saver lightbulbs and how quiet they may be from a radio frequency noise
point of view.
The cheaper bulbs tested at several  HF stations, have ALWAYS produced more
radio frequency noise than the more expensive ones, but even among those
that are more expensive, certain trade marks are quieter than others, an
indication that radio frequency noise suppression is very dependent on the
design of the energy saver lightbulb electronics.
Some of them have better radio frequency bypassing than others, and that
reduces the noise getting into the power line circuits of your house. But
some of the noise generated by the power oscillators of the energy saver
lightbulbs is also radiated, and that power is not on a single frequency..
So that's yet another problem. The frequency of oscillation is different
according to the manufacturer, and my tests show that it changes slightly
also from lamp to lamp !!!
Installing radio frequency noise suppressing ferrite chokes and ceramic
bypass capacitors is a possible solution , but it is often very difficult to
put in actual practice, except when you are dealing with tabletop lamps that
can easily be opened up and the ferrite chokes and disk ceramics fitted
inside between the energy saver lightbulb and the power line connection.
Nevertheless, installing energy savers all around the house is a very good
idea to help reduce the electricity bills and also it is good for Mother
Earth, as less heat and CO2 gas is generated when using these lamps than
when you are using standard incandescent lightbulbs.
BUT, again, at some specific locations, especially near your radio receivers
and transceivers, they may cause a lot of noise that will certainly
interfere with long wave, medium wave and short wave reception. Your
comments about your experiences with the different brands or trade marks of
energy saving electronic fluorescent lightbulbs , designed to directly
replace conventional incandescent bulbs are invited. Send them directly to
arnie@rhc.cu, again, arnie@rhc.cu, or VIA AIR MAIL to Arnie Coro, Radio
Havana Cuba, Havana, Cuba, and I am sure that many Dxers Unlimited's
listeners around the world will be very happy to learn from your experiences
, and that they will then buy the energy savers that generate less noise of
them all !!!
...
Si amigos, this is our mid week edition, and it's certainly nice to share
with you this time devoted to the promotion and development of our wonderful
hobby , the one and only that is never boring and always
presenting a challenge to your skills and your knowledge.
For example, how many of you Dxers Unlimited's listeners that are also
amateur radio operators like yours truly,  ended this past weekend totally
exhausted after the WPX Prefix contest ? And how many of you worked so many
new stations that have boosted your DXCC ratings a lot ? Amateur radio
contests are a great challenge to the participants, who must develop really
extraordinary operating skills in order to be among the winners. Operating
amateur radio contests is one of the more thatn 77 ways that you and I enjoy
this wonderful radio hobby.
Item six: Last Saturday someone knocked at my door and handed me a big
circuit board full of electronic components. Coro , he said , just found
this at the dumpster in my workplace, and thought it would be useful for
your amateur radio students training program. and sure it was.. I gave a big
thank you to Miguel my neighbor and began to make an inventory of all the
parts soldered to the huge circuit board.
It was obviously part of an obsolete mainframe computer, and the quality of
the components was outstanding. I spent about an hour and a half Sunday
morning in a most relaxing desoldering exercise, that ended up with 48 NPN
signal transistors, as two of the 50 original ones broke a leg when
desoldering, 96 disk ceramic capacitors, 64 electrolytic capacitors and a
couple of hundred resistors. Enough electronic components to assemble many
new projects for the radio club's newcomers to the hobby. Now, I will have
to test each component , one by one, and put them into an organized storage
system, so that they will be ready when the next training course for people
interested in becoming radio amateur operators begins by mid April. Recycled
electronic components when properly desoldered and tested are usually in a
like new condition, and may be used in any project with total confidence.
You will certainly save a lot of money, Mother Nature will say thank you for
not receiving the impact of the chemicals and metals involved in making
those components and you will have two periods of enjoyment , first when
removing and
testing the parts, and second when putting them into the new circuits that
you are building . And now another tip for people like you looking for
recycling opportunities.
Computer Dial-Up MODEMS have very nice audio amplifier IC's , lots of 3.5
millimeters jacks, light emitting diodes and even small loudspeakers, and
DSL , cable modems and satellite links are sending many dial-up modems into
early retirement. so look around for them, as yet another source of ZERO
COST parts for your projects, including the plastic cases of external modems
that when properly adapted provide ideal small cabinets for your projects
!!!
...

This is Dxers Unlimited's mid week edition, and here is our antenna topics
section. today I will tell you more about experiments with the
Large diameter dipoles, with high capacitance end loading sections.
The latest experiments here with a dipole made using twelve wires
around a 60 centimeter diameter , that about 2 feet, ring, connected to two
1meter or a bit more than 3 feet diameter disks at each end, show that when
this antenna has a length of just 3 meters or a bit less than 10 feet on
each side of the dipole, the system can be made to operate with good
efficiency even on the 40 meters or seven megahertz amateur band.On 30
meters , or 10 megaHertz the efficiency of this system is up to par with a
full size dipole that is 15 meters or almost 50 feet long.
It is certainly a heavy weight antenna by all standards, but you can design
the proper rigging to keep it up and running, and if you are really short of
rooftop space, this antenna is an excellent option for all bands from 7
megaHertz up, and certainly a very good performer
From 14 to 52 megaHertz.
If you want to know more about this latest wire cage wideband short
dipole, just send an e-mail to arnie@rhc.cu, and I will send you a
Table with all the right dimensions for making this nice antenna system that
doesn't require a ground plane to operate.
And now just before going QRT here is Arnie Coro's exclusive and not
copyrighted HF propagation update and forecast. Solar activity is very low,
and the geomagnetic field is expected to remain quiet for several days in a
row. Solar flux hovering at bottom low leves of 75 units and the A index
will also be very low during the next few days helping low band propagation
a lot, so AM medium wave band and Long Wave AM broadcast bands Dxers are
going to be able to pick up some very nice DX, and the same holds for 160
meters and 80 meters band amateur operators.
Hope to have you listening to the weekend edition of the program, and don't
forget that the few minutes it takes to send a signal report, and your
valuable opinions about the program will certainly help me to make a better
one next time we go on the air.
Send mail to arnie@rhc.cu and your AIR MAIL postcards and letters to Arnie Coro , Radio Havana Cuba, Havana, Cuba