Re: [HCDX] Dxers Unlimited's weekend edition script for 27-28 January

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

Dxers Unlimited
Dxers Unlimited weekend edition for January 27-28 UTC
By Arnie Coro
Radio amateur CO2KK



Hi amigos radioaficionados around the world and in space! Welcome to the 
weekend edition of Dxers Unlimited reaching you when solar activity is 
still at really very low ebb… I am Arnie Coro, radio amateur CO2KK and 
here is item one of today’s program, solar scientists continue to 
scratch their heads about cycle 23’s final months…and there are 
conflicting news about the possibility that solar minimum is already 
behind us… yes , you heard it right, some recent statistical analysis 
could be interpreted as the first signs of a solar minimum that has 
already happened while some researchers still believe  that we may see a 
rather extended tail end of cycle 23, while others insist it  over by now.
Another school of thought continues to underscore the very high 
probability that upcoming solar cycle 24 is going to be a record 
breaker, even capable of matching the super cycle 19 that sent the 
average monthly sunspot count up to two hundred and seven.
For us radio hobby people, a super solar cycle, with a very high average 
sunspot count will also mean many solar flares and geomagnetic storms 
too !!! Now, we must just wait and see what’s going to happen during the 
next year and a half or so, when it would be possible to have a fairly 
good knowledge of the early phase of cycle 24…
Item two: The most popular amateur radio band around the world continues 
to be two meters, spanning in some parts of the world from 144 to 146 
megaHertz, while in other areas amateurs are assigned two more 
megahertz, so the band in those parts of the world goes from 144 to 148 
megaHertz as it happens in North America. Two meters is very popular 
because with very simple equipment and low cost antenna systems, radio 
amateurs are able to communicate locally and even at longer distances 
when propagation conditions are good and they may even use amateur 
satellites that have two meters uplinks or downlinks. But the two meters 
band is not only a good place for FM voice mode communications. Amateur 
operators can make very  good use of existing satellites, and also enjoy 
very sophisticated communications modes, like sending signals of high 
power transmitters to the Moon, using it as a passive reflector as part 
of an Earth – Moon – Earth or EME link.
I have made several two way amateur radio contacts using the Earth –Moon 
- Earth or EME mode while running at CO2KK, my ham radio station not too 
much power output and a pair of small size Yagi antennas.
But, fully equipped EME capable stations use huge antenna arrays, high 
power transmitters of up to the maximum legal power authorized to 
amateur operators and extremely low noise signal preamplifiers… EME is 
one of the more than 79 ways that you can enjoy our wonderful hobby… 
yours and mine: RADIO !!!
Amigos, Dxers Unlimited’s weekend edition will continue in just a few 
seconds… I am Arnie Coro in Havana, stay tuned or connected to our server:

……..

Si amigos, you are listening to Radio Havana Cuba, the name of the show 
is Dxers Unlimited, and as always its my pleasure to share with you this 
on the air and on the web time devoted to this wonderful hobby “RADIO” 
here is our next item, the most popular section of the show “ASK ARNIE 
“answering listeners questions as fast as they come in via e-mail sent 
to arnie@xxxxxxxxx
Today’s number one question: came from the USA, from Southern 
California, listener Adonis asks if he can adapt an FM band Yagi antenna 
that is sold at a popular electronics retailer outlet near his home, so 
that the antenna will work on the 2 meters amateur band… And amigo 
Adonis, the answer is YES… it can be done, and as a matter of fact, you 
will end up with a very nice looking 2 meters band antenna, at a much 
lower cost than if you try to homebrew one by buying materials at a 
hardware store. The typical FM band 5 or 6 elements YAGI antenna has a 
boom length that provides more than enough space for a 6 to 7 element 2 
meter band Yagi, and the length of the elements allow you to cut them to 
the segment of two meters where you want to operate.
After buying the commercial FM broadcast band YAGI, you must
proceed to carefully measure each element and write down the result of 
the measurement.
You will find that as in any typical Yagi parasitic array, the elements 
lengths go from the longest one, the reflector, that will be very near a 
half wavelength at the operating frequency, to the shortest one , the 
last director, that will be much shorter than a half wavelength.
The FM band Yagi will probably be cut for a frequency around 100 
megaHertz, because that is roughly the center of the FM broadcast band 
that spans from 88 to 108 megaHertz, and that means that the longest 
element of your commercially built Yagi will be very near 1. 5 meters 
long, that is almost 5 feet long.
The second step required for converting a commercial FM band Yagi for 
the amateur 2 meters band is to decide to which segment of two meters 
you want new antenna to be optimized. For example you may enjoy talking 
to friends on repeaters located in the upper two megahertz of the 2 
meters band, from 146 to 148 megaHertz, so you may want then to optimize 
your YAGI for a center frequency of 147 megaHertz, which is not exactly 
the optimum way of doing it, but that in actual practice works quite well.
The third step is to use any of the available freeware programs that 
calculate YAGI VHF antennas, and run it with the 147 megaHertz center 
frequency design target.
Those programs generate several outputs: they will give you the length 
of each element; how the elements are spaced along the antenna’s support 
boom and also you will be able to see the actual theoretical horizontal 
and vertical radiation patterns.
Your fourth step requires the use of a measuring tape and a hacksaw, to 
cut the elements to the required lengths, following the data provided by 
the YAGI antenna calculating software.
Fifth step, requires using an electric drill to carefully locate and 
drill the holes where the elements will be fixed to the boom, that will 
not be the same ones used for fitting the elements to the original FM 
Yagi antenna
The sixth and almost last step requires a decision on your part, it you 
want to operate using horizontal or vertical polarization. Using 
horizontal polarization as needed for operating on CW and single side 
band modes at the lower edge of two meters needs no change to be done to 
the boom, but if you want to use vertical polarization, as required for 
FM voice and packet radio modes, then you must drill new holes so that 
the antenna may be installed for vertical polarization, in other words 
the support clamp will be at 90 degrees from the original position used 
for receiving FM broadcast band horizontally polarized signals..
The last step is to adjust the antenna for minimum standing wave ratio, 
and for doing this you will need a VHF standing wave ratio meter, and 
the help of an experienced radio amateur that has adjusted Yagi antennas 
before… Take good notes of what you do, write them down, so that in the 
future you will be able to adjust other antennas all by yourself…
Amigo Adonis, I am sure that you will be able to find at a local radio 
club someone willing to help you with your antenna conversion project… 
And don’t forget that a YAGI with 5, 6 or 7 elements is a highly 
directional antenna that requires the use of an antenna rotor if you 
want to have around the compass coverage!!!

…….

QSL , QSL , QSL on the air from Havana to the many Dxers Unlimited 
listeners around the world that have written during the past several 
weeks reporting good reception of our 6180 kiloHertz English language 
program heard between 05 and 07 UTC. The antenna we are using on 6i80 
kiloHertz is our new Central North America curtain array, it is 
technically speaking according to ITU definitions an HR 4, 4 , 0.8 
system, that meaning that it has 4 sets of dipoles set in four rows and 
four columns a configuration that provides close to 20 decibels of 
effective antenna gain over a half wave dipole placed at the center of 
the array. The new antenna is also getting reports from other parts of 
the world too, where listeners that wake up very early in the morning 
are picking up the last hour of the English program between 06 and 07 
UTC. If you are picking up Radio Havana Cuba on 6180 kiloHertz in 
English from 00 to 05 UTC,you are listening to the same antenna and 
transmitter combination too.
Item six: For more than fifty years I have been fascinated with my 
father’s 14teenth birthday present… a regenerative radio receiver kit 
that he was sure I was going to be able to assemble without any help, as 
dad told my uncle Armando during the birthday party.. that little radio, 
assembled breadboard fashion is still working after half a century have 
passed, and it has also served as the prototype for many other clones 
that I have helped to build all along these years. The latest version of 
my BIRTHDAY Regenerative is a bit more sophisticated than the original 
one, and works beautifully with the sets of plug in coils that its proud 
owner my now almost twelve year old grandson has built so far… As 
batteries are hard to come by locally and very expensive, this version 
of Arnie’s Birthday Regenerative uses a very safe 24 volts DC supply to 
power Arnie Coro the Fourth wonderful new toy!!!!
If you want to learn more about my BIRTHDAY Regenerative receiver, just 
drop me an e-mail to arnie@xxxxxx or a postcard to Arnie Coro, Radio 
Havana Cuba, Havana , Cuba asking me to send you the Birthday 
Regenerative receiver information package…
And now, as always at the end of the show, here is Arnie Coro’s Dxers 
Unlimited, HF plus low band VHF propagation update and forecast…Let’s 
begin with the actual sunspot count that on Friday was 11,solar flux was 
near 80 units and the A index Saturday morning local time in Havana, 
that is at around 13 hours UTC was a nice and low ONE…, with the maximum 
useable frequency curve going as high as 33 megaHertz over parts of 
Africa, a good indication of the not too bad  propagation we are 
enjoying despite the very low solar activity. The BAD news is that we 
may soon see yet another geomagnetic disturbance as the solar wind is 
bringing in a much higher than usual proton count that is expected to 
increase by Monday unleashing a possible geomagneti storm at high 
latitudes… Keep time available for DXing from about an hour before your 
local sunset to three or four hours after sunset, and enjoy a second 
propagation peak starting at around two hours before sunrise, and 
extending no more than an hour after sunrise…
  And don’t forget to send me your comments about this program, signal 
reports QSL requests and radio hobby related questions to arnie@xxxxxx, 
or VIA AIR MAIL to Arnie Coro, Radio Havana Cuba, and Havana, Cuba


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