Prof. Arnaldo Coro Antich
Radio Havana Cuba
Dxers Unlimited weekend edition for Sunday 7 May 2017
By Arnie Coro
radio amateur CO2KK
Hola mis amigos radioaficionados that are now listening to the weekend edition of Dxers Unlimited...I am Arnaldo, Arnie, Coro radio amateur CO2KK, your host here at the one and only radio hobby program on the air and on the web providing coverage to every one of the more than 90 ways of enjoying this wonderful hobby....RADIO. A quick check shows that more and more radio amateurs are using sophisticated digital communications modes that require the use of really high performance computers... Other ham operators that run older machines still have the option to use the easy digital mode... PSK31 and its higher speed versions like PSK63 and PSK125... and here is today's program first topic...Radio amateurs in the Caribbean region, Central America, Mexico and the Southern United States are getting ready to deal with the upcoming Tropical Hurricane Season, due to start on the first day of June, although this year a very rare tropical cyclone developed out of season, surprising scientists that carefully tracked the storm... So far I have not heard about the season's forecast that is published every year ahead of the start of the six months long period that spans from the first of June to the end of November... Preparations for providing emergency communications is at the top of the list of activities by Cuban radio clubs .
Item two: Amazing two way amateur radio contacts on the 80 and 40 meters bands are happening almost every day while using power outputs into the antennas of one Watt of even less. Minimalist transceivers that use the output power transistor as the receiver input product detector have shown that when propagation conditions are normal or above normal, two way contacts can be made using such low power rigs that follow the design criteria of the minimalist PIXIE transceivers . Si amigos, yes my friends, a low parts count little transmit and receive capable home assembled rig when connected to an efficient antenna will be able to establish long distance contacts ...
Item three: Answering a question sent by listeners from Australia... that wanted to know more about the DRM Digital Radio Mondiale system... Yes amigos, it is exactly what is happening, what continues stop to a standstill the introduction of DRM is certainly be the lack of low and medium cost receivers capable of picking up DRM signals And yes, we have confirmed from two independent source that about an integrated circuit capable of demodulating all possible transmission modes, including standard AM, FM, and several of the already on the air digital radio modes, like DRM, the IBOC or HD Radio and all different DAB modes....is expected to the licensed for production by several IC manufacturers . As expected massive production of this new digital integrated circuit that automatically detects the modulation mode in use , producing clear audio output, could be the much needed breakthrough every one is expecting in order to introduce the most efficient digital modes at a worldwide scale....
Now from Dxers Unlimited's weekend edition... a short form solar activity update.... The Sun is once again going through another period of very low activity, but for the past several days we have seen sunspots every day...
Each of the weekly solar and geomagnetic indicators that are tracked were lower this week. Average daily sunspot number dropped 10.6 points to 25.1, and average daily solar flux was 4.5 points lower than the previous week at 76.9.
It is comforting to see though that we have not witnessed a day with 0 sunspots since April 17. Average planetary and mid-latitude A index were both 5.6, down from the previous week which had planetary A index at 26.4 and mid-latitude at 18.4. The A index is expected to remain quiet until May 17-20.
Stand by now for a few seconds as we go to a break for a station ID. I am Arnie Coro in La Habana Cuba
short musical intercut
This is Radio Havana Cuba, the name of the show is Dxers Unlimited, and yes amigos we are very proud of having helped many short wave listeners around the world learn about the existence of amateur radio, leading the way for many of them to now own and operate their own amateur radio service stations to communicate across town on two meters or half way around the world on the most used DX band... 20 meters.... By the way, I enjoy a lot calling CQ DX on 14 060 kiloHertz using slow speed hand sent Morse Code Radiotelegraphy while running 5 Watts or less into a wire antenna that was made from recycled wire coming from a burnt out power transformer primary winding. The three insulators required were made using poliethilene flexible garden hose stock of three quarters of an inch diameter.... That is a low cost antenna by all comparisons... because it is fed using a two wires balanced transmission line also made from the same recycled wire and insulators for the ladder type feed line cut from the same length of poliethilene garden hose. As I have said it here many times.... amateur radio need not be an expensive hobby at all, and my dipole antenna is just another example... It is cut as a full size 60 meters band half wave dipole, and tunes easily from 80 meters all the way up to the 10 meters band, and let me add that using a second antenna tuner especially made for the six meters band the antenna works nicely on the 50 megaHertz band too...
5 watts CW on the 20 meters QRP calling frequency 14060 kiloHertz has made possible contacts as far away as New Zealand under good propagation conditions, and as expected many replies to my CQ calls from CO2KK are received from the first skip zone of 20 meters that spans for around two to three thousand kilometers away from La Habana, Cuba where my station is located. Whenever very short skip is present on 20 meters , I just move to the six meters band and start calling CQ DX, because the very short skip on 20 meters is a very good indicator of possible sporadic E openings on six meters. Let me insist on something said earlier this week....Amateur radio operators having stations capable of operating on the 10 and 6 meter bands will be able to make many DX contacts on those two bands during the summer Sporadic E season that is now starting... But.... the real challenge brought by Sporadic E layer events is that so far they have proven to be impossible to predict... there is no known forecasting method that can tell in advance when one of such super density sporadic E layer patches starts suddenly bringing in DX signals for periods as short as a few minutes or maybe even hours and then suddenly just vanish...And let me also insist on the fact that for 6 meters band operators the sporadic E events make possible working DX stations several hundreds of miles away, with the first skip zone area coming after a zone of no signals... There is also the possibility of double and triple hop skip signals when two or three patches of high density sporadic E clouds align themselves properly...
And now at the end of the program here is our propagation update and forecast for the next several days--- solar activity still at very low levels, just a few weak sunspots active regions in sight Saturday morning local time here in Havana.... 14 hours UTC... when I was typing the script of this program you are listening to right now. Be on the look out for more sporadic E openings... it is now clear that the late spring and summer E skip season is well under way...AMIGOS please don't forget to set aside a little time to send me a signal report and your most appreciated comments and radio hobby related questions to Dxers Unlimited. Send mail to inforhc at enet dot cu ... Via Air Mail to Arnie Coro, Radio Havana Cuba, Havana , Cuba