Hi amigos radioaficionados … with our now traditional salute, we are saying hello to radio hobby enthusiasts around the world from sunny Havana, Cuba. I am Arnie Coro, radio amateur CO2KK, inviting youth to join me for about seventeen minutes of on the air and also on the web time, plus the now regular option of reading the scripts of this program by subscribing one of several Internet radio hobby mailing lists.
Here is today’s show first item…Another week of very little solar activity reported by scientists, who continue to wait for the expected increase in the number of sunspots from the new cycle. So far, the new sunspots are just missing, and the daily solar microwave flux continues to be at extremely low levels. Item two: Just a few days away from the spring equinox here in the Northern Hemisphere, and already we are seeing somewhat better propagation conditions especially just before sunrise and just after sunset local time. Item three: Cuban radio amateurs began the new training program during the weekend, at my local club, the Plaza Radio Club we had a very nice meeting and the group of newcomers to the hobby started to receive their lessons in electronics, rules and regulations, radio wave propagation and communications procedures. The training course is programmed to last until May and the radio amateur operator’s tests will take place in June.
The Radio Amateurs Academy as this program is known counts with experienced certified instructors selected among the nation’s first class operators, the ones that are on the air with the CO, the Charlie Oscar prefix. Cuba has four prefixes for its stations registered at the ITU, that include CL, used or the beginner’s license, the CM intermediate class amateurs , CO used for the first class licensees and the T4 prefix that is only assigned to special event stations.
More about our wonderful radio hobby here in Cuba and in the world after a short break for station ID… I am Arnie Coro, radio amateur CO2KK in Havana…stay with us amigos… I will be back in a few seconds…
Yes, you are listening to Radio Havana Cuba, and if the bad weather is keeping you at home, it’s good time to start tuning around for new stations. Amateur radio operators that are stranded at home due to bad weather enjoy working DX when there is no other choice but to wait until the weather clears. And now there is yet another incentive to go on the air… the new Clipperton Island DX expedition is on the air, with high hopes of making a good showing as the just finished Ducie Island expedition achieved.
Ham radio expeditions to put on the air remote places are a great incentive for Dxers and the dream of any devoted Dxers is always fixed at having the unique opportunity of taking part on one of the real prominent DX expedition. I remember way back in 1965, when a group of Cuban radio amateurs activated for the first time in many years the CO4, the Charlie Oscar 4 prefix , by putting on the air a station at a remote little island to the south east of the Isle of Youth, how a fascinating experience it was for the team , despite the many mosquitoes and one dangerous encounter with a big salt water alligator, a cayman, that enjoyed swimming swiftly between the small little islands , something we discovered many days after going out to swim at the beautiful deserted beach…
We made a large number of two way radio contacts using CW and phone, but at that time we had no digital modes equipment and taking to the Avalos key location radioteletype equipment was not possible. Another nice way of enjoying group activities is to take part of a station participating on a ham radio contest, a very demanding activity that will require for you to take a Monday and possibly Tuesday break after the contest weekend!!!
More than two and half million radio amateurs around the world enjoy communicating using their own equipment and antennas, sometimes from the most unique locations, like an Antarctic scientific expedition or the cockpit of an airliner cruising at thirty seven thousand feet, something that airline pilots that are also ham operators do more often than what you may think, because as a very good friend of mine that seats on the left hand seat of wide body jets likes to say… cruising at high altitudes over the world’s oceans can be really boring, due to the high degree of automation of modern aircraft !!! Aeronautical mobile, from a glider or a wide body jet is equally enjoyable and is one of the more than 80 ways that people enjoy amateur radio!!!
Yes amigos, we do QSL, we do verify well written and documented reception reports, something that is very easy to do, you will only need to send us an e-mail to arnie at rhc dot cu that includes the date, time, frequency, signal intensity and short description of the program content at the time you were listening. Of course that you can add whatever comments you may think will be useful to us, and that’s the way that Dxers Unlimited´s worldwide audience has helped to shape this show so that it will be attractive to the most diverse audiences, from dyed in the wool radio experimenters to the casual short wave listener that has just bought a small portable radio…
You can also send your signal reports , comments and ideas on how to improve our programs , as well as any radio hobby related questions VIA AIR MAIL to Arnie Coro, Radio Havana Cuba, Havana, CUBA… and now here is our next item of the mid week edition of Dxers Unlimited…
Our very popular technical topics section of the program now ranking third among the most favorite ones… ASK ARNIE is still la numero UNO, the most popular part of the show, closely followed by the HF and low band VHF propagation update and forecast, and then in third place is this one just starting now…
Technical topics that today will be discussing how radio amateur operators are collecting broken down microwave ovens, to salvage their high voltage power transformers. After several not too difficult to implement modifications that include the removal of the magnetic shunt devices, the typical microwave oven power transformer can be rather easily modified to become the heart of a high power linear amplifier power supply… The high voltage rectifier diodes salvaged also from microwave ovens are ideal for the job, but you must look to other sources in order to obtain the required high capacity high voltage filter capacitors. By the way, handling microwave oven power transformers is something that should only be done by persons that are really experienced about the safety measures required, because the high voltages involved can be lethal…
You will never want your hobby to be the way to death, so whenever working with high voltages, please follow all the safety measures and recommendations, because at voltages that can go as high as four thousand volts, you will usually make just one single and certainly fatal mistake. That is why high voltage power supplies that are homebrewed must be built with all the recommended protection measures, including safety interlocks and a crowbar assembly that short the output to ground when the door of the power supply is opened…
……This is Dxers Unlimited´s mid week edition coming to you from sunny Havana, where there are now fifteen radio clubs, one at every municipality of the City of Havana province… The Habana del Este Club is one of the more enthusiastic of them all, closely followed by La Lisa at the other end of the city and Cotorro at the extreme south east . Each of the radio clubs has encouraged among its member that they monitor what is known as an internal 2 meter frequency, that meaning a simplex channel that all members of each municipal club know well and keep a watch on them when they are at home or moving around with a handy talkie…
The internal frequencies have proven to be an asset because they help to develop local communications between radio amateurs that live in the same area. The City of Havana province has a flagship long range repeater, located at 500 feet above the street in downtown Havana, at the rooftop of the 35 stories high Habana Libre hotel, The 145.190 repeater can be accessed using handy talkies from locations that continue to amaze me. Of course that keeping the receiver of the repeater in good shape and the diplexer of the antenna system tuned properly helps to keep the sensitivity of the repeater station well below half a microvolt, an outstanding figure even for professional installations.
Many City of Havana radio amateurs have homebrewed a very simple portable antenna for the two meters band FM transceivers of handy talkies…something that help to access the long range repeater from much farther away distances than the ones possible with the radio’s factory built antennas.
QSL on the air, si amigos, QSL on the air to the many RHC listeners that have written to me asking for more information about Cuba’s AM and FM radio broadcasting stations…
So following the request, I will tell you today about one of the most widely heard AM stations from Central Cuba. It is the Santa Clara Radio Reloj station relay operating on 570 kilohertz running now a nice new 25 kilowatts solid state transmitter, after the old Tesla vacuum tube technology that served there for many years was finally taken off the air. Radio Reloj´s Santa Clara City relay station has a very nice 400 feet high antenna, with a very good ground system, and the reason that this low frequency channel was selected for Radio Reloj´s relay serving Villa Clara, Cienfuegos and Sancti Spiritus provinces was no other than the mountainous characteristics of most of the service area, where lower AM broadcast frequencies provide much better ground wave service than stations operating on the part of the band
above 800 kilohertz or so…
And now amigos, as always at the end of the program, here is as always and absolutely free, Arnie Coro´s HF plus low band VHF propagation update and forecast… Solar activity is expected to continue at very low levels, but the equal illumination of Planet Earth during the equinox will improve short wave propagation during the next three to five weeks amigos… So, enjoy it !!!
See you all at the weekend edition of the program Saturday and Sunday UTC days… and don´t forget to send your signal reports , comments about the program and radio hobby related questions to arnie at rhc dot cu. Or VIA AIR MAIL to Arnie Coro, Radio Havana Cuba, Havana, Cuba