By Arnie Coro, CO2KK
Hi amigos radioaficionados and shortwave listeners around the world. This is the midweek edition of Dxers Unlimited coming to you from Havana. I am Arnie Coro, radio amateur CO2KK, the host of this twice weekly program devoted to the promotion and development of our wonderful hobby ... radio, the one and only you and I can enjoy in more than 81 different ways... from homebrewing simple radios like a two transistor plus one diode AM broadcast band receiver to designing and building an Earth-Moon -Earth antenna array with no less than 16 long 17 elements Yagis...
Hi amigos radioaficionados and shortwave listeners around the world. This is the midweek edition of Dxers Unlimited coming to you from Havana. I am Arnie Coro, radio amateur CO2KK, the host of this twice weekly program devoted to the promotion and development of our wonderful hobby ... radio, the one and only you and I can enjoy in more than 81 different ways... from homebrewing simple radios like a two transistor plus one diode AM broadcast band receiver to designing and building an Earth-Moon -Earth antenna array with no less than 16 long 17 elements Yagis...
Si amigos, this is a most enjoyable hobby and now that the winter DX season is in full swing here in our northern hemisphere we are seeing some very interesting propagation conditions that provide lots of DX even for radio amateurs running low power and simple antennas...And this is happening despite the very low solar activity that has prevailed from many weeks now. Here is item one. Solar flux at rock bottom lvels while the A index, the planetary geomagnetic disturbance indicator is at a rather nice and low level...
Item two: results obtained with the MICRO VERT simple antenna have surprised many of those who have built it ... another simple antenna that also brings nice results despite its simplicity of construction is the BOBTAIL curtain, an antenna especially useful for long haul DX as it has a very low take off angle even at low heights above ground. You will need quite some space to install a three element BOBTAIL, but its smaller counterpart , the HALF SQUARE will also provide rather outstanding results. A HALF SQUARE built for the 10 or 15 meters amateur bands using just wire and dacron fishing lines for insulators is extremely easy to homebrew ... a similar antenna for the two meter band is my favorite choice for accesing repeaters located in opposite direction.
Item three: Comments from listener Miguel regarding variable reception with deep fading and sometimes the signal just vannishing is quite characteristic of short paths on frequencies above 6 megaHertz... That's the reason why he can copy all day long the Radio Rebelde station on 5025 kiloHertz, on the 60 meters Tropical Band , while our 6 and 9 megaHertz frequencies are sometimes difficult to copy at his QTH in Florida when HF conditions are not too good. Item four of today's Dxers Unlimited will be dealing with the HALF SQUARE antenna.
This is the midweek edition of Dxers Unlimited amigos, and here is our ANTENNA TOPICS section of the program...today providing you with information about the HALF SQUARE single band wire antenna. If you have space for just one horizontal half wave dipole antena , my advice is not to install such antenna , and instead try to use up the horizontal space to install a vertically polarized DX antenna, the HALF SQUARE. My 20 meter band HALF SQUARE fed directly with RG213 coaxial cable has proven to be anywhere between one and three S units above the half wave wire dipole that it replaced. The reason why the HALF SQUARE has proven to be so effective for working DX, is the fact that even at low height above the sorrounding terrain, the HALF SQUARE sends out a low take off angle signal... in other words the HALF SQUARE will be much more useful for Dxing than a half wave wire dipole, or even a two element Yagi installed at a similar low height.
Another important advantage of the HALF SQUARE is that it is vertically polarized, something that produces much less interference than what is generated by the use of any type of horizontally polarized antenna. The "wrong polarization"has an outstanding effect in reducing TVI or television interference... The TV signal reaching a TV set is horizontally polarized, and that's why many newcomers to amateur radio are using the HALF SQUARE, a vertically polarized antenna that will attenuate the horizontaly polarized signal by as much asn 100 times, and that in turn will solve many TVI problems.
There is something that you must know about both the HALF SQUARE and the BOBTAIL vertical curtains, and that is the fact thay they are by design, single band antennas.As my good friend Bob Chandler from the Ontario DX Association is one of the most enthusiastic users of HALF SQUARE antennas for his CQ Zone 2 Contest Stations way up north in Canada, I want to quote him here today...Bob told me after a very succesful contest station operation using the HALF SQUARES that they provided extremely good performance and could be transported very easily. The Canadian contest team used PVC pipe masts that are both lightweight and transparent to radio frequency energy, so that they don't distort the antenna's radiation pattern.
Here in Havana, I am using a 2 meter band version of the HALF SQUARE to solve a problem. We have two long range mountaintop repeaters, one to the West and the other one to the East of the Havana metropolitan area...With the HALF SQUARE I can reach both of them with about 4 dB gain , providing excellent communication while running only one Watt on my 2 meter band handie talkie...
Item two: results obtained with the MICRO VERT simple antenna have surprised many of those who have built it ... another simple antenna that also brings nice results despite its simplicity of construction is the BOBTAIL curtain, an antenna especially useful for long haul DX as it has a very low take off angle even at low heights above ground. You will need quite some space to install a three element BOBTAIL, but its smaller counterpart , the HALF SQUARE will also provide rather outstanding results. A HALF SQUARE built for the 10 or 15 meters amateur bands using just wire and dacron fishing lines for insulators is extremely easy to homebrew ... a similar antenna for the two meter band is my favorite choice for accesing repeaters located in opposite direction.
Item three: Comments from listener Miguel regarding variable reception with deep fading and sometimes the signal just vannishing is quite characteristic of short paths on frequencies above 6 megaHertz... That's the reason why he can copy all day long the Radio Rebelde station on 5025 kiloHertz, on the 60 meters Tropical Band , while our 6 and 9 megaHertz frequencies are sometimes difficult to copy at his QTH in Florida when HF conditions are not too good. Item four of today's Dxers Unlimited will be dealing with the HALF SQUARE antenna.
This is the midweek edition of Dxers Unlimited amigos, and here is our ANTENNA TOPICS section of the program...today providing you with information about the HALF SQUARE single band wire antenna. If you have space for just one horizontal half wave dipole antena , my advice is not to install such antenna , and instead try to use up the horizontal space to install a vertically polarized DX antenna, the HALF SQUARE. My 20 meter band HALF SQUARE fed directly with RG213 coaxial cable has proven to be anywhere between one and three S units above the half wave wire dipole that it replaced. The reason why the HALF SQUARE has proven to be so effective for working DX, is the fact that even at low height above the sorrounding terrain, the HALF SQUARE sends out a low take off angle signal... in other words the HALF SQUARE will be much more useful for Dxing than a half wave wire dipole, or even a two element Yagi installed at a similar low height.
Another important advantage of the HALF SQUARE is that it is vertically polarized, something that produces much less interference than what is generated by the use of any type of horizontally polarized antenna. The "wrong polarization"has an outstanding effect in reducing TVI or television interference... The TV signal reaching a TV set is horizontally polarized, and that's why many newcomers to amateur radio are using the HALF SQUARE, a vertically polarized antenna that will attenuate the horizontaly polarized signal by as much asn 100 times, and that in turn will solve many TVI problems.
There is something that you must know about both the HALF SQUARE and the BOBTAIL vertical curtains, and that is the fact thay they are by design, single band antennas.As my good friend Bob Chandler from the Ontario DX Association is one of the most enthusiastic users of HALF SQUARE antennas for his CQ Zone 2 Contest Stations way up north in Canada, I want to quote him here today...Bob told me after a very succesful contest station operation using the HALF SQUARES that they provided extremely good performance and could be transported very easily. The Canadian contest team used PVC pipe masts that are both lightweight and transparent to radio frequency energy, so that they don't distort the antenna's radiation pattern.
Here in Havana, I am using a 2 meter band version of the HALF SQUARE to solve a problem. We have two long range mountaintop repeaters, one to the West and the other one to the East of the Havana metropolitan area...With the HALF SQUARE I can reach both of them with about 4 dB gain , providing excellent communication while running only one Watt on my 2 meter band handie talkie...
If you need more information about both the BOBTAIL three element and the HALF SQUARE two element vertical arrays , go to http://www.cebik.com the wonderful website created by Dr. L.B. Cebik Ph D, amateur radio operator W4RNL, who has made available to the world's
amateur radio enthusiasts an incredible collection of antenna information...
again the URL is http://www.cebik.com/
.....
Si amigos, we are working hard here to improve the quality and reliability of Cuba's broadcasting service on short wave, AM , FM and Television. RadioCuba, the totally state owned company that is in charge of the transmitters is now well advanced into the installation of new AM, FM and TV transmitters all along the Cuban archipelago.
At the Isle of Youth, Radio Caribe is now with a new 5 kiloWatt AM transmitter operating on 1220 kiloHertz and RadioCuba engineers also installed an FM transmitter there operating on 101.7 megHertz with 3 kiloWatts effective radiated power, more than enough to cover the Isle of Youth and the adjacent Cayo Largo tourist resort.
amateur radio enthusiasts an incredible collection of antenna information...
again the URL is http://www.cebik.com/
.....
Si amigos, we are working hard here to improve the quality and reliability of Cuba's broadcasting service on short wave, AM , FM and Television. RadioCuba, the totally state owned company that is in charge of the transmitters is now well advanced into the installation of new AM, FM and TV transmitters all along the Cuban archipelago.
At the Isle of Youth, Radio Caribe is now with a new 5 kiloWatt AM transmitter operating on 1220 kiloHertz and RadioCuba engineers also installed an FM transmitter there operating on 101.7 megHertz with 3 kiloWatts effective radiated power, more than enough to cover the Isle of Youth and the adjacent Cayo Largo tourist resort.
At the same time, the Cuban Broadcast Institute implemented a modernization plan at the Radio Caribe studios using digital technology. The Radio Caribe studios are linked to the FM transmitter using a digital UHF link, and soon the analog UHF link to the AM site will be replaced by a new digital one too. Similar projects are in progress all along the Cuban archipelago, like for example in Matanzas province, east of Havana, where the old Radio Rebelde 30 kiloWatt Tesla transmitter that I helped to install in 1963 was replaced by a new solid state 25 kiloWatt transmitter capable of up to 125 percent positive peak modulation. Radio Rebelde's Matanzas relay is operating on 620 kiloHertz , while at the same site, a new Radio Reloj network also solid state transmitter is running 5 kiloWatts on 860 kiloHertz, improving the coverage of that news and information broadcast service.
Cuba's fourth national TV network transmitters are now on the air too.
Item Five: The popular you have questions and Arnie tries to answer them...
You can send your questions to arnie@rhc.cu, and the answer will go right back to your mailbox pretty fast... Here is today's question: It was sent by listener Kate in Vancouver... She says that now she is having some difficulty copying the 6000 kiloHertz English language broadcast from Radio Havana Cuba... Well amiga Kate, I ran several computer software programs used here to calculate the frequencies that should be used for a given part of the world, solar activity etc. and sure, you are right, each time a geomagnetic disturbance caused by the now so frequent coronal holes is in progress, reception of our 6000 kiloHertz in Vancouver should be rather difficult, especially when the antenna is not beaming in your direction. Let me remind you and other Radio Havana Cuba listeners located along the Pacific Coast of North America, that we beam into that area from 05 to 07 UTC ...
If you are able to listen to us from 01 to 05 hours UTC , then you are actually picking up the beam that is centered on Eastern Region of North America, so the signal intensity at that time in Vancouver should not be very strong... Maybe soon we will be able to broadcast on one more frequency , so that at the same time we may be beaming to Eastern North America, the Great Lakes Region on two frequencies and the Pacific Coast using another frequency.
Today's second question, came from South Africa, where several listeners are reporting our 11760 kiloHertz English language broadcast... Amigo Alex from Cape Town wants to know if I have heard about a new version of the BAYLISS crank up generator that is capable of providing power to a radio for periods lasting up to two hours.
Well amigo Alex, I have seen and actually tested several models of AM, FM and SHORT WAVE radios that use the crank-up Bayliss generator for powering up the receiver by cranking up for about 30 seconds to make the radio play for about half and hour. By the way , for those of you that have not heard about the BAYLISS crank-up generator, let me explain that it was invented by a South African and is now becoming extremely popular not only for powering radios, but also for many other applications where expensive batteries may be replaced by this unique system. The BAYLISS Direct Current crank up generator is a very reliable source of electricity for powering up radios during emergencies !!!
Cuba's fourth national TV network transmitters are now on the air too.
Item Five: The popular you have questions and Arnie tries to answer them...
You can send your questions to arnie@rhc.cu, and the answer will go right back to your mailbox pretty fast... Here is today's question: It was sent by listener Kate in Vancouver... She says that now she is having some difficulty copying the 6000 kiloHertz English language broadcast from Radio Havana Cuba... Well amiga Kate, I ran several computer software programs used here to calculate the frequencies that should be used for a given part of the world, solar activity etc. and sure, you are right, each time a geomagnetic disturbance caused by the now so frequent coronal holes is in progress, reception of our 6000 kiloHertz in Vancouver should be rather difficult, especially when the antenna is not beaming in your direction. Let me remind you and other Radio Havana Cuba listeners located along the Pacific Coast of North America, that we beam into that area from 05 to 07 UTC ...
If you are able to listen to us from 01 to 05 hours UTC , then you are actually picking up the beam that is centered on Eastern Region of North America, so the signal intensity at that time in Vancouver should not be very strong... Maybe soon we will be able to broadcast on one more frequency , so that at the same time we may be beaming to Eastern North America, the Great Lakes Region on two frequencies and the Pacific Coast using another frequency.
Today's second question, came from South Africa, where several listeners are reporting our 11760 kiloHertz English language broadcast... Amigo Alex from Cape Town wants to know if I have heard about a new version of the BAYLISS crank up generator that is capable of providing power to a radio for periods lasting up to two hours.
Well amigo Alex, I have seen and actually tested several models of AM, FM and SHORT WAVE radios that use the crank-up Bayliss generator for powering up the receiver by cranking up for about 30 seconds to make the radio play for about half and hour. By the way , for those of you that have not heard about the BAYLISS crank-up generator, let me explain that it was invented by a South African and is now becoming extremely popular not only for powering radios, but also for many other applications where expensive batteries may be replaced by this unique system. The BAYLISS Direct Current crank up generator is a very reliable source of electricity for powering up radios during emergencies !!!
And now amigos, as always at the end of the program , here is Arnie Coro's Dxers Unlimited's HF propagation update and forecast .Solar flux is now hovering around 72 units, and it is expected to continue at very low levels, optical sunspot count near ZERO and now the effects from a coronal hole that was located at a geoeffective position have ended, and this in other words means that propagation conditions will be a little better for the next two to three days,especially a latitudes above 40 degrees North. Very slight chances of sporadic E openings at this moment, while chances for tropospheric ducting are increasing especially all along th Gulf of Mexico region. I hope to see you all at the weekend edition of the program amigos , and don't forget to send me an e-mail with your comments about the program, as they do help make a better Dxers Unlimited for you all !!!
(Source: Arnie Coro, R Havana)
(Source: Arnie Coro, R Havana)