Dxers Unlimited’s week end edition for Sunday April 15 2012 by Arnie Coro, Radio Amateur CO2KK

Saludos amigos radioaficionados … Hi my radio hobby enthusiast friends around the world !Welcome to this weekend edition of Dxers Unlimited, your favorite listener oriented and technically minded radio hobby program. I am Arnie Coro, my ham radio callsign is CO2KK, and as always , twice weekly here I am ready to bring you about ten to eleven minutes of all radio hobby related information.

Now ready for item one: listener’s feedback via e-mail keeps me working the whole week amigos ! That is really nice, as it makes for a more appealing Dxers Unlimited ...

Here is now item two:radio noise is at this moment and will continue to be in the immediate future our number one problem… The implementation of the so called BPL technology, that is broadband over the power lines, was without any doubts the biggest threat ever to the radio hobby amigos ! But , fortunately, many tests done already have fully demonstrateding that BPL is not a very reliable technology at all, using the frequency range from 2 to 80 megaHertz.…

So, we may see BPL Broadband over the Power Lines just going down the drain, as users realize that it brings them and all their neighbors a lot of p problems, including severe interferences to vitally important radio communications emergency frequencies !!!

Si amigos, tips and techniques is becoming increasingly popular among you all so I will try to include this section more often … The Tip for today will be dealing with broken down amateur transceivers, and some notes on how to try to fix them. And as always , at the end of the show, I will be presenting Dxers Unlimited’s HF propagation update and forecast .

Stay tuned for more radio hobby related information coming to from Havana. I’ll be back with you in few seconds!!!

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Si amigos ! We do QSL, SURE, and our beautiful QSL cards may form part of your collection very easily, send me a signal report and comments about the program you hear to inforhc at enet dot cu and via Air Mail to Arnie Coro, Radio Havana Cuba,Havana Cuba !!! More about BPL and why it has proven to be a fiasco , a total failure ...BPL, broadband Internet access using the power lines for transmission of the digital information requires sending a certain number or radio frequency carriers over the AC power lines, so that the encoded digitalized data can be picked up by connecting a special box to the power line using circuits that will separate the digital information from the actual 60 Hz power line voltage.

The BIG problem is that no one has found, and I doubt very much it someone can do it, a way to keep the carrier frequencies retained within the wires that carry the AC power to each individual home.

In other words, frequencies between a bit less than 2 megaHertz and 80 megaHertz will be radiated into the vicinity, and I also expect carrier harmonics to appear, extending the frequency range of the interference well past the 160 megaHertz limit.

As you can imagine, digital signals covering up all the radio frequency spectrum from 2 megaHertz all the way up to 160 or even 200 megaHertz, will simply make impossible to use other radio services, including international short wave broadcasting,aircraft long range communications , safety systems that operate on the VHF low and VHF hi bands etc.

So far several national telecommunications authorities have banned the use of BPL with the present HF to VHF low band technology , and they are very seriously considering the possible experimental use of a totally different BPL system that uses higher frequencies !!!.

My advice continues to be to keep alert about BPL, and if the area where you live is wired up for this system, keep a close watch about the noise levels generated by the BPL system, and file a complaint with your local authorities as early as possible.

This may or may not prove to be effective, but my opinion is that as more experts become aware of the many radio systems that may be disrupted by the BPL installations, we may see shut downs and possibly the abandoning of that technology in its present form. Stay tuned for more radio hobby related information … I am Arnie Coro in Havana, back in a few seconds...

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This is Radio Havana Cuba, the name of the show is Dxers Unlimited, and our weekend edition continues with TIPS and TECHNIQUES that today will be providing information about both hybrid and fully solid state amateur radio transceivers that need to be repaired. You may find those broken radios at hamfests, garage sales, or maybe sitting on top of shelf at a radio amateur’s shack… they are now growing more and more in numbers because fewer people can be found to repair them than ever before.

Another limiting factor for the proliferation of broken down ham radio transceivers that are not repaired, is that even if you find someone that has the know how and the instrumentation required your repair bill will show a high cost, so high in fact that it may make it a better choice to buy a new one if you can afford it.

Nevertheless, here are a few tips about these older transceivers that in many cases may put them back to work. First of all, start taking a detailed visual inspection tour of the rig, using a high intensity light source and a magnifying glass… It’s surprising to see how many of these broken down rigs will give you immediate clues about what was the reason that they stopped working. Just to put you an example, recently I had the opportunity to take a look at a Kenwood TS520 rig, an excellent hybrid transceiver and one of the most well designed and rugged transceivers ever produced. The rig’s receiver was working quite well, but it won’t transmit. Following the detailed and well illuminated visual inspection procedure, I soon found out a badly burned final amplifier stage radio frequency choke, and two leaking electrolytic high voltage capacitors. The owner of the TS520 had operated the radio into a badly mismatched antenna system, and that burned the radio frequency choke… By the way, the TS 520 that had been out of service for several years, is now back on the air at the home of a disabled radio amateur !

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 And now here is la numero UNO, number one most popular section of the show, ASK ARNIE. Today I will be answering a question sent by listener Elias in Nicaragua . Amigo Elias sent a question to ASK ARNIE, he wants to know what can be done to reduce the size of a horizontal or vertical antenna to a minimum, and how much can an antenna be reduced in size and still work more or less properly. Well amigo Elias, just to give you an example, an antenna for the 40 meter amateur band, in this case a horizontal dipole, can be cut in size by about 60 percent,that is more than half,and still provide quite effective performance. The problem is how you do it, so as to keep losses at a minimum. A combination of both inductive and capacitive loading is the way to go, and I am sending to you via e-mail one of my most recent antenna designs, a 40 meter dipole that is just 9 meters or just a bit less than 30 feet…

Now a short form propagation update, after a period of very low solar activity two active sunspots regions are in sight and growing in size... The Friday April 13th geomagnetic storm was short lived, and no more storms are expected during the next several days...50 the sunspot number that day with around 95 solar flux ... Best bands for daytime short wave listening are 19 and 16 meters, with short periods when 13 meters will also be in good shape

Send your signal reports and comments to inforhc at enet dot cu and VIA AIR MAIL to Arnie Coro , Radio Havana Cuba, Havana, Cuba

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