[BARC-List] DXers Unlimited

[Dan Malloy]

Hello to all,
   If you're not on HF, Arnie Coro, CO2KK, has an excelllent Ham radio and DX program on Radio Havana Cuba.  I gleaned the text from his latest show from the Ontario DX Assoc. reflector.
Dan

Radio Havana Cuba 
Dxers Unlimited 
Dxers Unlimited's mid week edition for 31 Jan - 1 Feb 2006 
By Arnie Coro 
Radio amateur CO2KK 

Hi amigos radioaficionados !! Sunspot count is ZERO !!! Yes, once again we
are watching at an absolutely SPOTLESS  SOLAR DISK. a very good indicator
that cycle 23 is coming to an end. But still no signs of the high latitude
sunspots that should signal the startup of cycle 24. Spotless SUN plus quiet
geomagnetic field translates into excellent low frequency propagation, and
that's exactly what we have heard during the past two days. 
Item two: CW Morse code is no longer in use by professional commercial
communications systems, but , radio amateurs continue to enjoy operating on
CW and making nice DX contacts with low power and simple equipment. 
For the past several days I have operated CO2KK, my ham radio station on 40
meters CW, around 7040 kiloHertz, a frequency favored by low power operators
and also at the very edge of the band, between 7001 and 7006 kiloHertz,
where many DX hounds gather . On and around 7040 kiloHertz, using slow speed
CW, between 8 and 15 words per minute, it is possible to enjoy many nice two
way contacts, while using power outputs between 1 and 5 Watts. At the band
edge, you will certainly need more power to get through the QRM caused by
high power operators !!! Learning CW Morse Code to an acceptable level is
not that difficult, especially if you are able to download G4FON's Koch
software trainer.This program is an excellent one, well written and that you
can tune according to your progress . Many radio amateurs that obtained
their licenses under the no Morse Code provisions now available in many
countries, have later discovered how interesting CW really is, and how one,
little by little, can improve both reception and transmission speeds. 
If you start operating on CW, use a transmitting speed where you feel
comfortable, and you will find that the station in contact with you will 
In most cases kindly match her or his transmitting speed accordingly, making
a nice QSO  possible. 
Using my very simple two vacuum tubes regenerative receiver and a one vacuum
tube transmitter, connected to a half wave dipole antenna, I have made
hundreds of two way contacts around the world, a good demonstration that
amateur radio need not be an expensive hobby at all. Both my receiver and
transmitter were built from recycled parts, atop breadboards, and when
operated on the 40 meters band with about 5  Watts output, CO2KK has reached
as far as Japan, Australia, New Zealand, India, the Middle East and Europe
on a regular basis when propagation conditions were reasonable. And even
under poor propagation two way CW QSO's are possible with stations located
in the Americas !!! 
Stay right on this frequency as the mid week edition of Dxers Unlimited
continues in just a few seconds after a short break. I am Arnie Coro in
Havana and my ham radio callsign is CO2KK. Charlie Oscar Two Kilo, Kilo. 
.. 
Si amigos, yes my friends, the solar cycle is going fast to an end, but
don't worry much, cycle 24 is about to start sometime during 2006 !!!  Now
here is our next item of today's mid week edition of Dxers Unlimited.While
solar activity dwindles, you will have lots of time to homebrew new radios
or repair old ones. Collecting antique radios is one of the most fascinating
aspects of this hobby, and even not too old radios offer a great thrill if
you are able to revive them. For example, a member of my Plaza Radio Club
recently obtained a 1963 vintage Chinese communications receiver. It is a
vacuum tube design covering from 1.5 to 25 megahertz, it's a single
conversion radio with a 465 kiloHertz intermediate frequency, and according
to my perception it is not a collectors item. So, my friend found the
workshop manual,and has not only put it back to work, but also made several
worthwhile modifications, like installing a 455 kiloHertz IF mechanical
filter, retuning the IF transformers to that frequency and he is now using
this model R403 radio for the frequency range between 1.5 and 10 megaHertz
with excellent results. Above 10 megahertz the single conversion radio has
IF image problems, so he is now gathering the parts to build a converter, so
that he can tune to the 20 meters band between 3 and 3.350 megaHertz using
an 11 megaHertz crystal that we found in my junk box. This more than 40
years old radio is in beautiful shape, because it uses oil filled filter
capacitors that have a much longer lifetime than electrolytics. By the way
if you ever come across an old radio, especially 
If it is a vacuum tube type receiver, never, and I mean it, never plug it
into the power line before testing the electrolytic capacitors of the power
supply,and conducting a one by one check of the bypass capacitors that are
connected from the plate and screen grid electrodes to ground. 
Restoring transistor receivers is another different story, and in an
upcoming edition of Dxers Unlimited I'll give some tips about solid state
equipment restoration, especially applicable to the first generation of
transistor radios that used discrete, individual components and no
integrated circuits.. 
.. 
This is the mid week edition of Dxers Unlimited, I am Arnie Coro in Havana
and amigos, I want to say thank you to all listeners that keep sending me
your opinions about the program. I am fully aware that it is quite a
challenge to attempt to cover all aspects of the radio hobby, but what a
great reward comes when  a Dxers Unlimited fan tells me an e-mail that she
or he has heard a new station, received a QSL card from a far away amateur
station, or communicates the thrill experienced by the whole family when a
homebrew radio comes to life after soldering the last connection and
checking all the wiring very carefully. Just this past week I received two
nice letters from listeners that have just completed new radios, one a very
sophisticated solid state design that I had sent him about a year ago, so
that he could have an idea of how a homebrew radio could match a factory
built one. and the other listener was extremely happy with his three
transistors simple radio that he had built with his son, and that by one of
those wonderful coincidences in life, was completed just a few minutes
before Dxers Unlimited went on the air last Saturday evening. Amigo Mark and
his son Andrew jumped from their seats, when the transistor regenerative was
connected for the first time, and they picked up Radio Havana Cuba on our 6
megaHertz frequency almost immediately after connecting the 9 volts battery.
By the way, that receiver is a version of my good friend Paul Harden's NA5N
Dessert Rat regenerative, that together with Charles Kitchin design form
part of receivers that can be homebrew with readily available parts. .. 
.. 
ASK ARNIE. ASK ARNIE,,,, send your radio hobby related questions to ASK
ARNIE here at Dxers Unlimited, and you will receive a fast answer, and also
help other Dxers Unlimited's listeners that may have similar questions .
Today's question came from Canada, listener Barry who lives near Saint John,
Nova Scotia wrote an e-mail asking me about surface mounted devices, the
very small components now used in most electronic equipment. Well amigo
Barry, SMD parts, are as you already realized very small and not so easy to
handle as electronic components that have pigtails to solder them. but one
can certainly learn how to work with Surface Mounted Devices , if you are
willing to spend some time practicing how to solder them in place. I won't
recommend using SMD components by beginners, but more experienced radio
hobby enthusiasts can certainly develop the skills if you use the proper
tools, magnifying glass and proper illumination. My favorite way of
assembling simple homebrew projects is the so called ISLANDS method, because
it is so easy to work with, doesn't require the use of etching chemicals for
making printed circuits, and you can optimize the designs following a step
by step process. For example amigo Barry, my three transistor regenerative
receiver that has become so popular among Dxers Unlimited's listeners when
built using the small isolated printed circuit pad islands glued to a piece
of printed circuit board works exactly as well as the printed circuit
version, and the same happens with my favorite AM Broadcast band up
converter that makes good use of my 
UNIDEN-Radio Schack HTX100 transceiver during the local evening hours, when
the 10 meters band is totally dead for DX.So, once again, don't get involved
with SURFACE MOUNTED DEVICES , or SMD components , in my opinion, using them
is only worth the effort when you are working with UHF and Microwave
circuits !!! 
... 

Antennas, Antennas, and more Antenna designs keep coming from all around the
world. Dxers Unlimited's listeners have sent during the past three weeks no
less than eleven differente antenna designs for me to evaluate. a process
that , as expected takes a lot of time.All I can say amigos that there are
many time proven, reliable, efficient and low cost antenna designs , that
despite their simplicity perform very well. Take for example the 5 band
vertical antenna that I have installed supported by the top guy wire of one
of my antenna towers.. The steel rope guy wire was replaced by a new one
with 6 ceramic insulators.. And vertical antennas for the 20,17,15,12,10 and
6 meter bands , all fed with  50 ohm coaxial cable hang from the guy wire .
There is a simple ground system that connects to the shield or braid of the
coaxial cable, and the six antennas were carefully tuned to minimum standing
wave ratio at the desired operating center operating frequency. The wire
antennas hang from the guy wire by means of dacron ropes. This is not an
antenna that can be compared with a 10 element log periodic, or a single
band 5 element Yagi array, but all I can say is that it works quite well as
a rugged standby antenna that defied the fury of three hurricanes without
breaking up !!! 
And now amigos, as always at the end of the program, when I am here in Havana, here is Arnie Coro's Dxers Unlimited's HF plus low band propagation update and forecast. Solar activity is extremely low, with the optical sunspot count very near zero, The effective sunspot number is 20 , and that's an indicator of very low maximum useable frequencies during the local daylight hours, and of a fast drop just after sunset. Best daytime propagation will peak up to the 16 meters international broadcast band and the 18 megaHertz or 17 meters amateur band, while during the local evening hours you will be able to enjoy excellent reception on frequencies from 100 kiloHertz all the way up to 8 megaHertz , but not much higher than 10 megaHertz. Hope to have you all listening to the weekend edition of Dxers Unlimited amigos, and don't forget to set aside a little time to send me your radio hobby related questions, ideas on how to improve this program and tips that other listeners may be able to use too. Send mail to arnie at rhc.cu or VIA AIR MAIL to Arnie Coro, Radio Havana Cuba, Havana Cuba.