RADIO HABANA CUBA
DXERS UNLIMITED
WEEKEND EDITION
SATURDAY, JULY 14, 2001
By Arnie Coro CO2KKSend your comments, questions and ideas to: arnie@radiohc.org
Hi amigos! Welcome to the weekend edition of Dxers Unlimited, your favorite listener oriented radio hobby program, both on the air and on our Dxers Unlimited website... I am Arnie Coro, radio amateur CO2KK, your friend here in Havana and host of this twice-weekly program -- entirely, absolutely, devoted to the promotion and development of our wonderful and fascinating hobby, the one you and I enjoy so much: RADIO!!!! Here is our menu for today...
ITEM ONE: another Dxers Unlimited's HF propagation forecast right on target... Scientists now agree that the peak of this solar rotation will not match the two previous ones, so expect a peak during the next few days to reach perhaps around 170 solar flux units or so, if no new sunspot active region shows up out of nowhere!!!
ITEM TWO: Ham radio contests during this weekend... TWO of them: The International Amateur Radio Union yearly RADIOSPORTS contest on the HF bands, and the CQ VHF contest for 6 and 2 meter band enthusiasts will provide radio amateurs with two different ways of having a nice time by participating in either one or even in both of them, as I plan to do here... NO, don't think I'll be one of the winners, as not enough time is going to be available here for contest operation of CO2KK, BUT you can be sure that even when one's participation in a contest is limited to an hour or two, you will have a nice time, and many of the top-notch competitors will be very thankful to your limited on the air time, as YOU provide THEM with more contest points and multipliers!!! If you are not a licensed radio amateur operator, then you can monitor the HF contest with a receiver capable of tuning to Single Side Band and CW signals!!!
ITEM THREE: A lot of sporadic E events during the past several days, and some of them are happening during the local evening hours making possible the participation of more amateurs... As a good friend of mine likes to say, sporadic E openings seem to happen 90 percent of the time when I am at work!!!
Stay tuned for more radio hobby related information coming to you from Havana... My sound engineer and producer is Margarita Delgado, I am Arnie Coro, back with you in just a few seconds..
You are listening to the weekend edition of Dxers Unlimited, amigos! And here are just a few of the goodies available to dedicated radio amateur DX hunters... listen carefully...
BANGLADESH, S2 is the prefix...
John, KX7YT, is signing S21YV from Dhaka operating in SSB/PSK31 on 15m and 20m from 1400-1800 UTC between Jul 15 and Aug 5.
BERMUDA, VP9
G0KOM IS QRV on HF and 6m from Jul 14-22. He will listen especially for Europe on 50 MHz.
CANADA, VE
VE2A is QRV from rare CQ zone 2 from Jul 21-24. Frequencies: CW: 3505, 7005, 14005, 21005, 28195 kHz, SSB: 3795, 7095, 14295, 21195,28495 kHz. Sure! rare CQ zone 2 is typically only activated during contests... a good chance to work VE2A for those of you that are zone hunters!
DANJO ARCHIPELAGO, JA, Islands on the Air, IOTA, program designator AS-056.
Masa, JA6GXK, will be QRV on 14260 or 21260 MHz +/-10kHz during his spare time from July 13-24. QSL via bureau only.
ELEUTHERA ISLAND, C6 is the prefix of Bahamian stations and the Islands of the Air program IOTA designator is NA-001
Mike,KJ4Z, Dan,K2VOL, and Bret,K4TKE, are QRV from Jul 13-22. They plan to work in SSB/CW/RTTY on 80-10m. QSL via KJ4Z.
FALCON STATE ISLANDS, YV
YW1F will be active from Cayo Sombrero, which was not activated before, during the Venezuelan Navy Day 2001 from Jul 20-24. Activity takes place on HF and 6m. QSL via YV bureau.
FAROE ISLANDS, OY, a rather rare prefix, part of Denmark
Volkmar, DF2SS, will be QRV in SSB/CW/RTTY on all bands incl 2/6m from Jul 20 till Aug 8. They intend to participate also in the IOTA Contest.
HARADSSKAR ISLAND, SM5, EU-177
The Grantham Amateur Radio Club will activate this island signing SM5/G0GRC/p from July 21-25. QSL via G0RCI direct or bureau.
HONSHU ISLAND, JA4
DD0VR is on the air as 7N4OKY running 10 wtts in SSB/CW on 3537.5,3798, 7050, 21225, 24940, 28850 and 52000 kHz from Jul 1-26.
ICELAND, TF
After visiting Faroer Fabian, DJ1YFK, is QRV in CW signing TF/DJ1YFK/p from different locations throughout Jul 12-19.
SAO SEBASTIAO ISLAND, PY, SA-028
The op's Anderson,PY2TNT, Adriano,PY2AXH, Alex,PY2RAZ, David,PY2DCE, Marco,PY2MTF, and Osvald,PY2MWS, are signing PX2I until Jul 31. QSL via PY2TNT, bureau ok.
SHIKOTAN ISLAND, UA0, AS-062 and MONERON ISLAND, UA0, AS-149
RA0FF, RA0FU and RA0FW plan to activate these two islands in July or August. They applied for the call RI0F.
SOMALIA, T5
Bruce,WD4NGB, got a license to operate as T5DX from July 1, 2001 until July 1, 2002. He is now planning a DXpedition for autumn. Please check!
And finally, from the Caribbean Islands of ST CHRISTOPHER AND NEVIS, V4
Larry,KJ4UY, will be on the air as V47UY opearting from the shack of V44NK on Nevis from Jul 20-31. He plans to work in CW/SSB/RTTY/PSK31 on 6-160m. QSL via KJ4UY.
And NOW a bit of Ham radio-related Geography for Dxers Unlimited's listeners' enjoyment...
Nevis Island:
Nevis is situated at 17°10'North and 62°34'West North of the Antilles. Columbus discovered this island in 1493 and saw the highest mountain Nevis Peak in clouds. Since he thought he saw a snow covered peak he named the island "Nuestro Senora de las Nieves."
Its neighboring island, St. Kitts, was the first island of the Antilles settled by the English in 1623; Nevis was settled in 1628. After belonging to France and England again and again, the Republic of St. Christopher and Nevis became independent in 1983. Since the name is very long it's mainly called St. Kitts and Nevis.
Amateur radio: Prefix V4, DXCC entity St.Christopher and Nevis, WAZ zone 8, ITU zone 11, UTC -4 hours. This DXCC is being visited by HAMs frequently.
And now here is our ever-popular "You have questions and Arnie tries to answer them" section of Dxers Unlimited. Mail your radio hobby and electronics related questions to arnie@radiohc.org
Today's question was sent by listener Bud Baechler; here is his e-mail to me:
Subject: Antenna Tuners
Date: Fri, 13 Jul 2001 09:26:37 -0500Mr. Coro...
Can you recommend specific commercially-available antenna tuners for primary use on the AM broadcast bank (500-1700 kHz) and on short-wave bands as well?
Perhaps I will need two units. I have looked at the MFJ devices (1046 &1048 tuners and the 1025 &1026 antenna phase units) but they advise me that performance might suffer on the broadcast band. I would appreciate your advice.
Bud Baechler
OK amigo Bud, here is the answer to your question... to the best of my knowledge, there is no such thing as a commercially built antenna tuner for primary use on the AM broadcast band which, as you know well, covers from 530 to 1710 kiloHertz... There are many nice HF antenna tuners available though, but those don't tune usually below the 160 meter or 1.8 megaHertz amateur band. I already answered your question direct back to you via e-mail, but, I thought that many other Dxers Unlimited's listeners would like to know a bit more about AM broadcast band antenna tuners....
I must say that my own KK DASH AM antenna tuner is not a beginner's project, as it does include a sophisticated step attenuator, an embedded vacuum tube pre-amplifier stage that can be switched on or off as needed, and it also includes a complex filter at the input to block any signals from 2 megaHertz UP.... This filter is very useful if you are located near VHF high power transmitters that can generate intermodulation products...
So, to summarize, NO, there is no commercially available AM broadcast band antenna tuner, and YES, you must build your own, something that you can do by following one of my two circuit diagrams, the KK DASH AM SIMPLE, without the low pass filter at the input or the preamplifier or the more complex KK DASH AM. You will need to find high quality variable capacitors, and the coils must be wound using LITZ wire for maximum efficiency, but, of course... you can use standard enamel wire to wind the coils and still end up with a pretty nice AM band tuner...
And just for FUN, listen to what I do to demonstrate how well the KK DASH AM works... When someone is visiting my shack, I connect a germanium diode, a bypass capacitor and a pair of high impedance headphones to the KK DASH AM, and make the person listen to the AM broadcast band stations with just a few meters of wire connected to the antenna input terminal... Several of my local AM broadcast stations come in nicely with that simple setup!!!
AH! and before I forget, the KK DASH AM, the really sophisticated version does require four good-quality 300 to 400 picofarads maximum capacity variable capacitors... Two for the tuner itself, and two for the radio frequency amplifier stage... ALSO, you may want to know why I use a vacuum tube, a radio frequency amplifier pentode, instead of a much more modern MOS FET high gain transistor... Well, the answer is pretty simple, amigo!!! I simply got tired of changing burned-out FET's, as my long wire antenna used for AM medium wave band DXing seems to generate huge peak voltages from rather far away thunderstorms...so I ended up with the vacuum tube amplifier, a neon bulb input protector and since then, no more problems!!!
And now, amigos, as always at the end of the show, here is one of your favorite sections of Dxers Unlimited... Arnie Coro's exclusive and not copyrighted propagation update and forecast:
Solar flux is moving slowly up, and if no new solar active regions appear from nowhere, expect a peak of solar activity for this rotation between 160 and 180 units. BUT, do remember that the SUN is unpredictable, and that suddenly a new sunspot region can appear and change everything. Scientists are now using a new sophisticated method to detect sunspot regions that exist on the side of the Sun that we don't see, and so far their analysis for the last few days show very little signs of activity, something that accounts for the expected lower solar flux peak.
I spent some time Saturday morning trying to work stations in the IARU Radiosports Championship Contest, and soon found out that conditions on 10 were non-existent, while 15 meters provided a handful of North American stations, and I could hear just two or three Europeans, but could not work them trough the QRM due to an ongoing geomagnetic field disturbance. For short wave listeners the best period of the day for easy listening is from just after local SUNSET to just after local SUNRISE in the frequency range from 10 to 22 megaHertz.
Don't forget to send your QSL card requests, signal reports and comments about this show directly to me at arnie@radiohc.org and via AIR MAIL, a postcard will be fine... mail to Arnie Coro, Radio Havana Cuba, Havana, Cuba. See you next Tuesday and Wednesday UTC days at the mid-week edition of Dxers Unlimited!
Prepared 14-July-2001; transmitted 18-July-2001
Arnie Coro CO2KK
Havana, Cuba
July 14, 2001Postal address:
Arnie Coro, "Dxers Unlimited"
Radio Havana Cuba, Havana, CUBA
e-mail: arnie@radiohc.org
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