The Next Big Geomagnetic Storm Poses An Astronomical Risk To Modern Man

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An Overview Of The Chinese Satellite Now Orbiting The Moon With Amateur Radio Capabilities

Chinese Amateur Radio Satellite

In Spanish with English sub-titles…quite interesting.


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Dxers Unlimited weekend edition for Sunday 16 September 2018

By Arnie Coro
radio amateur CO2KK

Hi amigos radioaficionados now enjoying slightly  better short wave propagation conditions as we approach the autumn equinox…. I am Arnaldo, Arnie, Coro your host here at the weekend edition of Dxers Unlimited your favorite radio hobby program coming to you from sunny La Habana Cuba, and here is now our first news item…. for a change, another broadcast station is going back to use short wave transmissions, to provide better service to its listeners…

Radio Nepal is now back on short-wave

Victor Goonetilleke just wrote on the Union of Asian DXers Facebook page on  13 September 2018:

Radio Nepal is back on short-wave after six years off the air on the 60 meters Tropical Band  by adding 5005 kHz to augment its national transmission grid broadcasting on MW and FM. According to a station official, Radio Nepal resumed short wave broadcasts from 02.00 – 5.00 p m Nepali time using a 10 kw transmitter at Khumaltar, Lalitpur in Kathmandu .

The same source said the station is using very low power. By all accounts, 5005 kHz is a difficult Dx catch for listeners outside of Nepal. Nepal is 5 hours and 45 minutes ahead of UTC.

Even though the station is running its old 10kW transmitter at present it can`t be more than a 1 kw or so. But the greater news is that Nepal is now available on Short Wave for Dxers

More radio hobby information follows… Radio amateurs in the states of North and South Carolina continue to provide much needed emergency communications after hurricane Florence impacted the east coast of the USA, as a category one storm, but this one was a large diameter event, that affected a large area with very heavy rains and storm surges… The American Radio Relay League sent several portable multi band stations to the area ahead of the arrival of the hurricane, while local radio clubs implemented the emergency plans to provide much needed alternate communications after damages to the cell phone and wired systems required the use of amateur radio stations.

Fixing broken down present days high technology radio equipment is extremely difficult, even when full information is available and the required test instruments can be used. Attemps to repair receivers, transmitters and transceivers using sophisticated solid state high density components is next to impossible nowadays, except when very simple problems are causing the failures… One good example is the typical battery contacts corrosion problems that often are the cause of intermittent operation… But once again, attempting to change springs that contact the negative side of batteries and small metal plates used for the positive terminals can prove to be very difficult if you don’t have the proper tools and the vitally important instructions on how to dissassemble the equipment so that you can access the affected areas….

So one vitally important reminder is to never leave batteries inside radios and accesories in storage, and check frequently the batteries for any signs of leaks that can cause permanent corrosion damages to equipment…. Make a check list of all your equipment that uses batteries and once a month open the batteries compartment and be sure that everything is OK… If you have any doubts about possible leaks, discard the batteries immediately and do it in the most ecologically friendly way as possible

QSL on the air: QSL on the air to the many Radio Havana Cuba listeners that are reporting our 15140 kiloHertz frequency that is now starting at eleven AM Cuba time, that is fifteen hours UTC with the full two hours of the Cuba Online magazine show that ends at 18 hours UTC, Then 15140 kiloHertz stays on the air with the same central North America 340 degrees azimuth beam with several languages feeds… The English slot is on from three to four PM local time, that is from 19 to 20 hours UTC… Send your reports of the 15140 kiloHertz 19 meters band frequency to inforhc at enet dot cu, and do include your postal mailing address so that we can send you a nice Radio Havana Cuba QSL Card…

Now more radio hobby related information….. the best time of the year for AM medium wave Dxing is just around the corner… Starting around the third week of September and lasting until the end of November the autumn and very early winter AM band Dx season this year should be at least as good as last year’s one that started when the number of sunspots went below 20… Listeners who asked why the autumn DX season for the AM broadcast band is typically better than the spring season, the answer is that during the months of March and early April atmospheric noise levels are higher than during September, and October….

By the way I am using a recently repaired very old Grundig Yacht Boy 220 Long Wave , Medium Wave, Short wave and FM radio for late evening AM band Dxing with very good results. Using the built in ferrite rod antenna on the AM Broadcast band during the daytime I am able to pick up ground wave signals from stations located up to 250 miles away , thanks to the low local noise level prevailing in the neighborhood where I live. A recent trip for a short vacation at the end of August to beautiful Varadero beach at a seaside location brought daytime signals from more than 350 miles away coming from Cuban stations located to the East of our main island and operating on the 1200 to 1620 frequency range…. Yes amigos, even an old analog receiver can prove to be an excellent tool for AM medium wave band Dxing, among other highlights because the old radios do not use noisy frequency synthetizers.

This is Radio Havana Cuba, the name of the show is Dxers Unlimited, I am your host Arnie Coro radio amateur CO2KK and now here is ASK ARNIE, the most popular section of this program… just slightly ahead of the HF plus low band VHF propagation updates and forecasts featured whenever possible at the end of the show…

Today I will be answering a question by listener Alberto who listens from Buenos Aires Argentina to our Internet streaming audio. He wants to know why it is not possible for him to pick up our English language programs using his nice short wave radio and external antenna. Well amigo Alberto the reason why it is quite difficult to pick our English transmissions via Short Wave at your location is that we use directional antennas to beam the programs to North America, Central America, the Caribbean and also to the Mediterrenean area of Europe. The highly directional antenna systems have what is known as a high front to back ratio, so, for example when we use the 6165 kiloHertz beam to Central North America, an azimuth of 340 degrees, the reverse of the beam is on 160 degrees, but the passive reflector used on that curtain array cancels the backward lobe so that very little signal is sent in that azimuth…..

By the way we do broadcast in Spanish and Portuguese to South America using identical antenna arrays that beam the signals to azimuths of 130 , 160 and 172 degrees from Havana to provide full coverage of all of South America …

No need to use high power to enjoy amateur radio, even with simple equipment that do not need the assistance of sophisticate computer sofware digital communications programs like JT 65 and the most recent widely used FT8…The unique joy of achieving a succesfull two way amateur radio contact with a DX station while running very low power, and simple radios is second to none amigos, and by the way here is a partial list of the most popular CW operating frequencies for QRP or very low power amateur stations are 7030 and 7040 on the 40 meters band, 10 dot 106 on the 30 meters band 14060 on 20 meters, 21060 0n 15 meters and 28060 on the 10 meters band….

Calling CQ using CW on those frequencies will in many instances bring back stations that regularly monitor them for QRP signals.

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Dxers Unlimited’s mid week edition for Tuesday 11 September 2018

Hola amigos…. more reasons for the very poor propagation conditions on the MF and HF bands. Geomagnetic conditions have reached moderate storm levels on a planetary level (NOAA Kp 6 for the 6-9UT period today, 11 September 2018). The storm is due to the enhanced solar wind parameters associated with a coronal hole high speed stream, while the solar wind speed gradually increased from 370 km/s at noon 10 September to values near 610 km/s at 10UT today.

Now more radio hobby related information useful for planning your on the air activities….

DXCC COUNTRY/ENTITY REPORT: According to the AR-Cluster Network for the week of Sunday, 2nd/September, through Sunday, 9th/September  they were 206 DX countries or entities on the air on the monitored amateur bands.

I am Arnaldo, Arnie, Coro your host here at the middle of the week edition of Dxers Unlimited. Now our next news item… A number of hand held FM transceivers capable of transmitting on frequencies beyond the 2 meters and 70 centimeters band are being banned by several frequency management authorities around the world. The usually very low cost dual band FM handie talkies are considered a menace because they can easily be reprogrammed to operate on the public services frequencies. Banning those radios is achieved by placing them in black lists kept by Customs in the countries were they are no longer allowed to be imported.

QSL on the air… QSL on the air to Dxers Unlimited’s listeners that have asked to keep the HF bands propagation updates at the end of the show on every program…. Don’t worry, from now on whenever possible  Arnie Coro’s HF plus low band VHF propagation update will be on the air at the end of the show.

Next news item : Sponsored by the International Telecommunications Union, ITU, the specialized oldest United Nations agency, a worldwide research project that is measuring the radio frequency spectrum noise levels will provide valuable information about this severe problem that has a negative impact on the use of radio telecommunications systems that are vital in today’s world….

By the way some of the worst radio broadband noise levels measured at several megalopolis, like Mexico City, New York, London, Shanghai, Tokio, Moscow and Paris are showing that the AM broadcast band services are becomming useless at the present transmitting stations power levels… The actual effective service area originally planned for many AM broadcast stations since 1959 have proven to be practically useless due to the poor signal to noise ratios prevaling on the 530 to 1700 kiloHertz frequency range….

Hurricane Florence now in an almost fixed track is going to impact the US East Coast as a category 4 or even category 5 storm, the most powerful to reach that part of the continental USA in more than 60 years… Amateur radio operators located in the affected areas as well as others around the first skip HF coverage area are already deploying their emergency communications stations.  It is expected that the record breaking winds will produce considerable damage to the telecommunications and broadcasting facilities. As it happened last year in Texas, the cellphones networks went down even before the full blast of hurricane Harvey had hit the area, making the use of amateur radio emergency systems essential for responding to life saving operations requiring air evacuations from flooded isolated areas…

Number 94 is here… Yes amigos, the number 94 way of enjoying our spare time by means of our radio and  TV hobby is here: It is known as amateur digital television, capable of high definition transmissions. For   delivery   of   TV   signals,   there   are   several methods   in   use,   including:     cable   (C), satellite (S), terrestrial (T), internet streaming (www), DVD, etc.    Each delivery system has   it’s   own   advantages   and   disadvantages.      As   a result,   different   digital   encoding mechanisms are used for each method.     The cable, satellite and terrestrial all use RF carriers, while satellite and terrestrial are truly over the air rf paths.   As radio amateurs, we use over the air rf transmission paths.

In the early days of DTV (early 2000s), some DTV hams were experimenting with using satellite TV equipment, mainly due to the low cost (? $25) of free-to-air (FTA) satellite, L-band (1-2GHz) receivers.   Their work was primarily   on   the 23cm   (1.2GHz)   band.   Other   early   adopter  DTV  hams experimented using cable TV equipment for the same low cost reasons. The   normal   amateur   radio   environment   is   really   the over   the   air,  Terrestrial,   rf transmission   with   radio waves   being   transmitted   horizontally   over   the surface   of   the earth.   The major issues encountered with such radio waves is the presence of multi-path, RFI and weak signals. Multi-path refers to multiple rf signals bouncing off of various reflectors, such as hills, buildings, etc. and arriving at the receiving antenna with various time delays.   In the days of analog TV, this was readily evidenced by the presence of “ghost” signals on the TV screen. DTV  transmission   in   a   cable  TV  environment   is   rf transmission   in   an   almost   perfect environment.   It is almost a perfect, echo free environment due to the efforts made to maintain very low VSWR in the cable TV system.   Signal strengths can also be kept up to relatively high levels.   Thus the digital modulation method for cable TV does not need to make many corrections for it’s good environment.

DTV   transmission   from   broadcast   TV   satellites   is again   in   a   relatively   clean   rf environment.   Because of the high gain and directivity of the receive antennas, there is essentially no multi-path to contend with from satellites.  The main issue for satellite rf signals is very low signal strength at the receive antennas. Terrestrial rf transmission is the worst possible rf environment.   It must deal with multi-path, RFI, and weak signals and still deliver a perfect DTV picture.

Here in Cuba our national television uses the highly efficient DTMB’T that has proven to be more reliable than the ATSC systems variants used in the USA. So far Cuban radio amateurs have used analog Television transmissions using several slow scan TV modes that proved to be very effective sending still photos of hurricane affected areas to the Civil Defense command posts using both 2 meters FM and HF single side band transmissions.

This is Radio Havana Cuba, the name of the show is Dxers Unlimited. I am your host Arnaldo, Arnie Coro and here is our next radio hobby related item for today… it is about the really amazing results achieved by minimalist amateur radio stations, using minimum parts counts receivers and transmitters…

Starting with dual triodes tubes in a glass envolope the regenerative receiver was designed to work on the 40 meters amateur band, using high impedance headphones . The first triode is the detector and the second one works as an audio amplifier… The radio tunes from 7000 to 7150 kiloHertz only. It has good sensitivity and uses very common electronic parts that you can find by recycling equipment…

It uses a low voltage power supply that is also easy to build… The transmitter first option uses quartz crystal control and a single power tetrode or pentode vacuum tube, that when fed from a voltage doubler power supply will easily provide between two and five watts into the simple half wave coaxial fed dipole antenna. When a local amateur that is a QRP low power radio enthusiast saw the minimalist station he said, and I agreed with him, that it is a simplified version of the famous World War II Paraset !!! He took the circuit diagrams and photos to duplicate the set.

And now at the end of the show…. Arnie Coro’s HF propagation update…. Zero sunspots … a blank solar disc with very low solar activity …AND A GEOMAGNETIC STORM IN PROGRESS: As predicted, a moderately strong G2-class geomagnetic storm was underway on Sept. 11th as a stream of high-speed solar wind buffets Earth’s magnetic field. This morning in Alaska, “amazing auroras covered all of the sky,” reports Ayumi Bakken from just outside Fairbanks.

Send your signal reports and comments about this program to inforhc at enet dot cu or Via Air Mail to Arnie Coro , Radio Havana Cuba, Havana, Cuba.


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Links To Relevant Hurricane Florence Information and Traffic Nets

11 September 1000 EDT

For up-to-date information on Hurricane Florence, please check out these links:

– Hurricane Watch Net –

– VOIP Hurricane Net –

– Amateur Radio at the National Hurricane Center –


– ARRL –

Obviously do not interfere with emergency and informational traffic provided by these sources.


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Amateur Radio Images From The Chinese Satellite Orbiting The Moon

An interesting story about the recent launch and the satellite itself. More about downloading images can be found on the AMSAT Twitter page both US and UK versions

Chinese lunar mission and amateur radio


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Dxers Unlimited mid week edition for Tuesday  4 Sept 2018

By Arnie Coro
radio amateur CO2KK

Hola amigos radioaficionados all around the world.. this is Dxers Unlimited’s middle of the week edition with yours truly Arnie Coro as your host.. Here is now news item one… a very interesting report

DXCC COUNTRY/ENTITY REPORT: According to the AR-Cluster Network for the week of Sunday, 26th-August, through Sunday, 2nd-September there were 213 countries active. And I guess that this good results have something to do with the FT8 digital communications mode now in use around the world making possible two way contacts under extremely poor propagation conditions…

The South African Radio League (SARL) say the past weekend, Radio Amateurs reported that they experienced periods of radio black-out which lasted 24 hours.

When a strong enough solar flare occurs, ionisation is produced in the lower, more dense layers of the ionosphere (the D-layer), and radio waves that interact with electrons in layers lose energy due to the more frequent collisions that occur in the higher density environment of the D-layer. This can cause HF radio signals to become degraded or completely absorbed. This results in a radio blackout, the absence of HF communication, primarily impacting the 3 to 30 MHz band.

HamSci (Hamradio Science Citizen Investigation) is a USA based group of radio amateurs and scientists who work together to study various aspects of radio science. During this weekend’s event they found that the solar and the planetary field united and created a hole that let plasma inside the magnetosphere of the planet create severe auroras.

The fast-growing sunspot (AR270) has a reversed polarity which would link it as the first sunspot of the next solar cycle. The solar cycle is an average of 11 years. The current cycle (cycle 24) still has approximate 2 years to go before it is expected to reach its minimum and cycle 25 to start. The question HamSCI is asking was this just a single event or are we truly entering cycle 25?

Whatever hit Earth was not proton flux which is associated with CMEs and coronal holes. The storm was created by fast compression of earth’s magnetic field and the sudden release of magnetic pressure from the Sun. This whiplash created a vacuum which sucked in the plasma surrounding the planet and at the same time caused the geomagnetic activity to rise to a G3 strong storm level. Other sources are forecasting a much earlier than expected solar minimum, making cycle 24 one of the shortest on record.

Espeleologists, the scientists that do research about caves and caverns make use of a transceiver known as the HeyPhone that is a 17-year-old design from British radio amateur John Hey, G3TDZ who passed away some time ago so he didn’t get to see his design play a role in the most recent high profile cave rescue that took place in Thailand, although it has apparently been a part of many others in the past. The HeyPhone is actually considered obsolete but is still in service with some  espeleology teams.

The radio uses USB upper sideband voice operating at the very low frequency of  87 kHz. The low frequency can penetrate deep into the ground using either induction loop antennas like the older Mole-phone, or — more commonly — with electrodes driven into the ground to inject RF energy directly into the surrounding area. What is interesting is that in today’s world, people take wireless communications for granted and don’t realize that cell phones don’t work underground or in the face of wide-spread disasters when the cell towers fail or the cell system is overloaded with traffic that it can not handle.

More solar cycles predictions and forecast now circulating …. one of the latest ones says that cycle 25 is now coming to an end… after only 10 years of evolution… Another source assures that reverse magnetic polarity sunspots located at the less active hemisphere of the Sun during cycle 24 are almost surely the precusors of solar cycle 25…

Here is the latest report from the very realiable Spaceweather site: reported new sunspot group 2720 is the first large spot of the next solar cycle, Cycle 25. The magnetic polarity is reversed from the polarity of sunspots in Cycle 24. Whatever is happening 93 million miles away from Earth is going to be quite clear as time goes by. In the meantime adjust your radio hobby operating habits and technologies for monthly sunspots counts of less than 10 for quite some time ahead….

SI amigos you are listening to the middle of the week edition of Dxers Unlimited the radio hobby program covering the more than 93 ways of enjoying our spare time playing with radios, antennas and software. Amateur radio satellites use frequencies that are supposed to be dedicated to that service… Recently, on August 27th, AMSAT Vice President of Operations Drew Glasbrenner, callsign KO4MA, noted:

“Recently there has been a DMR signal QRMing the AO-92 satellite uplink on 435.350 or close by. Hotspots, repeaters, terrestrial simplex (anything not satellite) should not be in 145.8-146.0 or 435-438 by international bandplan.” He requests ground stations using those frequencies to please QSY, move these away from the satellites uplink frequencies. Possible sources of those signal include ease share to DMR, D-star, Fusion, P25 groups and similar terrestrial amateur radio activities.

Again the segments of two meters and seventy centimeters that are to be protected from ground based stations not intended to communicate via satellite are in the 145.8-146.0 segment of two meters and  435-438 Mhz amateur satellite subbands.

It happened 159 years ago…. and scientists are talking about the extraordinary geomagnetic storm that it caused known as the ¨ Carrington Event ¨

159 years ago: planet Earth was hit by a geomagnetic megastorm. On Sept. 2, 1859, a powerful CME rocked Earth’s magnetic field, causing a geomagnetic storm that set fire to Victorian telegraph offices and sparked auroras as far south as Mexico and Cuba. Now known as the “Carrington Event,” that megastorm 159 years ago is a touchstone of modern extreme space weather research. What are the odds it could happen again? The cause of all this was an extraordinary solar flare witnessed the day before by British astronomer Richard Carrington. His sighting on Sept. 1, 1859, marked the discovery of solar flares and foreshadowed a new field of study: space weather. According to a study by the National Academy of Sciences, if a similar “Carrington Event” occurred today, it could cause substantial damage to society’s high-tech infrastructure and require years for complete recovery. Could it happen again? The answer is : Almost certainly. In a paper published just a few months ago, researchers from the University of Birmingham used Extreme Value Theory to estimate the average time between “Carrington-like solar flares.” Their best answer: approximately every 100 years. In other words, we may be overdue for a really big storm.

AM medium wave broadcast band Dxing propagation conditions will see an improvement as we approach the autumn equinox… Look for stations from the  Bahamas… there are just three AM stations operating from the Bahamas…

The three are rather easy to log all along the East Coast of North America starting with station, ZNS3, on 810 kiloHertz, from Freeport, Grand Bahama. Described as the Northern Bahamas Service. On 1540 kiloHertz ZNS1 from Freeport Grand Bahama Island runs higher power, while ZNS2 from Nassau, New Providence Island operates on 1240 kiloHertz…

And now amigos, at the end of the show , here is Arnie Coro’s HF propagation update and forecast… Solar activity is at very low levels with daily solar flux figures near the minimum values ever registered since 1947, when solar radio astronomists started to monitor the Sun’s solar flux on the 10,7 centimeters wavelength…..

As all of you are familiar with the close ties between solar flux and HF bands propagation conditions…. it is quite evident that we are going through a period of very poor propagation within the 3 to 30 megaHertz range.

See you all at the weekend edition of Dxers Unlimited and don’t forget to send me 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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