Monthly Archives: April 2021

Guest Post: A visit to Museo Marconi in Villa Griffone, Pontecchio, Bologna


Many thanks to SWLing Post contributor, Ferruccio Manfieri (IZ1096SWL), who shares this report and excellent photo tour from a visit to the Museo Marconi in Bologna, Italy in 2018.

Today is International Marconi Day, so this is a very welcome, and timely post:


A visit to Museo Marconi in Villa Griffone, Pontecchio, Bologna

by Ferruccio Manfieri (IZ1096SWL)

Bologna, in Northern Italy, is renowned to be the seat of the oldest University in Europe and in the world (the Alma Mater Studiorum) and its historic, artistic and culinary heritage. From a scientific perspective, Bologna is the birthplace of Guglielmo Marconi as well as the place of his first experiments in transmission.

The inventor, born in Bologna on April 25th, 1874, was the son of an Italian father (Giuseppe, a wealthy landowner) and an Irish mother (Annie Jameson, of Jameson’s Whiskey family). At the age of 20, Marconi began to conduct experiments in radio waves, building much of his own equipment in the attic of his home at the Villa Griffone in Pontecchio (in the Bolognese countryside).

Marconi received his final resting place in Villa Griffone Mausoleum, an enterred crypt hosting his porphyr sarcophagus. The building was donated to the Guglielmo Marconi Foundation in 1941 after the  death of the inventor (on the 20th of July 1937).

Sadly, Villa Griffone and the Mausoleum suffered heavy damages from WWII bombings and pillages and were patiently rebuilt in post-war years. Today, Villa Griffone is reborn as a hub of research and divulgation activities, hosting Guglielmo Marconi Foundation, the Marconi Museum, a library and two research groups on communication systems.

On the 26th of april 2019 I visited with my family the Museum hosted in the original building (a short trip from Bologna, 20 minutes by public transport)

Villa Griffone and the Marconi Mausoleum

The visit began with a nice stroll in the Villa gardens, home with the nearby hill of the Celestini of the first long-range and not in line of sight transmission experiment in 1895. Marconi managed to send signals over a distance of 2 km, beyond a hill situated between the transmission equipment (to which he had added a grounded vertical antenna) and the reception apparatus (characterised by an extremely sensitive coherer).

Villa Griffone gardens and “Hill of Celestini”

We were in the very spot Marconi was when he transmitted his three signals to the receiver operated by his brother and the gardener behind the hill. Nearby, the replica of eight meter wooden pole with the attached metal boxes used as antenna.

Marconi’s first “long range” antenna – replica

This experiment in universally aknowledged as the birth of radio transmission (and, by the way, the rifle shot used as a confirmation of the reception was the very first QSL…).

Our valent host and guide to the visit was the Director of the Museum, Barbara Valotti, who thoroughly described us (with knowledge, passion and communication skills) the historical framework of Marconi’s biography and works. A more engineering oriented and hands-on visit to the working replicas laboratory was subsequently hosted with passion and knowledge by Adriano Neri I4YCE.

In the Auditorium Dr. Valotti  showed us two videos on the first transmission experiment and on the Republic incident in 1909, on of the first application of Marconi radiotelegraphy in an incident at sea, whose success (no lives were lost in the aftermath of the collision thanks to the coordination of rescue efforts via radiotelegraphy) gave a boost of popularity to radiotelegraphy and to the engineer, eventually leading to the Nobel prize in physics later that year.

A frame of the “Republic” video

This part of the visit emphasized his interest in real technological applications of his inventions and their commercial potential. Marconi was a “modern” mix of engineer (with an unhortodox, non-academic formation) and entrepreneur, ready to see the new potential applications of technologies in the society.  Interestingly, Dr. Valotti underlined that the main focus of Marconi research was always the point-to-point trasmission and not the broadcast.

Hanging on the ceiling of the auditorium, a replica of the kite used by Marconi to lift an emergency antenna in the first transoceanic transmission from Poldhu to St Johns Newfoundland in 1901.

Yacht “Elettra” – memorabilias

The visit continued to the “silkworm room”, the original room (once used to breed silkworms) where Marconi held his laboratory and performed his experiments. The room was full of instruments replicas to show the laboratory as in the young Marconi years.

“Silkworm room” – Marconi’s first laboratory (original place,  instrument replicas)

“Silkworm room” – Marconi’s desk (replica)

It was also possible to replicate the main experiments with educational working replicas.

Marconi transmitter – educational replica

Headphone and coherer used in the first transoceanic transmission (replicas)

The second phase of the visit was a more engineering-oriented explanation of the principles of radio telegraphy conducted by Adriano Neri I4YCE in a didactic laboratory on working replicas of the main epoch instruments.

Experiment table with working replicas: coherers, a wire decoder, a Marconi receiver

Instruments in the educational laboratory

With passion and competence, Mr. Neri explained us in a simple way (there were some very interested young people in the group) the cable telegraphy principles and the sequence of experiments and discoveries that led Marconi to his inventions.

In a detailed and fascinating exposition we saw applications of a Morse writer, the induction coil, the coherer and the first Marconi spark transmitter, all assembled in the end to transmit in the room some morse signals in the air.

Live demonstration of signal transmission by Adriano Neri . Against the wall a Marconi spark transmitter (note the antenna and ground plates), on the table: a Marconi receiver (with a coherer) connected with a Morse writer.

The laboratory, as the whole museum, hosts a huge number of working replicas (a wonderful collection in itself, handmade by Maurizio Bigazzi with rigorous standards of adherence to the original designs and, if possible, reuse of original parts) and some original equipment.

Ship wireless telegraph room – working replica

A last section of the museum is devoted to radio communication during the war (showing a WWI airplane-ground communication system) and radio broadcasting, with original sets of great interest like a 1923 Marconiphone (still working, we had a live demonstration receiving RAI programs) and a Ducati radio (the same Ducati company of motorbikes, based in Bologna).

WWI plane radio and ground receiver

1923 Marconiphone, working original set

Ducati radio

We spent all the morning in the Museum with great fun and interest from all the family.

I highly recommend a visit to the Museum for the place,  its significance in the history of radio transmission and the competent and passionate exposition of the historical and technical themes related to Guglielmo Marconi.

A wealth of information (also in english) can be found of the Guglielmo Marconi Foundation website (www.fgm.it).

A detailed gallery of the Museum can also be found on the new Museum website (www.museomarconi.it)

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Dan Robinson reviews the Sangean ATS-909X2

Many thanks to SWLing Post contributor, Dan Robinson, for the following guest post and review:


Sangean v Tecsun in the Battle of Late Shortwave Era Portables:  The ATS909x2

by Dan Robinson

Some years ago – actually more than a decade – I decided to give Sangean a shot at winning me over in the shortwave portable category.

I had and still do use numerous portables with a bias toward the classic SONY, Panasonic, and Grundig sets.  The ones that made an impression stayed, often in multiples, as anyone can see if they visit the radio shack here in Maryland.

These include, for those interested:  the Panasonic RF-B65, SONY ICF-SW77, ICF-2010, ICF-PRO80, ICF-7600D, ICF-7700, ICF-SW1000T, ICF-SW55, ICF-SW100s, ICF-SW07, Grundig Satellit 500, to which were added in more recent times the Toshiba  RP-F11, XHDATA D-808, and Tecsun portables ranging from the PL-365 and new PL-368 to the PL-880, PL-990x, H-501x, and S-8800.

Sangean has generally not been on that list. There’s a good reason – I just never considered Sangean to be competitive when it comes to portables, though they did have some excellent larger sets such as the ATS-803A that made the first forays into multiple bandwidth options.

My last experience with Sangean was with the ATS-909.  I liked the looks and capabilities of that receiver, and even went to the point of having mine modified by Radio Labs.  But those mods were underwhelming, in my view, and the original 909 always seemed to me to be deaf when using the whip antenna.

That issue continued unfortunately with the 909x.  Some of you may have seen a video I did a few years ago in which I set a 909x against a SONY SW-07 and Panasonic RF-B65.  This was done barefoot with only the whip antennas, but near a window.  In short, the other two radios wiped the floor with the 909x.

It took a surprisingly long time for Sangean to update the 909x with the 909×2, during which companies asked valid questions about the need for further development of world band portables.

Eton turned the market on its head when it introduced the still superb E1/XM which competed with the very end of SONY portable production, and co-designed with R.L. Drake added such superb features as Passband Tuning and three selectivity positions.

Meanwhile, Tecsun plugged away, introducing an impressive array of portables including the PL-600 series, then the 880 and now the 990x and H-501 portables.

So, now the 909×2 is here and with its 073 firmware upgrade has become a bit of a holy grail for portable receiver users.  There have been a number of excellent reviews, including Dave Zantow’s deep dive, and some others here on SWLing Post.

I’m going to give you my impressions, using the really detailed Zantow review as a base.  I received my 909×2 from Amazon just today – it is a 073 firmware which confirms that new supplies have the upgrade.

SENSITIVITY ON WHIP

First, let’s get the elephant in the room out of the way.  Although I have not undertaken detailed technical testing of the 909×2 – nor do I have the equipment to carry this out – it does seem that Sangean may have finally tackled this crippling flaw that rendered the old 909x nearly useless when using it only on the whip.  I’ll undertake further testing and comparisons with some of my other portables to confirm this.  The whip antenna itself is robust – solid and long, something that Tecsun could take note of.

AIR BAND

Inclusion of air band on this radio is a major selling point for those interested in this type of monitoring.  My initial tests showed the 909×2 to be quite sensitive and useful – I managed to pick up no fewer than five airport comms frequencies in my area here in Maryland.

SELECTIVITY / AUTO-BANDWIDTH

The 909×2 really shines with FIVE available selectivity options that are easily selectable in shortwave mode.  It would have been nice to be able to actually see the values of each filter as one scrolls through, but that’s a minor point.  Think about it – in shortwave AM mode, this is the number of selectivity positions that one finds on such power house communication receivers as a Drake R8.  Amazing that we now have that in a portable.  On the negative side, I find the auto-bandwidth feature on the 909×2 to be nearly useless, as useless as the similar feature found on Tecsun receivers. The automatic switching is distracting and annoying. My advice to users: forget this, and stick with manual bandwidth control.  My advice to Sangean – I wish they had left this feature out but given us multiple bandwidths in SSB.

LCD AND BRIGHTNESS

Sangean hits it out of the park with this multi-stage lighting for the display.  Simply superb and the kind of quality we could only hope for from other manufacturers.

MAIN TUNING / DETENT CONTROL

I found the detents on the old 909x to be annoying – indeed, modifications have been available that could remove this feature.  But Sangean being Sangean, the detent wheel remains in the 909×2 and it is not a deal killer.

AUDIO QUALITY

The radio retains the excellent audio of the 909x – I am not sure the 909×2 exceeds what one hears from a Tecsun 990x or H-501x but it’s right up there and competitive.

POWER SUPPLY

As others have noted, thanks to Sangean for sticking with AA cells.  Together with internal charging when using Ni-Mh cells this is a major selling point.  On the other hand – competitor Tecsun went a step farther with its H-501x which though it uses 18650 lithium batteries, has dual batteries, one of which can be held in standby, and switchable charging.  That’s a design feature that you really have to respect.

VARIABLE RF GAIN

Again, as noted by others Sangean retained the extremely useful thumb wheel RF gain control.  This is an excellent feature.

KEYPAD

Another home run for Sangean when it comes to the keypads on the 909×2, which can be compared in this respect to the Tecsun H-501x which itself improves upon the 990x when it comes to front panel control.  Time will tell, however, and we shall see if the keys on these radios hold up in heavy use.

UP/DOWN SLEWING

These controls which sit outside the circular main tuning knob are excellent, and reminds one of the slewing buttons on the SONY 7600GR, SW1000T and SW100.

S-METER / DISPLAY

RSSI and SN Digital Signal Strength Information are provided on the beautiful 909×2 display.  This is an improvement over the Tecsun signal strength/SNR meters that I wish would be redesigned, if in fact Tecsun has any intention of future modifications to their portables.

NO SOFT MUTING

Thank goodness we don’t have to deal with the annoying soft muting issue that is still seen in some other portables (the XHDATA D808 comes to mind along with the Eton Executive).  Soft muting quite simply ruins a listening session and it’s baffling that any manufacturer still puts it in.

NEGATIVES (I AM IN TEARS)

OK, close all airtight doors and prepare to dive!  Here are the negatives I see with the 909×2.  I held off obtaining one of these radios because I knew there would be issues.  And I was disappointed enough in the past with the 909x and 909 before it that I had almost decided not to go for it.

SIGNS OF LONGWAVE RECEPTION PLAGUED BY CROSS-MOD FROM MEDIUMWAVE 

On my particular unit – it remains to be seen whether this is true for others – long wave seems to be near useless.  The band is filled with mediumwave stations bleeding through.  Turning down the RF obviously helps but I still hear AM stations here in the DC area, when I am in LW mode.

SSB PERFORMANCE

ALERT FOR SANGEAN AND ALMOST A DEAL BREAKERas mentioned in the Zantow review, and in other comments I have seen on the 909×2, the drop in level from AM to LSB is a killer negative.

This is less noticeable in MW.  But if you are in shortwave and have turned your volume up on any particular station, say a strong one such as Greece on 9,420 kHz or Spain, or an AM station, and you then switch to LSB it is like you have almost lost the signal.  This simply needs to be fixed.  Level on USB seems fine and acceptable, but LSB on shortwave requires immediate upwards adjustment of volume, only to have to reverse the process when returning to AM mode.  I find this problem to be sufficiently serious that I would recommend against obtaining a 909×2 until Sangean finds a way to fix it.  This issue is on the same level of BAD as the still unsatisfactory SYNC mode in all three of Tecsun’s shortwave portables.  In fact, I may return the 909×2 I obtained and wait until a fix for this emerges.

Example Video

In this video, I demonstrate the extent of the problem as seen on this particular unit of the 909×2, which carries a serial number dk201043181.

Dave Zantow says his unit does not have this issue, so there is a possibility this is due to unit to unit variation. As you can see, with a strong signal such as 12,160 kHz — switching from AM to LSB instantly reduces listenable level, and signal as measured on the 909×2 drops to zero bars or near zero. In USB, the reduction is less severe. Regardless, having to perform adjustments with main volume just to struggle to hear any signal in SSB is a bit ridiculous. This kind of thing is not seen on the Tecsun H-501x or 990x though as Dave correctly points out, Tecsun receivers are not exactly great performers in SSB. On Tecsun receivers, there is a slight processor pause while the receiver makes the switch into LSB or USB, without the sharp reduction in listenable level.

CALIBRATION ISSUES WITH NO WAY TO ADJUST

Imagine my joy when I first began using the x2.  Initially, it seemed to be smack on frequency – I tried this on WMAL, the powerhouse local AM station here in the DC area, and then again with stronger stations on shortwave, such as 12,160 kHz.  Ah, I said to myself, Sangean has some decent QC and paid attention.  About 30 minutes later, however, what I found matches the Zantow review.  Stations are consistently low of the tuned/displayed frequency by as much as 300 Hz.  The reason this is so disappointing is that I feel Sangean could have taken a clue from Tecsun and provided a re-calibration function (unless it exists and we aren’t being told about it).  On Tecsun radios, the re-calibration capability is the major counter-punch to poor synchronous mode – in my view, one can live with flawed SYNC on a 990x or H-501 or PL-330 as long as you can adjust and at least have zero beat or close to it across frequencies.  At the same time, as Zantow points out, no one should be expecting TCXO level performance from portables such as these.  However, it is a bit disappointing that after all these years and redesign of the 909x to add some really nice features, they’re still landing up to 300 Hz from a tuned frequency.  On the other hand, is this really any worse than one would see from an off-tuned SONY ICF-2010?  No, and adjusting those older receivers required surgery.

CONCLUSIONS

I really like the 909×2.  There simply is something about this design that Sangean knew was a winner when it first arrived on the market years ago, so it’s not surprising that Sangean stuck with it.  It’s clear that some hard thinking went into the step up from the old 909x, notably the larger LCD, addition of finer step tuning to make SSB easier, the robust antenna and the still pretty darn good audio through the wonderful speaker.  The 909×2 is a radio that you can imagine guests would comment on if it were sitting on your coffee table – it just looks THAT GOOD.

But then here in 2021, so does a Tecsun H-501x LOOK THAT GOOD.  As I noted above, where the Tecsuns fall down – with their still challenged synchronous mode – they make up for with the ability to re-calibrate.

That is a huge feature and one that Sangean struck out on, though surely Sangean designers had to know the 909×2 would appeal both to listeners and to hobbyists with obsessions about frequency accuracy.

To repeat, I really (really) like the 909×2.  But another area where the receiver strikes out is the problem with sharp reduction in LSB mode.  Seriously – you have to crank the volume control up to at least 50 percent to hear ANYTHING when you’re in LSB, whereas USB requires going only up to about 30 percent.  Then when you’re completing your carousel back to AM, you have to be sure not to still have the audio up at 50 percent or more to avoid blowing your speaker.

Again, as I said above, the calibration/drift issue on the 909×2 can be lived with.  The problem with LSB, in my opinion, cannot or should not be tolerated.  So, the question is, do you want to purchase a 909×2 now that still has that LSB audio issue, or wait a while until Sangean gets its act together?

These and other earthshaking questions are before us here in 2021.  We have some of the best portables ever made by anyone in a time of sharply declining shortwave use, but they each have their flaws.

I don’t usually do a star rating or RECOMMEND / NOT RECOMMEND for radios.  This time, I am going to make an exception and it links directly to the issue of the LSB problem on the 909×2.  These radios simply should not have been allowed to enter the market with this being as serious a problem as I think it is.  For that reason, I honestly cannot recommend a Sangean 909×2 until this is corrected.

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Radio Waves: Josh reviews the Belka-DX, Sinclair Fraunhofer DRM Partnership, Clear Net Frequencies Requested, and

Radio Waves:  Stories Making Waves in the World of Radio

Because I keep my ear to the waves, as well as receive many tips from others who do the same, I find myself privy to radio-related stories that might interest SWLing Post readers.  To that end: Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!

Many thanks to SWLing Post contributors TomL, Alan, Bruce Atchison, and Troy Riedel for the following tips:


Belka DX Shortwave Receiver – Closest Thing To A Spy Radio? (HRCC via YouTube)

Sinclair Launches ATSC 3.0 Test Site; Partners With Fraunhofer On Mondiale Service Integration (ATSC)

HUNT VALLEY, Md.—Mark Aitken, senior vice president of advanced technology at the Sinclair Broadcast Group, flipped the switch on a 100w transmitter to begin broadcasting ATSC 3.0 from atop the station group’s corporate headquarters here with the express purpose of testing reception on small devices like its MarkONE 3.0-enabled smartphone and, in particular, integration of Digital Radio Mondiale (DRM) in its broadcast app.

The launch comes on the same day Sinclair and German technology research institute Fraunhofer IIS jointly announced they are working together to bring audio services using the DRM standard to ATSC 3.0. (Earlier this year, Sinclair rolled out 3.0 simulcasts of its Seattle radio stations with its DRM-based broadcast app.)

“We are actually building the DRM radio service into the [3.0] broadcast app environment,” says Aitken. “That means those [DRM] services will be carried in band and transported just like HEVC [high efficiency video coding] and [Dolby] AC-4.”[]

Clear Frequencies Requested for Net Providing 24/7 Coverage of St Vincent Volcanic Eruption (RAC Newsletter)

For immediate release:
April 20, 2021 –

The Caribbean Emergency and Weather Net (CEWN) has been providing round-the-clock coverage during the La Soufriere volcanic eruption on the island of Saint Vincent and the Grenadines.

Several neighbouring islands are also being affected by the disaster.

When responding to disasters and emergencies such as this, the CEWN utilizes 3.815 MHz LSB and 7.188 MHz LSB. CEWN is requesting that Radio Amateurs not involved in the volcano response to keep these frequencies clear.

Geomagnetic storm warning (Spaceweather.com via Southgate ARC)

A CME is heading for Earth and it could spark a geomagnetic storm when it arrives on April 25th.

NOAA forecasters say moderately strong G2-class storms are possible, which means auroras could dip into northern-tier US states from Maine to Washington.

Full story and updates @ Spaceweather.com.

 


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International Marconi Day: Special Edition of the International Radio Report

Many thanks to SWLing Post contributor, Sheldon Harvey, who shares the following:

If you are a regular listener to the International Radio Report on Sundays on CKUT FM 90.3 in Montreal, or if you catch it on the CKUT archives or, more recently, on our new YouTube channel, you’ll want to know that we have just posted to the YouTube channel our first “Special Edition” of the show today, April 22nd 2021. Special events are happening this coming Saturday that we would not have been able to tell you about any other way, so we created this special edition. Saturday is International Marconi Day, with a number of special events ham radio stations on the air throughout the day, including a ham station from the Vatican, where Marconi’s daughter will be one of the guest ham operating on the microphone. You can find the YouTube special edition of our program at International Radio Report Special edition International Marconi Day 2021.

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Giuseppe is impressed with the performance of his homebrew passive loop antenna

Many thanks to SWLing Post contributor, Giuseppe Morlè (IZ0GZW), who shares the following:

Dear Thomas, I’m Giuseppe Morlè from central Italy, the Tyrrhenian Sea, Formia.

Today I tested my noise canceling loop inside the radio station by comparing it to the crossed loops. Again, like my medium wave T Ferrite, this loop proved to be very quiet, practically immune to house noise.

You can see my two videos about listening to the Voice of Turkey and a QSO on 40m. between radio amateurs–a test with two different powers, one high in AM and another much lower among radio amateurs.

Here are the videos from my YouTube channel:

Click here to view on YouTube.

Click here to view on YouTube.

A nice result knowing that we are receiving inside my radio station. The homebrew NCPL antenna you encouraged me to build is truly amazing.

Best wishes to you and the SWLing Post community.

73 by Giuseppe Morlè IZ0GZW.

Thank you so much for taking the time to share your thoughts and these videos with us, Giuseppe. It is very encouraging that we have some antenna options that help us cope with all of the RFI generated within our homes! Thank you again!

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FTIOM & UBMP, April 25-May 1


From the Isle of Music, April 25-May 1:

This week, we listen to several recordings by guitarist Elmer Ferrer.
The broadcasts take place:
1. For Eastern Europe but audible well beyond the target area in most of the Eastern Hemisphere (including parts of East Asia and Oceania) with 100Kw, Sunday 1500-1600 UTC on SpaceLine, 9400 KHz, from Sofia, Bulgaria (1800-1900 MSK)
2. For the Americas and parts of Europe, Tuesday 0000-0100 UTC on WBCQ, 7490 kHz from Monticello, ME, USA (Monday 8-9PM EDT in the US).
3 & 4. For Europe and sometimes beyond, Tuesday 1900-2000 UTC and Saturday 1200-1300 UTC on Channel 292, 6070 kHz from Rohrbach, Germany.
Our Facebook page is https://www.facebook.com/fromtheisleofmusic/
Our V-Kontakte page is https://vk.com/fromtheisleofmusic
Our Patreon page is https://www.patreon.com/tilford

Uncle Bill’s Melting Pot, April 25-May 1:
In episode 214, we listen to some Jamaican mento and calypso.
The transmissions take place:
1.Sunday 2200-2300 UTC  (6:00PM -7:00PM EDT) on WBCQ The Planet 7490 kHz from the US to the Americas and parts of Europe
2. Tuesday 2000-2100 UTC on Channel 292, 6070 kHz from Rohrbach, Germany for Europe.
3. Saturday 0800-0900 UTC on Channel 292, 9670 kHz from Rohrbach, Germany for Europe with a directional booster aimed eastward.
Our Facebook page is https://www.facebook.com/UncleBillsMeltingPot/
Our V-Kontakte page is https://vk.com/fromtheisleofmusic
Our Patreon page is https://www.patreon.com/tilford

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Radiofax images of Typhoon Surigae from the Japan Meteorological Agency

Many thanks to SWLing Post contributor, Carlos Latuff, who writes:

Technology considered obsolete, the fax, or better, radiofax (transmitted by radio) continues to be used by several meteorological agencies around the world, which broadcast weather charts to vessels on the high seas. These two images were transmitted today by the Japan Meteorological Agency and received at 19h10 and 19h50 (UTC) in Porto Alegre, Brazil.

The first image is a photo from the Japanese satellite Himawari 8. Even with noise, due to the shortwave propagation, you can see clearly the “eye” of typhoon Surigae.

The second image is a typhoon alert, indicating on the map that Surigae has changed course and is now en route to the Pacific.

These two images were transmitted today by the Japan Meteorological Agency, on the frequency of 7795 kHz

Thank you for sharing this, Carlos. It’s amazing, the amount of information you can receive over the air even with modest equipment by today’s standards. With a modest portable radio and a little decoding software, anyone can grab images like this.

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