Podcast dives into world of Cold War Numbers Stations

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Many thanks to SWLing Post contributor, Ulis, who shares a link to the following episode of the Cold War Conversations podcast which focuses on numbers stations:

Cold War number stations

You might remember listening to short wave radio during the Cold War and coming across weird transmissions of metallic voices reciting random groups of numbers through the ether. These are number stations, shortwave radio stations characterised by broadcasts of formatted numbers, which were being sent to spies operating in foreign countries.

Number stations were used widely during the Cold War and we speak with Jo Reggelt of ShortwaveNumbers.com. Jo has been working with Simon Mason who was a founding member of ENIGMA, launched in the 1980’s after identifying several of these stations.

We discuss in detail the operations behind the transmissions and the stations themselves. You will hear some sample transmissions, including one of drunken Stasi officers serenading their agents after the opening of the Wall. [Continue reading…]

Click here to listen to this podcast on the Cold War Conversations website,
or via iTunes or Spotify.

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Radio Waves: Waves Around Earth’s Core, New Australian Communications Minister, Shipping Forecast Future, and Hams Accused of Being Spies

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Radio Waves:  Stories Making Waves in the World of Radio

Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!

Giant Magnetic Waves Have Been Discovered Oscillating Around Earth’s Core (Science Alert)

Earth’s interior is a far from quiet place. Deep below our surface activities, the planet rumbles with activity, from plate tectonics to convection currents that circulate through the hot magmatic fluids far underneath the crust.

Now scientists studying satellite data of Earth have identified something inside Earth we’ve never seen before: a new type of magnetic wave that sweeps around the surface of our planet’s core, every seven years.

This discovery could offer insight into how Earth’s magnetic field is generated, and provide clues of our planet’s thermal history and evolution – that is, the gradual cooling of the planetary interior.

“Geophysicists have long theorized over the existence of such waves, but they were thought to take place over much longer time scales than our research has shown,” says geophysicist Nicolas Gillet of the Université Grenoble Alpes in France.

“Measurements of the magnetic field from instruments based on the surface of Earth suggested that there was some kind of wave action, but we needed the global coverage offered by measurements from space to reveal what is actually going on.

“We combined satellite measurements from Swarm, and also from the earlier German Champ mission and Danish Ørsted mission, with a computer model of the geodynamo to explain what the ground-based data had thrown up – and this led to our discovery.”

Earth’s magnetic field is the subject of much fascination for scientists. Research to date suggests that the invisible structure forms a protective ‘bubble’ around our planet, keeping harmful radiation out and the atmosphere in, thus allowing life to thrive. [Continue reading…]

Michelle Rowland sworn in as new Communications Minister (TV Tonight)

Michelle Rowland sworn in as new Communications Minister

Australia has a new minister leading regulation in the screen sector.

Michelle Rowland M.P. has been sworn in as the new Communications Minister under PM Anthoyn Albanese.

Replacing Paul Fletcher, she has previously been shadow communications minister in opposition.

“It is an honour to be sworn in as Minister for Communications and to serve the Australian people under an Albanese Labor Government,” she said.

“This portfolio has the potential to further enable an Australia where connectivity and content enriches our quality of life, informs us, drives productivity and empowers us to fulfil our potential. I am dedicated to ensuring Australians, in our cities and regions, are united and connected. Now, let’s get to work” [Continue reading…]

‘A link across time’: how shipping forecast will outlast Radio 4 long wave (The Guardian)

Boats have not needed the broadcast for decades but radio bosses know nostalgia for it runs deep

Radio 4’s shipping forecast is a national institution, with millions of listeners reassured by the thought that, somewhere out at sea, British fishers are patiently waiting by their radios to find out whether there is a gale warning in Rockall or Cromarty.

Yet the announcement that Radio 4’s long wave signal will be shut down as part of the BBC’s latest cuts has left many wondering how the country’s fishing fleet will cope without access to the four-times-a-day updates.

The slightly less romantic reality, according to Mike Cohen of the National Federation of Fishermen’s Organisations, is that his members have not needed Radio 4 for decades. Modern fishers have far more accurate devices to warn them about the wind and rain: “Even the small 15-metre boats in Bridlington have satellite internet these days. I’ve had video calls from people in the middle of the sea.”

Yet that does not mean they are immune to the charms of Sailing By, the music that heralds the forecasts and was designed to help captains adjust their radios: “That theme tune is a link to other times, other people, other places. There’s as much a fondness among fishermen for that as there is for the rest of us.”

When the fishers’ trade body asked its members how they felt about the shipping forecast one said it “acted as a link across communities, a link across time”. Another added: “For us it is a bygone age but for many older folk it is a reassuring connection to the past.”

The BBC plans to end dedicated programming on its Radio 4 long wave frequency next year, which could mean the loss of two of the current four shipping broadcast updates. The early morning and late night forecasts will remain on FM, DAB and online broadcasts. But the loss of the long wave signal – accessible far from the British mainland – confirms they will essentially be nostalgia pieces, more about waking the nation up or lulling listeners to sleep. [Continue reading…]

Two Brits arrested in Albania as police accuse them of spying after seizing radio gear (Southgate ARC)

Two Britons were quizzed on allegations of espionage by officers at Tirana International Airport in Albania after police discovered sophisticated Kenwood radios in their luggage

Two Britons have been arrested by Albanian spooks and accused of spying after border police found radio transmitters in their luggage.

The pair were quizzed on allegations of espionage by officers at Tirana International Airport after they discovered sophisticated Kenwood radios in their luggage.

They told the officials they were IT engineers who were carrying the amateur gear to indulge their hobby while on holiday in Albania.

One suspect was registered as using a “ham radio” in the Tirana region on online profiles, which also say he specialises in “electronic warfare”.

Albanian police confirmed that they have opened a probe over allegations of “spy activities” and “espionage”.

A source said: “It’s highly unusual to be carrying this sort of equipment and even more strange for someone to be stopped and accused of being a covert agent.”

The two Britons were held on May 30 and then allowed to return to the UK. However they remain under investigation, police say. The electronic kit by Kenwood – which makes a range of cutting edge communication devices – was sent to the Albanian Criminal Laboratory for further examination.

You can read the full Daily Mirror article at
https://www.mirror.co.uk/news/world-news/two-brits-arrested-albania-police-27191861

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X-Raydio on Channel 292

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Hi all, Fastradioburst23 here reminding you about X-Raydio on Channel 292 this Sunday 12th June 2022 at 2200 utc on 3955 kHz. The broadcast will be a little different to the one on WRMI last weekend.

X-Raydio explores audio from unusual musical formats and features a piece on Bone Music by Stephen Coates from The Real Tuesday Weld and a couple of flexi disc mixs including one from Shane Quentin from The Garden of the Earthly Delights radio show on CRMK, Milton Keynes. Tune in for something different!

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New-In-Box Icom IC-R8500s on eBay

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Many thanks to SWLing Post contributor, John (KC8RZM), who writes:

Hi Thomas,

Don’t know if this is relevant to SWLing but maybe there’s others out there that might be interested in the following.

I always kicked myself not picking up one of Icom’s IC-R8500 receivers before Icom discontiued it. I know this wideband receiver has excellent reviews regarding its performance and this model was about the last of the old analog/superhet design before everything started to go SDR.

Previously, I’d thought about buying a second-hand unit, but have always been wary not knowing its past usage and prefer to buy new gear.

So was surprised to see sellers on ebay the other day listing new and unopened IC-R8500s.

One unit was listed at $2,000.00 but the seller reduced it to $1,800.00 so I snapped it up for my collection.

I think $1,800.00 is about the original price when Icom was still producing this model.

I noticed another seller offering new IC-R8500s for $2,000.00 and apparently has more than 10 available as I type this:

https://ebay.us/iUZGn5

Maybe some other SWLing readers might still wish to own a new IC-R8500 before they disappear for good. As I said, it’s the last in a long line of distinguished Icom superhet-based radios before the SDRs took over.

Best wishes,
John
KC8RZM

Many thanks for sharing this, John. I have never owned an IC-R8500, but I’ve heard it’s an excellent wideband receiver. The seller seems to offer a 30 day warranty and does indeed have a number of these in inventory. Looking through the seller reviews, they have a 97.6% rating with 1310 reviews; only one negative review in the past year. It seems they are based in Israel, but shipping is free (with normal custom delays, etc.). 

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High Speed A/D Conversion in 1965, with a Vacuum Tube!

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Many thanks to SWLing Post contributor, Mark (AE2EA), with the Antique Wireless Museum who shares the following:

This isn’t a SWL, or even a ham radio story, but it’s a nice technology story about a vacuum tube at the beginning of the digital age and near the end of the tube age, that I thought you might be interested in:

Click here to view on YouTube.

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Kostas explores an alternative to Morse Code that’s been used in prisons, with roots in ancient Greece

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Many thanks to SWLing Post contributor, Kostas (SV3ORA), for sharing the following guest post which originally appeared on his radio website:

TAP: A Morse alternative mode for the HAM, with no need for training

by Kostas (SV3ORA)

Introduction

The thinking of this new mode, came to me when someone posted that he quit the HAM hobby because he did not learn Morse code and he did not want to use computers to do the job for him. Some time I faced a similar situation and I believe many do one day or the other. So I thought that I had to do something about it. It is too bad people quit the hobby or missing the fun of the KEY operation, because of the obstacle of Morse code. No matter what CW operators that already learnt Morse might say, the fact is that Morse requires patience, continuous practice and most importantly time. After all military had dedicated courses on it in the past, so it must be more than true. These are things not all people can, or are willing to do. An alternative that gives the same pleasure like Morse and operates with the same techniques, but requires no training and time must exist. Meet the TAP mode!

Mode description

This mode has its roots to ancient Greece. You may read the article in Wikipedia for more information on the Polybius square. A form of it, was used in the previous century in was times, for in-prison communication. A modified version is presented here by me, that fits perfectly the HAM radio. This modified TAP code scheme, is dedicated to HAM radio and includes the numbers and the letter “k”.

This is all you need to know in order to send and receive TAP. It is easy to follow and easy to generate on paper. This is a 6 by 6 table, with the first six alphabet letters placed in the first line, the next six in the second and so on. After the alphabet ends, the numbers are put in the same manner. Thats it!

Sending TAP

It is better to describe the sending procedure with an example.
To send the letter “i” you send two dots (“i” is on the second row), wait a bit and then send 3 more dots (“i” is on the third column). In other words, you first count the number of rows where the letter exists, then wait a bit and then you count the number of columns where this letter exists. Before sending the next letter, leave a bit of more time, so as to distinguish that this is a separate letter and not the time between rows and columns. Thats it!

Try it now without any transceiver! Write the TAP table on a piece of paper (you do not need to write the row and column numbers), or read it from the website. Tap on your desk with your finger and send some words to the colleague near you. See how easy it is?

There are actually four spacings involved. The spacing between adjacent dots, the spacing between the row and the column, and the spacing between letters and the spacing between words. Follow the PARIS spacing, like Morse code does, if you intent to write a software for it. However, in practice, manual operators would need to consider just two spacings, the spacing between rows and columns and the spacing between letters. These are the most important. Just make the one bigger than the other and communication should be achieved without problems.

Receiving TAP

It is better to describe the receiving procedure with an example.
To receive the letter “i” you listen two dots (“i” is on the second row), then a short scilence time and then listen 3 more dots (“i” is on the third column). In other words, you first listen for a number of dots (this is the row where the letter exists), then sense the scilence and then you listen for the next number of dots (this is the column where the letter exists). The scilence time between two letters is greater than the scilence between rows and columns and this can be distinguished easily. Thats it!

Try it now without any transceiver! Write the TAP table on a piece of paper (you do not need to write the row and column numbers), or read it from the website. Put your coleague to sent you some TAP words and you should be able to decode them by counting the rows and columns in the TAP table.

A programmer that may need to implement the mode in software, should follow the PARIS spacing to distinguish the different parts of the code, as described above.

TAP advantages

Here are some advantages I can think, of TAP in comparison to Morse.

  • No training is required, start using it imediatelly, even by non-HAM people and kids. This probably is the greatest advantage and this is why most would want to use TAP in HAM radio.
  • The encoding/decoding square can be drawn easily, it is very easy to remember how to draw it.
  • Decoding by hardware or software means, becomes very easy, as there are no dashes to account for. Dot lengths can be anything and can be even varying from dot to dot, it does not matter.
  • All you count, is how many ON-states (taps) there are and the rough timing between them, to decide between a row-column or a letter. Because of this intependency from dashes, the code can be used on any means, radio, light, pipes, walls, desks etc.
  • If dot lengths are kept very short (up to the point where channel noise allows it), RF amplifiers can be pushed beyond their limits (due to limited duty cycle), or otherwise run cooler within their limits. There are some mediums, like light communication, where bright pulses of light can be produced easily (eg. xenon tubes), but not kept for duration and TAP is ideal on them.

TAP disadvantages

Here are some disadvantages I can think, of TAP in comparison to Morse.

  • Speed limit issues probably. TAP beginners achieve for sure faster speeds than Morse beginners. However, a trained Morse HAM, can achieve greater speeds with Morse.
  • Learning the table by heart, can be tricky in comparison to Morse. However war prisoners had tricks to learn by heart the 5×5 TAP  square.
  • Not known (yet) among the HAM community, like any new mode. Why not change that by let HAMs know about it?

TAP common points to Morse

There are some common points shared between TAP and Morse code.

  • Both are relatively slow modes.
  • Both are ON/OFF keying modes, efficient class-E amplifiers can be used.
  • Both share the same channel bandwidth and noise-related characteristics.
  • Both are human-oriented, although TAP does not require training. Both share the PARIS timing when implemented in software.
  • Both allow for the “joy of the KEY”. You send TAP with the same equipment as Morse.
  • Both are ideal for homebrew QRP, due to efficiency and transceivers simplicity.
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Testing the MFJ-1020C Active Antenna/Preselector

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By Jock Elliott, KB2GOM

Truth be told, I’ve been curious about the MFJ 1020C for a long time. Back when I wrote for Passport to World Band Radio, over a decade ago, I wondered if the 1020C was a worthwhile device, but then I had a big wire antenna outside connected to a communications receiver, so I didn’t worry so much about squeezing every last erg out of the signals I was receiving. As a result, I never experimented with an MFJ 1020C.

Now, however, I have a 50-foot indoor end-fed wire antenna connected to a Grundig Satellit 800, and I am constantly looking to improve the signal. Feeding the signal through a 9:1 unun and then through coax to the Satellit 800 has boosted the signal-to-noise ratio a bit — https://swling.com/blog/2022/05/the-satellit-800-the-tecsun-pl-880-and-two-indoor-antennas-an-afternoon-of-experimentation/ —  and so has grounding the unun — https://swling.com/blog/2022/05/jock-gets-a-good-grounding/. But is there such a thing as too much signal to noise? Not in my not-so-humble opinion, so the quest for improvement continues.

During a phone call with Thomas (Maximum Leader of SWLing.com), I mentioned my curiosity about the 1020C. Thomas said, “MFJ is a sponsor of SWLing.com, I’ll see if they would like to send you one for testing.” Two days later, a package arrived with the 1020C, a power supply for it, and a short coax jumper.

The Basic Layout

The 1020C is small — 2.5” H x 6.4” W x 3.3” D – and looks well made. It covers 300 KHz to 40 MHz. On the front panel are two knobs, a push button, and a selector switch. The left-most knob controls the gain of the amplifier. Moving to the right, you’ll find a push button that controls the bypass circuit.

To the right of the bypass button, you’ll find the band switch, which controls which frequency range is in use, and to the right of that is the tuning knob which allows you to peak the signal in the frequency range you have selected. We’ll get to how it all works in just a bit.

On the back of the 1020C, you’ll find a coax connector labeled INPUT and another labeled OUTPUT, a grounding post, and a connector for the external power supply.

Setup is easy. Plug the power supply into the wall and into the back of the 1020C. (You can also run the 1020C off a 9-volt battery, which we will discuss in a while.) Connect a coax jumper from the OUTPUT connector on the 1020C to the coax input on your receiver. (If you don’t have a coax connector on your receiver, we’ll deal with that issue shortly).

Finally, you need to make a choice about which antenna you want to use. The 1020C Owner’s Manual says:

You may connect either the telescoping antenna provided or an external wire antenna of your choice. To connect the telescoping antenna; screw the antenna end through the top cover and into the spacer located on the PC board. If you chose to use external wire antenna; plug it into the INPUT SO239 connector located on the back of the unit. (DO NOT HAVE BOTH ANTENNAS CONNECTED AT THE SAME TIME!)

Attaching the telescoping antenna can take a while since you may have to hunt around to get the antenna centered on top of the screw inside the 1020C’s case.

Operating the MFJ 1020C

Here’s how I operate the 1020C:

  1. With the BYPASS turned ON (the button pressed in), tune the receiver to the frequency you want to hear.
  2. Set the GAIN knob to around 3 or 4.
  3. Set the BAND knob to the band with the MHz that you are tuned to. You will notice that the red PWR indicator on the 1020C lights up.
  4. Press and release the BYPASS button. This turns on the active preselector and amplification circuits.
  5. Slowly turn the TUNE knob back & forth. At some point in its tuning range, you will hear the signal peak. With the 1020C, I often find there is a spot where the noise peaks and a hair to the side of the noise peak is the sweet spot for listening.
  6. Finally, adjust the GAIN knob for maximum intelligibility of the signal.

Note: When the BYPASS button is pushed IN (the ON position), that means you are hearing the signal straight through from the antenna without going through the amplification and preselection circuits of the 1020C . . . it’s like the 1020C isn’t even there. This is true even if the red PWR LED is illuminated. To put the 1020C to work for you, the BYPASS button must be OUT, and a band must be selected.

The Results of My Tests

Bottom line: the 1020C can really help in certain situations.

Initially, I set up the 1020C with its diminutive 20 inch antenna and connected a coax jumper cable between its coax output and the coax input on the back of the Satellit 800. I wanted to see if it would out-perform the four-foot-long telescopic antenna on the Satellit. No way, I thought; the Satellit antenna is twice as long. But I was wrong. On the first day I tested the 1020C, the atmospheric noise was terrible. I could not hear time station CHU on 3.330 MHz at all with the Satellit’s built-in antenna. But with the 1020C properly tuned, I could hear the time “pips” on CHU clearly.

A couple of days later, when SWLing.com announced the Annual Armed Forces Day Crossband Test —  https://swling.com/blog/2022/05/today-14-may-2022-annual-armed-forces-day-crossband-test/ — I set out to see if I could hear some of the stations. I removed the telescopic antenna from the 1020C and connected the 1020C to my indoor end-fed antenna. Putting the unit in bypass mode, I then started punching in the crossband test frequencies on the Satellit 800. At each frequency, I would first listen to the frequency in “barefoot” mode, then activate the 1020C to see if I could bring any intelligible signal up out of the noise. I had no success until I got to 14.487 MHz USB.  With the straight-through indoor end-fed antenna, I heard nothing, but with the 1020C engaged and carefully tuned, I could copy a station sending in CW: CQ CQ CQ. Later I was able to confirm the ID as NSS from Annapolis, Maryland, one of the stations in the crossband test.

On some easier-to-hear signals, the 1020C sounds as if it lowers the noise floor, improving the “listenability,” but the 1020C does not improve all signals. Sometimes the signal processed by the 1020C sounds roughly the same as the bypassed signal. And sometimes the bypassed signal (straight through from the antenna without the 1020C in-line) simply sounds better.

The pigtail.

Testing the 1020C with a Portable

Next, I tried the 1020C with my Tecsun PL-880. Immediately, I was confronted with a problem: how to get the signal from the coax output of the 1020C and into the antenna socket of the 880. Fortunately, a ham friend fabricated a “pigtail” for me that made the connection from the coax connector on the 1020C to the antenna input socket on the PL-880. As soon as I hooked it up, I heard an unpleasant hum that I had not heard on the Satellit 800.

I decided to see if running the 1020C off battery would offer an improvement. This involved another challenge: there is no “hatch” on the 1020C to provide access for plugging-in the 9-volt battery. Instead, you have to take out the screws on either side of the cabinet, remove the cabinet top, find the 9-volt connector hidden in a little plastic sleeve inside the 1020C, plug in the 9 volt battery, slide it into its clip, replace the cabinet top, and run the screws back in. That, in itself, is not difficult to do, but as soon as the battery needs replacing, you have to go through most of the process all over again.

The good news is that once the 1020C was running off battery, I could detect no hum, and the experience with the 1020C with the PL-880 was much the same as with the Satellit 800. Some signals were improved, some were the same, and sometimes the straight-through (bypassed) signal was better.

I have not tested the 1020C with a large, signal-devouring antenna out in the fresh air. The 2009 edition of Passport to World Band Radio offered that, with an inverted-L antenna longer than, say, 50-75 feet, the 1020C may not provide much benefit. However, my experience with a modest 50-foot indoor end-fed antenna demonstrates that the 1020C can deliver a significant signal boost in some circumstances, and I am glad to have it in my shack.

Bearing in mind that it won’t improve every signal you want to hear, if you live in an antenna-challenged situation, the MFJ 1020C – particularly if you can get 20-50 feet of wire outdoors or run around the perimeter of a room – may be just what the doctor ordered.

Suggestions for MFJ

There are three areas in which MFJ could make life easier for 1020C users: (1) make a pigtail or other device available to get the signal from any wire antenna to the coax input of the 1020C, (2) make a pigtail or other solution to bring a signal from the output of the 1020C to a shortwave portable (possibly a pigtail with an alligator clip to connect to the whip antenna), and (3) offer or provide quick-release pins for the 1020C cabinet for those who wish to operate it off batteries and want to be able to replace them quickly and easily.

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