Monthly Archives: March 2021

Dan spots a rare Collins 51S1 LTV G133 F military receiver on eBay

Many thanks to SWLing Post contributor, Dan Robinson, who notes:

This military version of the 51S-1 receiver is almost never seen on the used market.

Click here to view on eBay.

Thank you, Dan! The seller claims that this radio is fully working with tubes replaced and has undergone a complete alignment. Hopefully, caps have been replaced as well.

I’ll admit: if I had the space, I would add this rig to my collection in a heartbeat, although I expect the price of this unit will far exceed my budget!  It is a beauty, though.

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HF-START Web Tool: A new web-based, real-time shortwave radio propagation application

Many thanks to SWLing Post contributor, Tracy Wood, who shares the following journal abstract from EurekaAlert.com:

Commencement of shortwave propagation simulator (HF-START) service

Demonstrating radio wave propagation paths between any two points based on real-time space weather information

NATIONAL INSTITUTE OF INFORMATION AND COMMUNICATIONS TECHNOLOGY (NICT)

[Abstract]

The National Institute of Information and Communications Technology (NICT, President: TOKUDA Hideyuki, Ph.D.), in collaboration with Electronic Navigation Research Institute, National Institute of Maritime, Port and Aviation Technology (ENRI, Director General: FUKUDA Yutaka) and Chiba University (President: TOKUHISA Takeshi), has started the service of shortwave propagation simulator (HF-START). It provides real-time shortwave propagation that reflects real space weather information from ground-based observations and model calculations. The HF-START web system has been successfully developed and is now available at https://hfstart.nict.go.jp/.

The web calculation function of this system allows shortwave propagation between any two points in Japan based on real-time GNSS observations and between any two points on the Earth based on model-based space weather information. Real-time estimation is possible. The calculation in the past and up to about 1 day ahead in the future is also possible. In addition to amateur radio, HF-START is expected to benefit efficient frequency operation of aviation communications that relies on shortwave in the polar route.

[Background]

Communication and positioning technologies play an important role in social infrastructure in various fields today. The ionosphere has regular temporal cycles and fluctuates greatly every day associated with solar activity and space environment. Of benefit to us is the fact that ionosphere is good at refracting shortwave, which is why we can hop shortwave signals off the ionosphere to communicate with people over large distances.

Shortwave band has been used for communication and broadcasting for a long time, and are still widely used in radio broadcasting, aviation communication, amateur radio, etc. Ionospheric variation, however, has a great influence on the propagation of radio waves. Communication environment such as the communication range and usable frequency changes significantly due to the influence of the ionospheric fluctuation. Thus, fluctuations in the ionosphere affect the operation of shortwave broadcasting, aviation communications, and amateur radio.

There have been websites that provide estimated information on how radio wave propagation changes due to such ionospheric fluctuations. The problem is that it is based on a simple model and does not reflect realistic ionospheric fluctuations.

[Achievements]

We have developed a shortwave propagation simulator HF-START that estimates and provides shortwave propagation information in real-time under realistic ionospheric fluctuations based on ground-based observations and model calculations. We open real-time information estimated by HF-START, and the web application at https://hfstart.nict.go.jp/.

Figure 1 shows an example of visualization of shortwave propagation by HF-START. In this system, the user can check the radio wave propagation information that is updated in real-time. As shown in Figure 2, the user can also use the web application to estimate and visualize radio wave propagation by specifying any frequency in the range of 3-30 MHz, any two points on the Earth, and any transmission angle. The date and time can be set retroactively to the past (after 2016), to the real-time, and in the future (up to about 1 day ahead).

The system can be used to visualize the radio propagation path and clarify whether it is affected by space weather when the shortwave you are using does not reach the destination, or when you can listen shortwave broadcasted from the far source that normally you cannot hear. Furthermore, in addition to amateur radio, it is expected to benefit efficient frequency operation of the aircrafts that use shortwave in polar route.

[Future Prospects]

We are conducting research and development to extend the HF-START to estimate radio wave propagation not only in the shortwave band but also in other frequency bands. In addition, we will evaluate the simulator accuracy and improve it by comparing it with radio wave propagation observations.

NICT has been providing information related to communications, satellite positioning, and radiation exposure since November 2019 as a member of the Global Space Weather Center of the International Civil Aviation Organization (ICAO). With the HF-START service, we expect to improve the information provided to directly relate to communications, such as communication range information.

###

As the abstract mentions, you can use the tool online now via the HF-Start Web Tool.

Thanks so much for the tip, Tracy. This is fascinating!

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Jack finds that chokes have a huge impact on switching power supply noise

These “Wall Wart” type adapters can create a lot of RFI

Many thanks to SWLing Post contributor, Jack Dully, who writes:

I was putting some things in my radio junk parts box and came across some chokes. So I tried a test with my Tecsun PL-880 on battery and the Tecsun supplied switching AC adapter, with and without chokes on the adapter.

WOW!

I tuned to a vacant station on battery power with headphones on. Then on AC power, the hash and static were incredible. Putting one large choke on the adapter power cord, wrapped about four times and it decreased considerably. So I attached a second choke and once again the static & hash decreased even more, almost to the point of sounding like I was running just on battery power.

Those chokes really do work well.

Thank you for sharing this, Jack. I almost never operate my portables while connected to a power supply, so I often forget about the importance of using a choke with inexpensive, lightweight radio power supplies. Thing is, so many things in our houses and shacks are powered by these QRM generators. In the shack, I’ve added chokes I’ve picked up at hamfests to a number of various power supplies. It does certainly help decrease the noise level. I’ve even used them on power cords for other appliances in the house that tend to spew RFI.

If you ever find a deal on chokes at a hamfest or electronics store, grab some. They can be an affordable solution for those noisy power supplies we still rely on.

Thank you for the reminder and  tip, Jack!

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Tecsun PL-330 tip: Using the telescopic antenna for the LW & MW bands

Many thanks to SWLing Post contributor, Mad Radio DXer, who writes:

Hi,

I want to let you & your readers know of a Tecsun PL-330 trick that I saw mentioned in the comments section of your blog some time ago which does not seem to have a lot of awareness. This is for using the telescopic antenna for the LW & MW bands, & it works for the 3305 version of the PL-330 which I understand is the export version. The original comment I saw said this also works for the Chinese version of the PL-330, before firmware 3305.
It is very easy to do & instructions are the following…

1. Turn on the radio.
2. Select either the MW or LW band.
3. Press the number 3 key down for a few seconds, until the display shows “CH-S”.
This means the MW & LW bands can now be received with the telescopic antenna.
4. To use the ferrite bar again, press the number 3 key until “CH-A” appears on screen.

I also did a YouTube video showing this trick in action…

This reminds me of the trick used for the Degen DE1103 PLL version which allows reception of the telescopic antenna for the MW band. However, in my opinion this is much easier to use on the PL-330 than the DE1103 PLL which could be very fiddly. Also this trick is most effective on the LW band, as I find Chinese portables are usually very weak on this part of the band which is good news for LW DXers. I hope you & everyone reading find this trick very useful & that it works.

Thank you so much for the excellent tip!

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Radio Waves: Friedrichshafen Cancelled, Coast Guard Seeks Rare Diode, Kindred Spirits in DXing, and DRM Pitch for India’s FM Band

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 Dennis Dura, Ron Chester, and Mangosman for the following tips:


Ham Radio Verbindung 2021 kommt nicht zustande/Ham Radio convention 2021 has been cancelled (Messe Friedrichshafen)

[Note that the following is a Google translation of the original piece in German]

Ham Radio cannot take place this year either – other trade fair events remain on course

Due to the current corona developments, Messe Friedrichshafen cannot hold the international amateur radio exhibition Ham Radio in the planned period from June 25 to 27, 2021. Instead, the industry meeting will take place from June 24 to 26, 2022.

“The decision was not an easy one for us, but a trade fair like Ham Radio lives from its high level of internationality. Due to the current uncertainties in the travel sector, implementation is currently not feasible, ”explains Klaus Wellmann, Managing Director of Messe Friedrichshafen. All other trade fair events in the second quarter of 2021 and beyond should take place as planned at the present time. “A large percentage of our customers from these industries are still on board at the 2021 events. Together we hope that the immunization of society continues to gain momentum and that we can carry out the events with appropriate protection and hygiene concepts. “

Further information at: www.messe-friedrichshafen.de and http://www.hamradio-friedrichshafen.de/.

Rare Diode Threatens Coast Guard’s Arctic Ambitions (Hackaday)

The United States Coast Guard heavy icebreaker Polar Star is literally a one-of-a-kind ship. After its sister Polar Sea was deactivated in 2010 it became the most powerful icebreaker in the fleet, and one of only two US icebreakers capable of operating in the treacherous polar regions. The vessel is critical to protecting America’s scientific and economic interests in the Arctic, but according to a recent article in Business Insider, the ship’s age and scarcity of spare parts is making an already difficult mission even harder.

In the article, Captain William Woityra specifically mentions that the ship’s diesel-electric propulsion system is running on borrowed time as the diodes used in its AC/DC rectifier are no longer manufactured. With none remaining in the Coast Guard’s inventory, the crew has had to turn to eBay to source as many spares as possible. But once their hoard runs out, Captain Woityra fears his ship will be dead in the water[]

A toast to the fools standing high on broadcasting’s hill (Doc Searls Weblog)

In Winter, the cap of dark on half the Earth is cocked to the north. So, as the planet spins, places farther north get more night in the winter. In McGrath, Alaska, at close to sixty-three degrees north, most of the day is dark. This would be discouraging to most people, but to Paul B. Walker it’s a blessing. Because Paul is a DXer.

In the radio world, DX stands for for distance, and DXing is listening to distant radio stations. Thanks to that darkness, Paul listens to AM stations of all sizes, from Turkey to Tennessee, Thailand to Norway. And last night, New Zealand. Specifically, NewsTalk ZB‘s main AM signal at 1035 on the AM (what used to be the) dial. According to distancecalculator.net, the signal traveled 11886.34 km, or 7385.83 miles, across the face of the earth. In fact it flew much farther, since the signal needed to bounce up and down off the E layer of the ionosphere and the surface of the ocean multiple times between Wellington and McGrath. While that distance is no big deal on shortwave (which bounces off a higher layer) and no deal at all on the Internet (where we are all zero distance apart), for a DXer that’s like hauling in a fish the size of a boat.

In this sense alone, Paul and I are kindred souls. As a boy and a young man, I was a devout DXer too. I logged thousands of AM and FM stations, from my homes in New Jersey and North Carolina. (Here is a collection of QSL cards I got from stations to which I reported reception, in 1963, when I was a sophomore in high school.) More importantly, learning about all these distant stations sparked my interest in geography, electronics, geology, weather, astronomy, history and other adjacent fields. By the time I was a teen, I could draw all the states of the country, freehand, and name their capitals too. And that was on top of knowing on sight the likely purpose of every broadcast tower and antenna I saw.[]

DRM Makes Its Pitch for India’s FM Band (Radio World)

In India, where regulators have been working toward recommending a standard to digitize the FM band, Digital Radio Mondiale is presenting its case.

DRM has been conducting trials and demos since late February, when a digital radio transmission with three audio services and Journaline text information went live in Delhi alongside existing analog FM transmissions.

It said it is also showing the possibility of extending a shared transmitter infrastructure by broadcasting up to six individual DRM signals or blocks, carrying up to 18 audio services plus 6 multimedia services, being broadcast from one FM transmitter and antenna. It said the number of individual DRM signals is only limited by the bandwidth of the transmitter. Each signal can have its own power level, and gaps in the spectrum are possible, as are individual SFN networks per DRM signal.

“The transmission is part of an extensive trial and demonstration of DRM conducted by Prasar Bharati and its radio arm, All India Radio (AIR), with the help of the DRM Consortium and its local and international members,” DRM stated in a press release. “The test was officially launched on Feb. 24 and 25 at the headquarters of All India Radio in New Delhi.”

The test was requested by regulator TRAI and the Ministry of Information & Broadcasting.

DRM officials said a presentation to AIR’s committee showed DRM in the FM band on various car radios including line-fit, aftermarket, standalone receivers, mobile phones and tablets. A head unit from Mobis, upgraded for FM via firmware, was installed in a Hyundai Verna. DRM said, “The reception was found to be excellent for over 15 km radius with just 100 W of DRM power in digital,” including 5.1 surround sound test broadcasts on DRM.[]

You might also check out the article HD Radio and Digital FM in India at Radio World.


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RNEI seeks your feedback on test transmission this weekend

RNEI Test Transmission to the whole of Europe on Sunday the 28th of March, 17:30UTC. 7420kHz

We’re having a test transmission from Armenia this Sunday, the 28th of March 2021. on 7420KHz.

You’ll hear RNEI 15 but different songs will use different processing so we’d love it if you told us which songs sounded the best sound quality and which sounded the worst sound quality on your equipment!

This transmission will be with 100kW being fed into a 330 degrees beam that delivers signal to the following:

Strong Signal:

  • Ireland
  • UK
  • Nordic Countries (Finland, Norway, Sweden, Faroe Isands, Iceland & Denmark)
  • Baltic Countries (Latvia, Lithuania, Estonia)
  • Belgium, Netherlands, Luxembourg
  • Poland
  • North and West Germany
  • Northern Switzerland
  • Central and Northern France
  • Belarus
  • Romania
  • Bulgaria
  • Moldova
  • Ukraine
  • Hungary
  • Slovakia
  • North Macedonia
  • East Bosnia
  • Serbia
  • East Czechia

Good Signal:

  • Greece
  • Albania
  • West Bosnia
  • Slovenia
  • Austria
  • Southern Switzerland
  • Northern Italy
  • West Czechia
  • Croatia
  • Montenegro
  • Spain
  • Portugal

We look forward to reading your reception reports!
Wishing you well
Roseanna

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Back to life…

If you’re written an email inquiry to me, you may have noticed I’m nearly two weeks behind in replies. Not only has family life been very active but earlier this week we believe I got a touch of food poisoning. I’m slowly getting back on my feet and feeling human again, but it has certainly zapped me of energy and I, frankly, haven’t felt good enough to even look at a computer screen until today.

Books and radio listening have been my refuge and distraction.

I’m slowly starting to feel better but just know things might be in low gear here the next few days.

I will be back. And this post will likely self-destruct in two days because…well…I’d like to simply forget this whole incident!

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