Yearly Archives: 2018

LED QRM jams maritime Automatic Identification System

LED lights jam shipping Automatic Identification System

VERON report investigators from the Netherlands Radiocommunications Agency have discovered RF Pollution emitted by LED lights caused the loss of AIS shipping signals around 162 MHz

A Google English translation of the Radiocommunications Agency article reads:

In the mouth of the Waalhaven in the Nieuwe Maas in Rotterdam, ships from the electronic map have been missing for some time. The Port of Rotterdam Authority and skippers were completely in the dark about the cause of this.

In the busy Rotterdam port area, of which the Waalhaven is a part, it is important that you know where everyone is. A ship that automatically sends its position and data via AIS – and is therefore visible on the electronic navigation chart – not only increases safety, but also shortens the waiting times for the berths and waiting areas. And what about ships loading and unloading dangerous goods or passenger ships? These are continuously monitored. If such a ship is dropped, dangerous situations can arise.

During an investigation the inspectors of the Radiocommunications Agency quickly discovered that the frequency band for AIS signals was disturbed. And after several polls in the surroundings of the Waalhaven they came to a work of art. In an atelier near the mouth of the Waalhaven, an artist had made a work of art with the help of LED lights. All these lights appeared to be the key to the solution together with the power supply.

Because LED lights are indeed economical, but if you do not buy the right one or install them incorrectly, they cause a lot of problems. In this case, the frequencies of the AIS band were therefore disturbed. After the power of the lighting was switched off, the disruption was resolved. In retrospect, it appeared that the lighting and the power supply exceeded the interference limits. To prevent new failures, a solution is sought for the artist together with the business community.

The agency also regularly receives reports of disruptions of AIS reception from the Amsterdam port area. Here, too, we conduct an investigation. If something interesting comes out of this, you may read more about this in the next newsletter. To prevent disruptions, we regularly monitor frequency use (preventively). Especially in areas with busy shipping traffic.

Source Netherlands Radiocommunications Agency
https://magazines.
agentschaptelecom.nl/
ontwikkelingenindeether/2018/03/
schepen-verdwenen-van-de-elektronische-kaart

VERON in Google English
http://tinyurl.com/NetherlandsVERON

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Olivier is pleased with the Sony SRF-M95, shares internal photo

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Many thanks to SWLing Post contributor, Olivier Tkaczuk (F4BXV), who writes:

Hello, my name is Olivier TKACZUK 36 years F4BXV and I live in the north of France.

Just to present my last Sony SRF-M95 AM/MW bought on eBay for 13 euros.

[I regularly receive] Absolute Radio in England…and also Radio Nacional de España.

[H]ere is an internal photo:

Thank you for your website it gives me taste on the radio.73’s Olivier F4BXV

Many thanks, Olivier! I’ve always loved this über-compact AM/FM radios. They remind me of the small radios I used to sneak into school when I was a kid! Sounds like the SRF-M95 is a capable little receiver as well–thanks for sharing the photos.

Glad you’re enjoying the SWLing Post!

Click here to search eBay for the Sony SRF-M95.

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“Slow Scan Radio” is a new digital program on Channel 292

My Radio Spectrum Archive HOPE XII presentation on Hackaday

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Wow! Thank you, Hackaday:

HOPE XII: TIME TRAVEL WITH SOFTWARE DEFINED RADIO

by: Tom Nardi

It’s easy to dismiss radio as little more than background noise while we drive. At worst you might even think it’s just another method for advertisers to peddle their wares. But in reality it’s a snapshot of the culture of a particular time and place; a record of what was in the news, what music was popular, what the weather was like, basically what life was like. If it was important enough to be worth the expense and complexity of broadcasting it on the radio, it’s probably worth keeping for future reference.

But radio is fleeting, a 24/7 stream of content that’s never exactly the same twice. Yet while we obsessively document music and video, nobody’s bothering to record radio. You can easily hop online and watch a TV show that originally aired 50 years ago, but good luck finding a recording of what your local radio station was broadcasting last week. All that information, that rich tapestry of life, is gone and there’s nothing we can do about it.

Or can we? At HOPE XII, Thomas Witherspoon gave a talk called “Creating a Radio Time Machine: Software-Defined Radios and Time-Shifted Recordings”, an overview of the work he’s been doing recording and cataloging the broadcast radio spectrum. He demonstrated how anyone can use low cost SDR hardware to record, and later play back, whole chunks of the AM and shortwave bands. Rather than an audio file containing a single radio station, the method he describes allows you to interactively tune in to different stations and explore the airwaves as if it were live.[…]

Continue reading the full article at Hackaday.

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Bill tunes to WWFD in AM HD

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Many thanks to SWLing Post contributor, Bill Mead, who writes:

Thomas, I’m sending you a short clip from WWFD 820 kHz in Frederick, MD. It’s America’s only all-digital station, apparently. They are HD only with a relatively eclectic music format. I’m hearing them at my QTH in Harrisburg, PA, about 80 miles or so north of their transmitter which is 4.3 Kw daytime. I sort of doubt they’ll come in at night when they drop down to 430 watts, but who knows.

My experience with HD on MW is that it can be heard at pretty decent distances under ideal conditions but the slightest bit of interference, a lightning strike or someone switching on the lights for example, and it’ll lose the HD lock.

My HD receiver is a Sony XDR-F1HD. It’s well-known as an excellent FM DX machine. What’s not as well-publicized is that it’s a very decent MW receiver as well. All it needs is a good MW loop antenna directly connected to the AM ANT terminals on the back of the radio.

Click here to view on YouTube.

Excellent! Thanks for sharing, Bill. I’m passing by Frederick, MD in a couple of weeks and plan to tune to WWFD in both my car and with the Sangean HDR-14.

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FTIOM & UBMP, July 29-August 4

Boat Anchor Tuesday: Hallicrafters S-40B and SX-100

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Many thanks to SWLing Post contributor, Chris Peters, who shares the above photo for Boat Anchor Tuesday and writes:

I was lucky enough to recently pick up both these familiar faces for $150.

Hallicrafters S-40B and SX-100

Both are in decent shape but are due for a recap and alignment.

Wow–both of these are classic sets, Chris! After a recap and alignment, I think you’ll especially be impressed with the performance that SX-100 delivers! Thank you for sharing!

Post readers: If you’d like to share a photo of your boat anchor on Boat Anchor Tuesday, simply send me an email with the photo and a short description. I’ll put it in the pipeline to publish!

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