(Source: Southgate ARC)
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-kaartVERON in Google English
http://tinyurl.com/NetherlandsVERON
LED lights are in widespread use and can cause many problems, ranging from RFI to driving with bright lights from oncoming traffic. Many governments are mandating their use because of the savings in power consumption and longevity. Improper use and bad installation can and does cause problems.
Most of these LED light source emit light in the ultraviolet spectrum and this is where our eyes are most sensitive. As most of you know just before dawn and right after Sun set the light is mostly in the bluish range and this time makes it hard to see as the ultraviolet light is still blinding and making it hard to see. This happens with many LED lights used as street lighting and even worse are the new LED automotive headlamps. Seems there is no way to shield your eyes from this!
RFI is a big problem for our receivers as poorly filtered circuitry of the power supply built in to the LED base can and does make RFI. This can sound like hash or make a interval RFI spike that can cover many or whole bands. I can see these patterns on my SDR waterfall display on my Icom IC-7300 and the same on my TV dongle SDR. Not all make this problem though, I have very inexpensive LEDs from Dollar General (about a dollar each) and they work well as far as RFI emissions. I have some very expensive LED bulbs that were sent to me free from my power company. These ‘free’ ones are very pricey around 35 dollars each at the time, six years ago. They make a hash noise all over the HF spectrum into the VHF and UHF range.
Now were should talk about the RFI from these new computer controlled washing machines!
73 Rod
I wish that the FCC would put more resources towards eliminating RFI rather than wasting them on tracking down Pirates.
Many of us have experienced LED pollution of the SW bands, especially during the Christmas season.
Congratulations to the good people at the Netherlands Radiocommunications Agency.
The amazing thing about this case is that someone knew enough to realize that there was a stray signal on the AIS frequencies and that it was possible to track down that stray signal. Most of the time, people shrug and go on with whatever they were doing.
They indeed do a good job. I once had terrible qrm on medium wave/ long wave caused by a computer power supply. This was so bad, it could be picked up more than 500 meters away from it. They came and I roughly pointed from where the qrm originated. At first, they gave the owner a warning to correct the problem, a good thing because the owner wasn’t aware his computer was causing qrm. But after a brief period the qrm came back. According to what he said the power supply was replaced by another, fresh from the box one. Exactly the same product and causing exactly the same problems. I tried to help him by grounding the computer properly but nothing really made the qrm go away. The power unit was a 500 Watt one, so quite a big one for that time. Ofcourse, made in China and ordered directly from mainland China. No product approval markings such as UL or KEMA were present on the product at all. That told me something. But, to be honest, many products that do bear those markings cause qrm nonetheless. Be it not to the extend that power supply caused that is. He then stopped using that computer. I live in a densely populated area. So qrm is all around me and it spoils my pleasure. It is nearly always computer related but even small phone chargers can cause qrm. As I drive around town, whole areas are polluted with qrm to an extend that radio reception is completely impossible, even local stations disappear completely under a blanket of noises. A problem that seems to be impossible to solve.