LED Lighting interference on VHF Frequencies

[tartansailor]

Has anyone experienced this interference on their boats?

LED Lighting interference on VHF Frequencies
SAFETY ALERT - LED LIGHTING INTERFERENCE VHF FREQUENCIES

United States Coast Guard
Inspections and Compliance Directorate
Washington, DC

August 15, 2018

Safety Alert 13-18

Let us enlighten you about LED lighting!
Potential interference of VHF-FM Radio and AIS Reception.

The U.S. Coast Guard has received reports from crews, ship owners, inspectors and other mariners regarding poor reception on VHF frequencies used for radiotelephone, digital selective calling (DSC) and automatic identification systems (AIS) when in the vicinity of light emitting diode (LED) lighting on-board ships (e.g., navigation lights, searchlights and floodlights, interior and exterior lights, adornment).

Radio frequency interference caused by these LED lamps were found to create potential safety hazards. For example, the maritime rescue coordination center in one port was unable to contact a ship involved in a traffic separation scheme incident by VHF radio. That ship also experienced very poor AIS reception. Other ships in different ports have experienced degradation of the VHF receivers, including AIS, caused by their LED navigation lights. LED lighting installed near VHF antennas has also shown to compound the reception.
Strong radio interference from LED sources may not be immediately evident to maritime radio users. Nonetheless, it may be possible to test for the presence of LED interference by using the following procedures:

1. Turn off LED light(s).
2. Tune the VHF radio to a quiet channel (e.g. Ch. 13).
3. Adjust the VHF radio's squelch control until the radio outputs audio noise.
4. Re-adjust the VHF radio's squelch control until the audio noise is quiet, only slightly above the noise threshold.
5. Turn on the LED light(s).
* If the radio now outputs audio noise, then the LED lights have raised the noise floor. (Noise floor is generally the amount of interfering signals / static received beyond the specific signal or channel being monitored.)
6. If the radio does not output audio noise, then the LED lights have not raised the noise floor.

If the noise floor is found to have been raised, then it is likely that both shipboard VHF marine radio and AIS reception are being degraded by LED lighting.
In order to determine the full impact of this interference, the Coast Guard requests those experiencing this problem to report their experiences to Coast Guard Navigation Center . Select "Maritime Telecommunications" on the subject drop down list, then briefly describe the make and model of LED lighting and radios effected, distance from lighting to antennas and radios effected, and any other information that may help understand the scope of the problem.

This Safety Alert is provided for informational purposes only and does not relieve any domestic or international safety, operational, or material requirement. Developed by the U.S. Coast Guard, Spectrum Management and Telecommunications Policy Division. Distributed by the Office of Investigations and Analysis. Questions may be sent to HQS-PF-fldr-CGF-INV@uscg.mil.

[hilbert]

I've had no interference with Marine Grade LED Lights from MarineBeam, https://store.marinebeam.com/.
See their article on EMI at: https://store.marinebeam.com/controlling-emi-1/

I started purchasing from MarineBeam after reading posts from Maine Sail like this one,
https://www.sailnet.com/forums/gear-mai ... lbs-6.html

As Maine Sail says, Jeff at MarineBeam is a pleasure to work with.
When I broke the glass diffuser for a fixture during installation, Jeff sent me out a new one at no charge.

[Steve Laume]

I have lots of LED bulbs on Raven. The first ones I installed in the dome light fixtures were early designs that had a socket connected to a flat panel of LEDs. My VHF is mounted on the head liner just inside the companion way near the stove. One of the dome lights is right next to it and if I turn it on, I do get radio noise. It is more noticeable on the FM radio. These are both tied together with a splitter that is also close to the dome light. When using the reading lights I do not notice any change in reception. I can use the dome lights in the head or even on the opposite side of the galley and not notice a change. I recently changed out those dome light bulbs but have not had a chance to see if the newer bulb designs make any difference.

I also have LED bulbs in my running lights and an LED tri-color on the mast head, right next to the VHF antenna. I have never notice those having any effect on radio reception.

We have changed to LED bulbs at home as well and the light on top of the Fm receiver creates a lot of static. The ones that are 8 or 10 feet away don't seem to have any effect.

Please don't let the CG take my LEDs away, Steve.