The Coast Guard warns that LED lighting may interfere with VHF radio and AIS reception. The Coast Guard says it has received reports from crews and others about poor reception on VHF frequencies, DSC (digital selective calling), and AIS (automatic identification systems) when they are used near LED night-time lighting, nav lights, searchlights and floodlights on boats.
The interference can create potential safety hazards. In one port, a rescue coordination center was not able to contact a ship in a traffic separation incident by VHF radio; that ship also reported poor AIS reception. The Coast Guard says that ships in different ports have reported interference in their VHF and AIS systems caused by LED nav lights. LED lighting installed near VHF antennas can make the interference worse.
The Coast Guard says you can test for possible LED interference by doing the following:
- Turn off LED lights.
- Tune the VHF to a quiet channel – CH 13.
- Adjust the squelch control until you hear noise.
- Re-adjust the squelch control until the noise is quiet.
- Turn on LED lights.
If the radio now outputs noise, the LED lights have raised the noise floor, and it is likely that the LED lights are degrading the VHF and AIS reception. Read more: