LED radio inteferance

[Tony Brooks]

I have just come across this document and in the light of several threads though it might be useful -especially to vendors who can look at the EU standard they are supposed to observe.

 

http://www.ukqrm.org.uk/lighting.php

[Sea Dog]

Interesting site Tony, and for more than just this single issue. Thanks. for posting.

 

I wish I'd found it about a couple of years ago when next door was knocked down and a Grand Designs steel framed job went up. Once the steel cage was complete, my mobile phone signal went from 4 bars to none. I tried Ofcom, the local authority, etc, but they weren't much help and I may as well have been speaking Greek when I raised parasytic arrays and RF re-radiation. I've moved suppliers to 3 and have a box which gets me a good signal through my internet connection now so I'm over it (grrr, well nearly!) but this looks like a good site for such issues too.

[FORTUNATA]

As I posted in another section, my boat is filled with radios. As it happens, some of them can get no signal due to the steel structure of the boat but they work fine on the GRP. One radio I have by my bed is a Transwave from 1965. I can't get anything if my halogen ceiling lights are on. Switched off and placed by the window, I can pick up stations.

The big tube radios can pick up everything - more amplification and bigger aerials.

Either they were built with ferrite rods or, in some cases, frame aerials.

For boats, the true marine radio is the Zenith. These were designed for yachts and date back to the fifties era. I don't own one but maybe one day.

[Colin North]

I can vouch for issues with RF (Radio Frequency) noisy LEDs as used for cabin lighting.

I have purchased LEDS from two of our Canal Based LED suppliers and from other cheaper sources.

The LEDs purchased form the Canal Based LED suppliers were of the more expensive kind, fully regulated with the voltage specification of 10-30V These are totally RF silent at all frequencies that I have measured (1MHz - 430MHz) and I have not had any problems.

I decided for follow the collected wisdom of a few on this site and purchase some cheapies from other sources. What a difference. The three samples I have are definitely RF noisy to the point the FM radio is unlistenable and Amateur Radio is not viable. I now use these LEDs as lead lamps for working on the engine etc., as their RF Interference does not bother me then.

Yes, I know there are (probably) many good cheap LEDs out there but I cannot be bothered to keep buying them until I find a quiet one.

 

Colin G4GBP

[Keeping Up]

I find it intriguing that the article recommends using resistors as voltage droppers for LEDs instead of solid state circuits. Yes it will eliminate interference, but it will also make the LEDs almost as inefficient as a conventional bulb.