There is a very serious problem with the local noise source from low voltage lighting systems. These are sold as pendants, single lights, or multiple lights on a support, such as a bar. The retailer supplies them with a choice of two types of transformers, either a regular magnetic type (non interfering), or an "electronic" supply, which is a very noisy switching supply. The latter is most popular because it's small enough to be contained within the smallest fixture.
I have two neighbors _a block away_ who have incorporated these into a remodel project. These are kitchen overhead lights that create paralyzing noise, particularly on 40m. I sent the manufacturer/model number (Kovacs) to W1RFI, who plans testing to measure radiation intensity. Retrofit for such lighting is very expensive, mostly because of the mechanical changes involved. One of those neighbors was also causing me a problem with his cheap Chinese laptop supply, which I replaced. On the ARRL website there is a list of letters sent to consumers by FCC indicating a need to correct the noise generated by certain devices; several are listed for lighting systems, which undoubtedly are about the switching power supplies in low voltage systems. FCC Part 15, Sections 15.5 and 18.111 prohibit such interference to a licensed radio station. If you know a neighbor who plans a remodel or someone who is building a house nearby, suggest they select the magnetic transformer. These lights are almost always a part of every remodel project. This is a noise source that could seriously affect our hobby when new construction begins en masse again. 73, Jim W6YA ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
