Powerline Ethernet Adapters… DO NOT USE!

June 29th, 2014

Power over Ethernet (PoE) has some good uses if the primary function of the cable installation is for data, such cables may be screened or twisted to eliminate the radiation of interference. The ludicrous thing about ‘powerline adapters’ is the fact that data is superimposed onto mains house wiring not designed for carrying data and not in anyway screened to prevent these interfering frequencies radiating. Data is, in most cases a serial stream of pulses, the faster the data transfer the shorter the pulse duration. A digital pulse stream is a series of ons and offs resulting in a ‘square wave,’ one specific property of a square wave is that the radiation it emits is rich in harmonics, multiples/divisions of the original frequency superimposed onto it, with data the differences in pulse width equate to a wide frequency range being geometric in progression when harmonics are included. The varying pulse width and duration with data transfer produces a broad range of interference frequencies each with a cascade of high amplitude harmonics, this is why electronic digital devices have standards to adhere to, regarding the spurious emission of interference, a major factor in electronic design encompasses the elimination of these.

If you use ‘powerline adapters’ try this: Turn on an ordinary radio and tune to the FM band, initiate some form of data transfer between the adapters, next try and find a station on that radio you just turned on! DAB radio reception is also compromised and any station tuned to will be completely lost. Interference as mentioned is wideband, so the problem is not only with FM broadcast, AM radio (LW, MW & SW) plus any kind of hobby radio, eg: CB, Amateur Radio will be affected, even remote control kits & toys.

So if you are sucked in by the powers that be and are convinced the only option to be able stream Netflix to your nice new shiny Smart HDTV is by these devices, spare a thought for your neighbours and whether their lifestyle might be affected.

Entry Filed under: General