Belkin F5D4076 Noise Test
I did some limited testing on the Belkin Gigabit units. Model F5D4076-S v2.
I only did some quick tests but from what I found, it was not good below 30 MHz.
I did not find any noise at all above 30 MHz so for the scanner listener, I think these should not be much of a concern. See below however for performance issues that make these things not really worth the cost even if they do not cause you interference.
Below 30 MHz, they were very bad and caused great noise.
I had a full scale S9+60dB meter reading on an Icom R9000 receiver between 10 and 20 MHz and just slightly less between 20 and 30 MHz. I had the same results with an AOR AR8200 portable although it only has an LCD bar graph type meter but that meter indicated full signal across the entire HF band. This was both with and without any active data transfers. I unplugged one unit and the noise dropped for a split second and then returned. I unplugged the other unit and noise was gone and radio reception restored.
The noise does get much noisier when actually transferring data but even without a data transfer, the noise is very noisy and not even close to something like a full quieting carrier so you cannot hear any signals at all.
Using a handheld portable on batteries with a whip antenna and an Icom R9000 plugged into the AC mains with an external long wire antenna made zero difference. My longwire is located a distance away and is coax fed reduce or eliminate the chance of my own equipment radiating noise back into my receivers. When I installed the long wire, I tested different locations and placing the antenna as far as possible from my own equipment did make a big difference plus feeding it with coax to a balun also helped greatly in reducing interference from my own equipment. That does not seem to matter with powerline ethernet devices. The noise emitted by these Belkin units wiped out the HF spectrum. They do appear to stop just above the AM broadcast band or around 2 MHz so they at least do not interfere there.
But unlike in the video, this model keeps emitting a very powerful has noise even when not in use. I tried looking them up with an FCC ID number search but found nothing. Oddly, the units themselves have no FCCID printed on them. Maybe it is stamped inside but I will not open them as they will be going back as soon as I'm done testing.
They also do not work very well as I expected due to the use of surge suppressors. I tried to hook them up on circuits without surge suppressors but I think every branch circuit I have has a surge device somewhere along the path. I can't imagine them working well in most homes as many residential or consumer electronics devices now have surge suppression built in from the manufacturer. Plus many consumers are sold on external surge strips and what not when they go out and buy the newest HDTV's and home entertainment setups thanks to salespeople in the big box stores and radio shacks across the country.
I was going to run them and tune around with a spectrum analyzer but I think I've already convinced myself that they are junk and should be forbidden so no further testing is needed in my eyes. There is no way you could listen to HF or SW with these devices in use. It would be impossible as they blanket any signal. Right now, WWV on 5.0 MHz is arriving here with a full scale S9+60 signal but if I fire up one of these Belkin units, I can only hear noise and no WWV at all. Pretty sad if you ask me.
If the link LED on them turns blue then you are linked above 200 Mbps Belkin claims.
I had a hard time getting a blue LED due to surge suppression devices I'd guess. I did manage to find some outlets that offered a rate above 200 Mbps (had blue link LED's) but I still could not find any noise above 30 MHz so that is about the only good thing about them. I did not try and walk any distance from my home to see how far they would radiate but my guess is far enough and that if a neighbor had them in a typical suburban residential home setting that I'd be affected for HF monitoring several homes distance away.
I do plan on testing them at work were we have no residential nor do we have a need for HF or SW radio monitoring. So they should not be an interference concern there and my testing will only be for performance to an outside building about 300 feet away. Currently I'm using two pairs of a company owned 200 pair phone cable as an ethernet connection. I can only get a reliable ethernet connection of 10 Mbps on that setup. Any higher speeds and I start seeing a lot of retransmits and collisions or errors.
I'm curious if these powerline devices will transfer along the underground power lines to that building with a higher rate or any rate for that matter above 10 Mbps. I wonder if the power cables being underground will just attenuate the signal. I'm fortunate for this test as I can tap the power just before it goes underground and right were it reappears at the other end.
I will still not use them even if they do work and this is only a performance test. Wireless is not an option for this building in case anyone is wondering. I'll use dsl campus modems should I need a link higher then 10 Mbps.
So in a nutshell, I do NOT recommend these types of powerline ethernet devices especially if you care about and/or enjoy monitoring our valuable radio spectrum or have a neighbor that is into monitoring or is an amateur operator. They should simply be banned but I guess the FCC is only interested in revenue and could care less about polluting our radio spectrum.