Ethernet + ham radio = crap!!

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The title says it all, Ethernet + ham radio = noise all over many bands, HF to VHF!

I have S6 to S9 of noise from my ethernet which affects 20M and even up to 2M!. I'm still trying to find out if there is a definate source, or if it's all from one or two offenders.

Basically I have fiber optics to my home --> then ethernet to a router/firewall/wireless hub ---> then a line to a 1Mbps switch which has eight ports on it, 1 goes to the router, each of the remaining 7 go to different rooms in my home.

Shutting off the switch kills most of the noise.

Previously I was proud to say I have a hardwired home (great bandwidth, gigabit speeds), no need for wireless except for when using a laptop on the couch or on the back deck.

Now I almost wish I went totally wireless!

So if any of you are starting to play with ham radio and notice that the noise floor is too high (especially on 2 meters), try shutting off your ethernet network and see if the noise floor drops!

I have a bunch of ferrite filters that I've been saving for years, I guess it's time to see if they will solve this without killing the ethernet performance.
 

whatluck

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This is a common problem for buildings with dense ethernet. Cat6 helps to alleviate the problem. I would avoid wireless, as it it very susceptible to interference. Also, try a good old 100Mbit switch. The higher the frequency the equipment clocks at, the more susceptible it is no noise from your 110VAC power source. Cheap gigabit switches have CHEAP power supplies. I find a lot of switching problems are most often caused by 'ditry' input power. Also, your ethernet cable needs to avoid lighting ballasts, compressors, motors, etc, as ethernet cable acts like an antenna and sucks up that 60Hz. You can also try diconnecting 1 cable from the switch at a time. This will tell you if its the switch or one of the runs, and which one. Keep me posted!
 
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I have the same problem. The only solution I came up with is to shut it off when I am operating. I have my network stuff clustered on two strip outlets so if the noise from the ethernet causes RFI on a frequency I am trying to operate on, I just turn off both strip outlets and the whole ethernet goes away. BTW, I tried the ferrites and the cat6 cables but it did not help.
 

whatluck

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I have the same problem. The only solution I came up with is to shut it off when I am operating. I have my network stuff clustered on two strip outlets so if the noise from the ethernet causes RFI on a frequency I am trying to operate on, I just turn off both strip outlets and the whole ethernet goes away. BTW, I tried the ferrites and the cat6 cables but it did not help.

Did you leave the switch on and unplug all of your cables one at a time? Do you have the noise with just the switch plugged in? Is your switch on the same circuit as your radio equipment?
 
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There are numerous sources, The switching wall warts generate some and the switches / routers generate some. I went through it a while back and they all make a contribution. I have two "clusters" of ethernet equipment. The simplest solution (for me) is to just shut it alll down while I am on the air.
 
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Simple solution to this has been around for years.

Shielded Twisted Pair

(correction) Unfortunately most ethernet is just TP, not STP.

My noise goes away when I power down the switch. I haven't isolated it to one or two (or more) connections yet as it's a long walk from the radio, to the switch and back. One of these days a friend will stop by with his HT and we'll debug this a bit more.

In my case the switch and router are in a closet in the center of the house. All ethernet lines come to this point.

My shack is in the basement.

For now, I put an X-10 switch on the input to the powersupply to the 1Gb switch. So I can turn off the power to the network switch from my shack and allow my shack computer (a laptop for now) to get to the internet via wireless router.

I won't go all wireless, that's a different type of mistake!
 
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Ferrite toroid s are your friend. It is a long process to find and debug them all. I have dimmers in my house for lights but I seem to have limited all the other noise sources. Now if I could just get that pesky amp to stop oscillating.
 
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I forgot to follow up on this thread.

I found out that I had a strange issue that was the cause of this noise!

It turned out that the issue was caused by the RJ45 plug block that I was using. They were all in a line and the ends of the wires going through the punch block of one RJ45 ended up touching the wires of the block next to it!!!! [angry]

When I found this, I ended up trimming the end of the wires as short as I could, then I also added some mylar tape over the ends of the wires at each block, to ensure that this wouldn't happen again.

My noise level on HF went down significantly! I can actually operate HF again without shutting down my house hardwired ethernet.

Wow was I happy! [smile]
 
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