Network Interferance

Andrew Billingham

It seems my network switch is interfering with my radio. I have changed all the cables to Cat 6 and still no joy. Anyone else had this problem and if so how did you get around it.

WK2Y

Need to figure out if it's coming in on the cables, directly from the switch, or from the power supply (wall wart?)  for the switch. When you say switch do you mean router or do you have a separate switch?  Does the interference change if you orient the switch differently?  How about the cables?  For cables and wall warts Palomar Engineering has some nice suppression gear.  You can also consider using fiber optic.  That provides a bunch of other advantages. I can provide more details if you want.
73, 
Bob, WK2Y

Steve KD2OM

It is recommended to put a shield breaker in the CAT6 if it is shielded. Get a plastic coupler and use a very short cable, 6 inches or so to the radio.

73,
Steve KD2OM

Andrew Billingham

Hi Bob, I have a separate switch off the router as my shack is upstairs.  I know its coming from there as I'm getting the interference on my Kenwood ts 990 

WK2Y

Do you have a ground strap between the switch and the rig?  Might help.

Andrew Billingham

The only problem I would have is I’m on the second floor.

Steve Blankinship AG4SO

Good morning I have a FLEX 6400 as Bob suggested it helps to isolate the source , if your sure it is the switch then you have two choices first try RFI mitigation with Ferrite chokes. I also suggest Palomar Eng  they have kits for specific radios, I have installed the one for FLEX radios on my 6400 that is installed in a repeater shack 6' from the switch/router. It significantly reduced the noise floor on the water fall. The kit provides chokes for all the cables on the FLEX. if that fails you may need to also add chokes to your switch. Let us know how it turns out. Steve AG4SO  
https://palomar-engineers.com/rfiemi-solutions/Radio-Communication-RFI-Solutions-c21444152
BTW when installing the choke kit ensure other network cables are not paralleling the radio NIC cable and cross coupling. 

WK2Y

2nd floor does present issues but they can be overcome.  See this article by Guru Tim:

https://helpdesk.flexradio.com/hc/en-us/articles/204779159-Grounding-Systems-in-the-Ham-Shack-Paradigms-Facts-and-Fallacies

It's really great.  In particular you may want to consider alternative 2.

Roger Hartel

I have a similar issue with interference every 60Khz across all bands. Ferrite chokes on all of the cables in and out of the switch will help reduce the level. I have heard that a 100 mhz switch might be quieter than a 1gb switch but I can't find one.

Andrew Billingham

Hi Rodger. Yep it’s the same here. I think some filters on the main feed to the switch would help. but I caiswem to find anyy

Roger Hartel

I put ferrites on all cables at the switch and at the destination. I live in a 2 story home with a basement, my antenna is in the attic, the 6600 is in the basement. The router/switch is on floor 2, there is a switch on the first floor and one on the basement. The first floor switch is the biggest part of the problem. I made an RF sniffer out of a small toroid core with 10 turns of wire connected to a small $25 hand held scope. I used that to examine the switches, cables and power blocks all around the house. That enabled me to determine the noise sources and the freq. Then I picked ferrites. Many filters try to prevent rf from disturbing the Ethernet, my goal was to **** the 60Khz coming out of the switch.

Stan VA7NF

I have found the manufacturer makes a difference.  My understanding is that, for network hardware, cat5 did not require balanced transformers in their ports where cat6 does. 
Also watch out for ground loops and use STP or SSTP cables with one significance difference.  As mentioned above put a shield break in the line.  What I like to do is purchase SSTP Cat6+ cables, cut them in half, and install NON-shielded connectors on one end.  Then run the cables with ONLY the switch end having the shields.  With a remote switch, repeat the process ensuring the backbone feed has the non-shielded connection.  You now have a true balanced network with no rf ground loops.  I did replace my cisco/linksys devices with netgear because of their excessive RFI levels.
I also like all my remotes to be POE with a UPS on my POE enabled backbone; this keeps all the network up over power problems.
Also in other conversations, consider a fiber interconnect between public feed (read lightning isolation)  and your shack.  That protects you from your neighborhood, or for better public relations your neighbors from your antennae.