[RFI] Ethernet noise

[Jim Brown]

On 9/23/2023 9:20 AM, nlsa at nlsa.com wrote:
> I have several dB of broadband RFI in my 2m EME system.  I suspect that some
> of it results from ethernet cabling.  The station has about a dozen modules
> (SDR, transverter, SSPA, etc.) that are all connected to a central Ethernet
> switch.  I have used STP or S/FTP cables throughout but I am confused about
> how these cables should be grounded.  Should I defeat the shield ground by
> taping the outside of the connectors at one end?  If so, should it be at the
> Ethernet switch or the distal ends at each module?

They should not be "grounded," but the shields MUST be terminated to the 
shell of the connectors on PROPERLY manufactured switches. That means 
that everything about the equipment is properly manufactured. Properly 
manufactured means that the shells of those connectors must be bonded to 
the shielding enclosure at the point of entry, and that all conductors 
leaving the enclosure must be properly terminated, and conductors that 
are not shielded must exit via a feedthrough cap. I don't know anything 
about the quality of currently manufactured equipment, but my gut tells 
me it ain't the cheap stuff, and even expensive ain't guaranteed to be 
right.

73, Jim K9YC