[RFI] Ethernet RFI Elimination?

[Martin Ewing]

There are spurs everywhere, if you look deeply enough,
like every 32 kHz.  See
http://www.aa6e.net/aa6e/rfi/ether_details.html

I have tried the following -

-Used Cat5 shielded twisted pair
-Wrapped 5 or 6 turns of Cat 5 through type 43 ferrite
cores
-Put ferrite cores (6-9 turns) on the power leads for
hubs, switches, and other devices.  Lots of RF can
escape via the power leads.

All together, these have tamed the problem fairly well
for me.  I found I had to work just as hard at
shielding the non-Ethernet computer wiring.

WiFi and/or fiber optics are much more ham-friendly.

-73, Martin, AA6E

--- Eric Rosenberg <wd3q at starpower.net> wrote:

> I have a 3-computer/single printer wired network
> (using a Linksys
> router/print server) in my house.  For a variety of
> reasons, I can't run
> a wireless network. 
> 
> Jim Brown, K9YC, posted an interesting item this
> past month that touched
> on RFI generated by Ethernet (CAT5) cabling.  In the
> post, Jim mentioned
> some specific birdie frequencies.  I dialed them up
> on the Orion and, lo
> and behold, there they were. 
> 
> My questions are: 
> 
> What other frequencies will I hear the Ethernet (I
> believe Jim's posting
> stops at 10 MHz)?  
> 
> What can I do to lower/eliminate the RFI?  The
> router is about 20 feet
> away from the radio, the shack computer, cable modem
> and local printer
> are within 3 feet of the radio. 
> 
> Thanks in advance, 
> 
> Eric W3DQ
> Washington, DC 
> 
> _______________________________________________
> RFI mailing list
> RFI at contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>