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@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@contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>
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