D. Kemp wrote:
>I have a home network with a cable modem connected to
>a D-Link router, then from there to 1 computer and to
>a wireless hub ( not on all the time) and to a Netgear
>hub in my shack that supplies 2 computers there.
>
>I am getting birdies from the Netgear hub. If I unplug
>the dc the RFI goes away. The hub is about 4 feet from
>the rigs. There is a ground wire on the hub. There is
>cat5 cable to and from the hub.
>
>Any ideas on how I can eliminate the RFI?
>
>
Yep. Get the biggest, meanest type 31 or 43 ferrites you can find /
afford and push as many turns of your cat5 cable through one at *each
end* of *each cable*. You may need to double or triple the length of
any short cables you're using. Also do the same thing for the leads
from any and all wall-warts you're using in your network. If you do it
right, your wall-warts will have to be no more than a foot or two from
the hubs and switches they're powering.... :-) Forget about the
ground wires.
All your networking cables are acting as antennas for the ethernet
frequencies. I have found with my various ethernet equipment that if I
common-mode ferrite filter power cables and ethernet cables and even the
DSL phone line just before it enters my DSL modem my MF/HF hamming at
1500 watts and my high-speed internet and home network can coexist
peacefully. (Without the filters, I got garbage at discrete ethernet
carrier frequencies on various ham bands and my 1500 watts on 160 used
to reset the DSL modem.)
Bud, W2RU
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|