On Thu, 11 Mar 2010, Rick Karlquist wrote:
> Christopher E. Brown wrote:
>>> What is the best method of getting rid of router birdies? I have a Cisco
>>> Linksys router with both wireless and wired connections. There's a long
>>> run (50ft) of unshielded CAT 5 cable going to the shack which I'll be
>>> replacing with shielded cable. I'm told the wallwart can be a source of
>>> RFI as well.
>> 2.4 inch Type 31 toroids, on the power and on each ethernet cable leaving
>> the device. For a long run put one on each end of the ethernet cable.
>> Consult Jims paper for the proper # of turns for max supression on the
>> freqs the birdies are bothering you.
> I had trouble with my LAN cable wiping out the AM broadcast band.
> It probably would have screwed up ham bands too, except it was too
> far away from the ham antennas. I just applied ferrite toroids to the
> LAN and power connections and that fixed it. Be sure to use big
> toroids with multiple turns. Don't try to use beads with one "turn"
> going through them.
> Rick N6RK
Agreed, 2.4in toroids and multiple turns. In my original case 3 turns
through a .4" id snapon (thin cable) made a dent, but I ended up with
10turns though a 2.4in type31 toroid on each ethernet cable before they
were "gone" (Gone being can only be just detected with preamps on, band
closed and a very low noise day)
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