Topband: Need More Help Getting rid of Router Birdies
hsgorden at comcast.net
Thu Feb 21 12:19:37 EST 2008
> Date: Wed, 20 Feb 2008 23:35:04 -0600
> From: Ed Gray W0SD <w0sd at triotel.net>
> Subject: Topband: Need More Help Getting rid of Router Birdies
> To: Topband at contesting.com
> Message-ID: <47BD0D88.1040103 at triotel.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> I got my $100.00 worth of type #43 ferrite that are exacty the ferrite
> that has been recommended for curing router birdes on this reflector. I
> have wrapped 9 turns of the CAT cable through and around the ferrite
> core and it makes absolutely no difference.
> Today three of us hams worked on the birdie problem for quite awhile.
> Here is what we found. It seems to be something to do with the birdies
> being generated in the computer, ie the circuitry that talks to the
> router. It happens with all my computers but on my newest one when you
> shut it off some circuitry stays powered up and the light on the network
> card stays on and the birdies only go away when you pull the AC cord off
> the computer.
> We took the side cover off the computer and the birdies do not get worse
> so more sheilding does not seem to be the answer. It is a good steel
> cabinet, well shielded. We unhooked everything from the computer other
> than the AC cord and the CAT cable and no change. We wrapped 9 turns of
> the AC power cord through the ferrite core and it made no difference.
> As I said having 9 turns of the CAT cable wrapped through the ferrite
> core makes no difference. We tried less turns and no change.
> On beam antennas aways from the house you can peak the signal by beaming
> on the house or lose the signal beaming away from the house. We tried
> different runs of CAT Cable seeing if it would change the signal
> strength thinking the CAT cable was acting as an antenna and it made
> absolute no difference.
> I also have an AC line filter on the computer which cured my switching
> power supply noise. We also tired the ferrite core on the power cord to
> the Router which was a desperation idea as our tests seem to indicate it
> is being generated in the computer if the router signal is coming into
> the computer. We hooked the DSL modem right to the computer and the
> birdies are gone. It would seem the birdies are being radiated by the
> CAT Cable and the ferrite is not attenuating it at all. I also tried a
> clip on ferrite and no effect. I don't have any shielded Network cable
> and all I read is that really should not be necessary.
> The birdies happen on all bands 160M through 10M. I have not checked
> six meters and above as I just moved into a new radio room and don't
> have those bands hooked up yet.
> We need some fresh ideas as we have ran out of ideas to try next. It
> happens with all three of my computers in this same way.
> I also have a laptop with a wireless card and it gives no problem(no
> birdies)as long as you don't have a CAT cable hooked to one of my three
> computers and as I said there is not problem if the computer is not on.
> The only solution so far that would seem to work is to buy a wireless
> card or the USB wireless adaptor for each desktop computer and forget
> the CAT cable. I base this on having no problem with using the wireless
> card in the laptop.
> Every computer hooked to the router has its own set of birdies so with
> three computers hooked up I have quite a number of birdies, some very
> loud depending on the antenna orientation. If I just have two on there
> are less and with just one on there are not all that many. I can rank
> the computers as to which produces the most birdies and the least.
> Does anyone have suggestions of things to try before trying the wireless
> connection? The birdie does at times have a bit of worble to it and it
> seems to be when the light is flashing on the Network card.
> Ed W0SD
1> You might want to try and shield all cables with tin foil.
2> You might want to try and shield the computer with tin foil as well as
router box, but not the router antennas.
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