LinkSys Routers and Ham Radio Interference! Another plague for the Ham Bands? Information And A Cure for RFI/EMI from LinkSys Routers and Their Products to Ham Radio? MAYBE! Multitudes of Ham Radio operators are reporting in various forums, interference in varying degrees from none, or minor, to MAJOR disruption to Ham Radio Bands from LinkSys products of all types! Hams worldwide are having problems associated with LinkSys products. The purpose of this page is NOT to downgrade or bash any manufacturer or product line....only to report what others have said and done about the known interference problems specific to the Ham Radio bands and the LinkSys products. There may be other brands causing interference also. Just a little FYI on the noisy wireless router problems causing interference to Ham Bands. Apparently this is a known issue with many Linksys routers and other products from LinkSys whether they are wireless or not and has been ongoing for a long time. We will attempt to give you information, some known models causing trouble, links, sources of discussion, tips, and hopefully at least one cure for Linksys product interference to the Ham Bands. There are other sources on the internet concerning these problems but we will give you some of the more popular ones. You can do a search and find lots more. More about the problem..... Some Hams are of the opinion that the whole bag of Linksys models is involved to one degree or another and that LinkSys knows about the problem but are not very helpful most of the time except in rare instances. Usually the support people just state that they are compliant with the FCC rules and regs and drop the subject! One interesting question is how did they ever get Type approval if they are so compliant in causing interference to a Licensed Service? Question unanswered as of this writing! Maybe LinkSys has the correct answer! Here are some statements taken from various sources of Ham radio operators concerning LinkSys products: "It seems that all LinkSys products have been produced with absolutely no shielding or RF bypassing of any kind and with total disregard to interference, RFI/EMI, caused to any other device." "Linksys products have got to be the worst on the market." "SOME MODELS CAN BE HACKED FOR INCREASED POWER" "My 2 meter rig is now happy that LinkSys junk is gone." "Frankly, I think these things are messier than a spark gap transmitter!" "These routers have also been known to shut down adjacent networks, cordless phones, hf rigs, pagers, baby monitors... you name it." "There's a ton of pages online about how it creates havoc on Amateur Frequencies." "Pure hash caused by trash" "Absolute Junk.....put it where it belongs....in the trash.! " "Disconnect it from power......problems are gone!" Editors note...this one says it all! "Try shielding the cables...may help some." "I will never by another LinkSys product again." "I have a LinkSys model  DI-524 router. With power on,  the router is breaking squelch on my 2m reciever over 30 feet away.  This is with the squelch full clockwise and scanning is out of the question.  With the router off, the Yaesu 7800 is performing as advertised." "The 624 is history as soon as I can get a replacement." And on and on. What models are involved? According to our research on the web using various forums, input from emails, bulletin boards, etc, as sources, these are the LinkSys models mentioned most of the time that create RFI/EMI to Amateur Radio Bands or frequencies: Models reported to be rfi producers....(including other LinkSys products).....this list is not all inclusive..there may be others: BEFSR41 wireless-g router "G" router + WAP BEFSR11 WRT54G Update....Models in Europe may not be problems ( "CE" marked according to Roger  MW0IDX  K3IDX)...thanks Roger! 10/100 hub from Linksys (Model EFAH05W) BEFSR1 BEFW11S4 D-524 Router D-Link, Model DI-624 ver.  E1. 4 ports & 108 G wireless..... Hash on 2 meters for 3 to 4 hundred feet away! NOW ONE (CURE)......HOPEFULLY! Taken from one of the forums and referring to a wireless LinkSys router courtesy of VE3VDC: "When I called their support line they not only knew all about it, they knew exactly who to put me on with for advice. Their support line is at 1-800-326-7114. The problem is that the cat5 cables radiate the ethernet switching hash from inside the router." (Editors Note...the keywords here are {INSIDE THE ROUTER}....THE SOURCE!) The third harmonics land on mid-VHF frequencies. Basically they suggested: 1) Set all NIC cards to 10 mbps. 2) Coil up extra cable length on a "three finger" form and tape. 3) Disable unused ports. 4) Make certain all connectors are clean and in good condition. 5) Keep the router at least 6 inches from metal objects. 6) Disconnect unused cables. This seems to have worked. No more washing machine sound every few Khz all across 2 meters... at least for now. Time will tell if this is a permanent solution. (fingers crossed) Source of these tips...VE3VDC See his excellent article "RFI From Computer Networks" here. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Some other good sources, forums, comments, etc concerning the problem with LinkSys products and Ham Radio: Note, The eham.net links below may require some rather long drawn out reading and sorting time to wade thru all the QRM in the articles. http://www.eham.net/articles/8302 http://www.hamforum.com/viewtopic.php?t=4952 http://www.eham.net/forums/RFI/361 But it doesn't end there... There's lots more on the internet! SOME TIPS IN TRACKING DOWN SOURCES OF RFI IN THE SHACK. These tips may help in locating severe noise sources to 2 meters and bands above that are suspected of coming from your radio or computer equipment. If the source strength is intense and fundamental frequency is low enough, this could be the source of all your ham band problems. Also see tips for HF below. Tips for VHF and above: Using a 2 meter handheld, adjust it to an unused frequency. Leave the "Rubber Duckie" antenna attached. Stand back several feet from the suspected device or if needed in another room or location if the white noise "floor" is too strong. Adjust the squelch just to the point that the white noise stops. Now move the handheld around or near each and every piece of equipment in your station that is near your router or associated cables. If the squelch breaks an noise poors from the receiver when you are very close to the suspect device...then you may have found the source! Now remove the antenna from the handheld remembering the device, cable, etc, that caused the squelch to break. Carefully move the antenna connector end of the handheld toward the device.......the noise should increase and break the squelch even higher as you get closer with the handheld if this is the source of the noise to 2 meters. (When you removed the antenna, you greatly decrease the "sensitivity" of the handheld. This helps in pinpointing the exact source.) If your handheld has a signal level meter, (S Meter), this will aid in tracking down the source with more accuracy than listening to the noise coming from the speaker. The stronger the reading, the closer you are. With the antenna disconnected, you will have to be close to the suspected device. Now leaving the handheld in the same position (don't move it), remove all cables from the suspect device except the power to the unit. If the noise stops or gets much weaker...one of more cables are most likely radiating trash rf from INSIDE THE DEVICE! Don't forget the cables going to the computer. Check them too. Your computer and associated devices, cables, etc may also be adding to your problem or could be the culprit! If you remove the power to the device.....all noise stops.....you have found your source! BEST Solution.....If it is a LinkSys device.......remove it from service and get another well known brand in a metal case with shielded cables if possible with known good shielding all around! Simple as that. Don't spend good money on extra shielded cables, ferrites, etc and just wasting your time....of course this is up to you. Troubleshooting and locating RFI on the HF Bands. Use a short length of coax connected to the antenna input of your HF rig with a very small "Sniffer" loop attached to the other end. In other words, build yourself a very small loop, about 1 or 2 inches in diameter, fed with 50 ohm coax leading to your HF rig antenna input......Don't key your transmitter while the loop is used for obvious reasons!!!!!! You will use the Hf receiver to help locate the suspected noisy device just like in the 2 meter procedure above using the "Sniffer" loop on the end of the coax. Make it long enough to reach all devices in your station. You may need to use attenuation and or RF gain to reduce your receiver sensitivity during this procedure. You want to have the least sensitivity the closer you get to the source of the noise to aid in pinpointing it. Check all bands and frequencies or the band that you are having the noise on by watching the S meter and listening to the audio from the receiver. Remember...the most simple thing to do in finding the culprit is to disconnect the power from each suspected device and if the noise stops.....you have located the source! Good luck More RFI Tips and Tricks....click here!. Notes from the Editor; You will notice in the response from LinkSys tech support to VE3VDC above, that they AKNOWLEDGED THAT THEY HAVE THE PROBLEM! We would like to thank L D Blake, VE3VDC for informing us of this problem concerning LinkSys products and the Amateur Bands. We usually do not report on concerns such as this but due to the severe nature of the problems with LinkSys and the Amateur Radio Bands, we hopefully can inform more people about what they may be getting into if they use LinkSys products in or near Amateur Radio Stations...... If YOU have any valuable input to this article pertaining to other models of LinkSys products interfering with Ham bands and/or known cures, please email us with the exact models and description of the interference. You may notice the Google ads on the left side of the page with LinkSys advertising.....we are not responsible for the Google ad content. They are sorted by Google as related to the content on this page. I doubt that any of you would be interested anyway in buying LinkSys products if you read this complete article and do your research! If you are still interested in LinkSys...just click on any of the ads. 73 N4UJW Hamuniverse.com     {n4ujw at hamuniverse.com}