Hello all,
The launch of Delfi-C3 has brought to my attention a very strong birdie at 145.930 MHz that clearly comes from the Linksys WRT54G Wireless router that sits in the shack. Forcing the wireless signal to another frequency/channel has no impact whatsoever...
Anybody on the list have a clever solution (other than 'get a different router' or 'move it' or 'shut it off', etc...hi hi) that they may have used for a similar problem?
Thanks,
Mark L. Hammond [N8MH]
Mark,
If they ever get around to using it, there is also a nice birdie on 145.870! My solution is to use ferrites on both the power and Ethernet cables from the router, and also use the mast mounted preamp. That is far enough away that the downlink swamps the birdie. Since most of the noise goes away when you unplug the Ethernet cable to the desktop, I have been considering switching that to RF as well, as I have an unused PCI card handy.
Alan WA4SCA
If they ever get around to using it, there is also a nice birdie on 145.870! My solution is to use ferrites on both the power and Ethernet cables from the router, and also use the mast mounted preamp. That is far enough away that the downlink swamps the birdie. Since most of the noise goes away when you unplug the Ethernet cable to the desktop, I have been considering switching that to RF as well, as I have an unused PCI card handy.
Another option beyond the ferrites may be to try a different power supply or AC adapter. Most of these routers are now using a small switching power supply, which are lighter and smaller than a traditional transformer-based wall-wart adapter would be for the same voltage/current requirement.
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/
On the other hand I had a problem with a wired Netgear hub. If I remember correctly the birdie was S9, and around 145.800 or right on the ISS Mir d/l. I had to unplug the wall wart from the hub to power it off, to work that frequency. It was the hub, not the power supply, or Ethernet cat5 cable. When I switched over to a hybrid (wired and 2.4 gig RF) Linksys router I was able to eliminate the wired hub that was causing the problem. I work AO51 L/S no problem. I still run wire to my main computer and also downstairs in my house as it is much faster than the Wireless G. How much faster? According to Speakeasy speed test, wired 28212/2696 kbps, best rf (6 feet away)10094/2646 kbps. BitTorrent notices a big difference!
I also tried several different hubs, from different manufactures, all three of them had the same birdie, the problem went away when I went wireless. Go figure...
73 Jeff kb2m
----- Original Message ----- From: "Alan P. Biddle" [email protected] To: [email protected] Sent: Tuesday, May 06, 2008 7:31 PM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
Mark,
If they ever get around to using it, there is also a nice birdie on 145.870! My solution is to use ferrites on both the power and Ethernet cables from the router, and also use the mast mounted preamp. That is far enough away that the downlink swamps the birdie. Since most of the noise goes away when you unplug the Ethernet cable to the desktop, I have been considering switching that to RF as well, as I have an unused PCI card handy.
Alan WA4SCA
Hi Jeff,
Same problem here...does anyone use shielded twisted pair CAT 5 cables? Does this help at all/a bit/not at all?
thanks
Graham G3VZV ----- Original Message ----- From: "jeff" [email protected] To: [email protected] Sent: Wednesday, May 07, 2008 12:49 PM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
On the other hand I had a problem with a wired Netgear hub. If I remember correctly the birdie was S9, and around 145.800 or right on the ISS Mir d/l. I had to unplug the wall wart from the hub to power it off, to work that frequency. It was the hub, not the power supply, or Ethernet cat5 cable. When I switched over to a hybrid (wired and 2.4 gig RF) Linksys router I was able to eliminate the wired hub that was causing the problem. I work AO51 L/S no problem. I still run wire to my main computer and also downstairs in my house as it is much faster than the Wireless G. How much faster? According to Speakeasy speed test, wired 28212/2696 kbps, best rf (6 feet away)10094/2646 kbps. BitTorrent notices a big difference!
I also tried several different hubs, from different manufactures, all three of them had the same birdie, the problem went away when I went wireless. Go figure...
73 Jeff kb2m
----- Original Message ----- From: "Alan P. Biddle" [email protected] To: [email protected] Sent: Tuesday, May 06, 2008 7:31 PM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
Mark,
If they ever get around to using it, there is also a nice birdie on 145.870! My solution is to use ferrites on both the power and Ethernet cables from the router, and also use the mast mounted preamp. That is far enough away that the downlink swamps the birdie. Since most of the noise goes away when you unplug the Ethernet cable to the desktop, I have been considering switching that to RF as well, as I have an unused PCI card handy.
Alan WA4SCA
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Graham:
With the Linksys device being plastic, I dont know how effective shielded cables would be. Not to mention they are usually more expensive than the non-shielded ones. Have you tried putting toroids on the network cables ? That might knock down the birdies a little bit. Might not be a bad idea to put a toroids on the power cable to the Linksys as well. Shouldnt need to but I am looking at possibilities.
Ron KA4KYI
Graham Shirville wrote:
Hi Jeff,
Same problem here...does anyone use shielded twisted pair CAT 5 cables? Does this help at all/a bit/not at all?
thanks
Graham G3VZV ----- Original Message ----- From: "jeff" [email protected] To: [email protected] Sent: Wednesday, May 07, 2008 12:49 PM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
On the other hand I had a problem with a wired Netgear hub. If I remember correctly the birdie was S9, and around 145.800 or right on the ISS Mir d/l. I had to unplug the wall wart from the hub to power it off, to work that frequency. It was the hub, not the power supply, or Ethernet cat5 cable. When I switched over to a hybrid (wired and 2.4 gig RF) Linksys router I was able to eliminate the wired hub that was causing the problem. I work AO51 L/S no problem. I still run wire to my main computer and also downstairs in my house as it is much faster than the Wireless G. How much faster? According to Speakeasy speed test, wired 28212/2696 kbps, best rf (6 feet away)10094/2646 kbps. BitTorrent notices a big difference!
I also tried several different hubs, from different manufactures, all three of them had the same birdie, the problem went away when I went wireless. Go figure...
73 Jeff kb2m
----- Original Message ----- From: "Alan P. Biddle" [email protected] To: [email protected] Sent: Tuesday, May 06, 2008 7:31 PM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
Mark,
If they ever get around to using it, there is also a nice birdie on 145.870! My solution is to use ferrites on both the power and Ethernet cables from the router, and also use the mast mounted preamp. That is far enough away that the downlink swamps the birdie. Since most of the noise goes away when you unplug the Ethernet cable to the desktop, I have been considering switching that to RF as well, as I have an unused PCI card handy.
Alan WA4SCA
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
I have seen some issues with hubs and switches, not usually from routers (have had a couple fail). I have not seen too many shielded CAT cables (I bet not cheap). You will find that CAT6 or CAT5E will give you the quietest cables (tightness of the twisted pairs). The newer cables usually have four different twist rates and a way of separating the pair to keep noise off of the each other. That was one of the reasons I have suggested these style cables. I do my own wiring, but I do have all of the right tools and I have certified my drops. Just a bad work habit ;-)
Hope that helps 73 Will WC2L
----- Original Message ----- From: "Graham Shirville" [email protected] To: "jeff" [email protected]; [email protected] Sent: Wednesday, May 07, 2008 9:28 AM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
Hi Jeff,
Same problem here...does anyone use shielded twisted pair CAT 5 cables? Does this help at all/a bit/not at all?
thanks
Graham G3VZV ----- Original Message ----- From: "jeff" [email protected] To: [email protected] Sent: Wednesday, May 07, 2008 12:49 PM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
On the other hand I had a problem with a wired Netgear hub. If I remember correctly the birdie was S9, and around 145.800 or right on the ISS Mir d/l. I had to unplug the wall wart from the hub to power it off, to work that frequency. It was the hub, not the power supply, or Ethernet cat5 cable. When I switched over to a hybrid (wired and 2.4 gig RF) Linksys router I was able to eliminate the wired hub that was causing the problem. I work AO51 L/S no problem. I still run wire to my main computer and also downstairs in my house as it is much faster than the Wireless G. How much faster? According to Speakeasy speed test, wired 28212/2696 kbps, best rf (6 feet away)10094/2646 kbps. BitTorrent notices a big difference!
I also tried several different hubs, from different manufactures, all three of them had the same birdie, the problem went away when I went wireless. Go figure...
73 Jeff kb2m
----- Original Message ----- From: "Alan P. Biddle" [email protected] To: [email protected] Sent: Tuesday, May 06, 2008 7:31 PM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
Mark,
If they ever get around to using it, there is also a nice birdie on 145.870! My solution is to use ferrites on both the power and Ethernet cables from the router, and also use the mast mounted preamp. That is far enough away that the downlink swamps the birdie. Since most of the noise goes away when you unplug the Ethernet cable to the desktop, I have been considering switching that to RF as well, as I have an unused PCI card handy.
Alan WA4SCA
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
On May 7, 2008, at 5:49 AM, jeff wrote:
L/S no problem. I still run wire to my main computer and also downstairs in my house as it is much faster than the Wireless G. How much faster? According to Speakeasy speed test, wired 28212/2696 kbps, best rf (6 feet away)10094/2646 kbps. BitTorrent notices a big difference!
What kind of residential service is that from? Only a very limited few regions in the US have deployed cable modem systems that will go that fast, and/or you're on something like Verizon FIOS (fiber optic). Nothing in the ADSL "realm" even comes close to those numbers.
Otherwise, I'd say the number is inaccurate... or the result of something being cached. Being that you're a 2-lander, you might be one of the lucky few, though...
Try www.speedtest.net also, it's a little "smarter" than Speakeasy's tester, but does require a Flash-capable web browser.
-- Nate Duehr, WY0X [email protected]
Well Nate I tried speedtest and I still get good numbers...
24270 kbps down and 2583 kbps up
For comparasion purposes I also ran Speakeasy again..
24637 kbps down and 2582 kbps up.
So the two speedtest's show the same results. I did like the speedtest site, it has a lot of good information. I see what your saying, I'm getting better service then most people get around the country. And Comcast Cable says they can give me faster access for 10 dollars more a month. What I have now is more then I need, so I'm happy. I think my home being out in the middle of no where in a mostly farmed 5 acre building lot zone has a lot to do with it! The only thing I miss is 3G service for my cellphone, I can get that 500 feet from my house, and almost everywhere else here on the Jersey Shore. Also my Comcast cable system was installed in this area only about 8 years ago, so I guess it is fairly new, but hasn't been updated since then as far as I know. One more thing I didn't specifically mention is that of course I tried removing the cables from my metal cased Netgear hub. The rf was coming from the hub itself.
73 Jeff kb2m
----- Original Message ----- From: "Nate Duehr" [email protected]
On May 7, 2008, at 5:49 AM, jeff wrote:
L/S no problem. I still run wire to my main computer and also downstairs in my house as it is much faster than the Wireless G. How much faster? According to Speakeasy speed test, wired 28212/2696 kbps, best rf (6 feet away)10094/2646 kbps. BitTorrent notices a big difference!
What kind of residential service is that from? Only a very limited few regions in the US have deployed cable modem systems that will go that fast, and/or you're on something like Verizon FIOS (fiber optic). Nothing in the ADSL "realm" even comes close to those numbers.
Otherwise, I'd say the number is inaccurate... or the result of something being cached. Being that you're a 2-lander, you might be one of the lucky few, though...
Try www.speedtest.net also, it's a little "smarter" than Speakeasy's tester, but does require a Flash-capable web browser.
-- Nate Duehr, WY0X [email protected]
Did anyone hear AO-51 s mode d/l on the eastcoast 1420z pass ? My d/l converter seems to be powering up, but nothing heard here in FM29. Was it off, or do I need to fix my downconverter? Thanks for any useful information.
73 Jeff kb2m
I worked 2 stations on the pass. The bird had quite a bit of spin to it so it was going in and out. What are you using for a downconverter and antenna ?
Ron KA4KYI
jeff wrote:
Did anyone hear AO-51 s mode d/l on the eastcoast 1420z pass ? My d/l converter seems to be powering up, but nothing heard here in FM29. Was it off, or do I need to fix my downconverter? Thanks for any useful information.
73 Jeff kb2m
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Well I got everything working, hearing my d/l fine between the fades, had a great chat with myself. I guess everyone else on the Eastcoast was out to dinner or something. That's where I'm heading, taking my son Jeff's Mom of the week out to dinner. l hope everyone had a great mothers day....
73 Jeff kb2m
----- Original Message ----- From: "jeff" [email protected] To: "Amsat-Bb" [email protected] Sent: Friday, May 09, 2008 10:29 AM Subject: [amsat-bb] AO-51
Did anyone hear AO-51 s mode d/l on the eastcoast 1420z pass ? My d/l converter seems to be powering up, but nothing heard here in FM29. Was it off, or do I need to fix my downconverter? Thanks for any useful information.
73 Jeff kb2m
I can suggest a couple of things... Internal or external P/S.... Internal, try torroids. external (wall worth) try a different P/S. Use only high quality CAT5E or CAT6 cables. Do not use cheap ones! There is a difference.
WRT54G can be vastly improved by installing the Linux based OS. I have a better signal, lower noise and better security. I am much happier. Worth trying (it will void any warranty).
That is what I can offer. Hope it helps, Will WC2L
----- Original Message ----- From: "Mark L. Hammond" [email protected] To: [email protected] Sent: Tuesday, May 06, 2008 6:58 PM Subject: [amsat-bb] "Birdies" from Linksys Wireless router
Hello all,
The launch of Delfi-C3 has brought to my attention a very strong birdie at 145.930 MHz that clearly comes from the Linksys WRT54G Wireless router that sits in the shack. Forcing the wireless signal to another frequency/channel has no impact whatsoever...
Anybody on the list have a clever solution (other than 'get a different router' or 'move it' or 'shut it off', etc...hi hi) that they may have used for a similar problem?
Thanks,
Mark L. Hammond [N8MH]
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Hello all,
The launch of Delfi-C3 has brought to my attention a very strong birdie at 145.930 MHz that clearly comes from the Linksys WRT54G Wireless router that sits in the shack. Forcing the wireless signal to another frequency/channel has no impact whatsoever...
Anybody on the list have a clever solution (other than 'get a different router' or 'move it' or 'shut it off', etc...hi hi) that they may have used for a similar problem?
Thanks,
Mark L. Hammond [N8MH]
I don't use any wireless device around the shack too much problem with the birdies and noise (Good old RJ-45 blue cable only) . On 2.4ghz i have to switch off my X-10 wireless camera i got a S9 pLus 40 of a steady noise carrier.
Luc Leblanc VE2DWE Skype VE2DWE www.qsl.net/ve2dwe WAC BASIC CW PHONE SATELLITE
I have the WRT54G Wireless router and find NO birdies at 145.93 or anywhere in the 145 MHZ range.
----- Original Message ----- From: "William Liporace - NA2NA" [email protected] To: [email protected]; "Mark L. Hammond" [email protected] Sent: Tuesday, May 06, 2008 7:55 PM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
I can suggest a couple of things... Internal or external P/S.... Internal, try torroids. external (wall worth) try a different P/S. Use only high quality CAT5E or CAT6 cables. Do not use cheap ones! There is a difference.
WRT54G can be vastly improved by installing the Linux based OS. I have a better signal, lower noise and better security. I am much happier. Worth trying (it will void any warranty).
That is what I can offer. Hope it helps, Will WC2L
----- Original Message ----- From: "Mark L. Hammond" [email protected] To: [email protected] Sent: Tuesday, May 06, 2008 6:58 PM Subject: [amsat-bb] "Birdies" from Linksys Wireless router
Hello all,
The launch of Delfi-C3 has brought to my attention a very strong birdie at 145.930 MHz that clearly comes from the Linksys WRT54G Wireless router that sits in the shack. Forcing the wireless signal to another frequency/channel has no impact whatsoever...
Anybody on the list have a clever solution (other than 'get a different router' or 'move it' or 'shut it off', etc...hi hi) that they may have used for a similar problem?
Thanks,
Mark L. Hammond [N8MH]
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Hey, lucky you! Want to trade? :)
I found one cable that was causing much of the noise--I got it down from about S7 (!!!) to S1-2. Still a ways to go...
What hardware and firmware version are you running? Mine is Version 5 hardware, with current firmware (some silly long number ;-) )
73,
Mark
----- Original Message ----- From: "Rick Vidmar - K9KK" [email protected] To: "William Liporace - NA2NA" [email protected], [email protected], "Mark L. Hammond" [email protected] Sent: Wednesday, May 7, 2008 10:06:11 AM (GMT-0500) America/New_York Subject: Re: [amsat-bb] Re: "Birdies" from Linksys Wireless router
I have the WRT54G Wireless router and find NO birdies at 145.93 or anywhere in the 145 MHZ range.
----- Original Message ----- From: "William Liporace - NA2NA" [email protected] To: [email protected]; "Mark L. Hammond" [email protected] Sent: Tuesday, May 06, 2008 7:55 PM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
I can suggest a couple of things... Internal or external P/S.... Internal, try torroids. external (wall worth) try a different P/S. Use only high quality CAT5E or CAT6 cables. Do not use cheap ones! There is a difference.
WRT54G can be vastly improved by installing the Linux based OS. I have a better signal, lower noise and better security. I am much happier. Worth trying (it will void any warranty).
That is what I can offer. Hope it helps, Will WC2L
----- Original Message ----- From: "Mark L. Hammond" [email protected] To: [email protected] Sent: Tuesday, May 06, 2008 6:58 PM Subject: [amsat-bb] "Birdies" from Linksys Wireless router
Hello all,
The launch of Delfi-C3 has brought to my attention a very strong birdie at 145.930 MHz that clearly comes from the Linksys WRT54G Wireless router that sits in the shack. Forcing the wireless signal to another frequency/channel has no impact whatsoever...
Anybody on the list have a clever solution (other than 'get a different router' or 'move it' or 'shut it off', etc...hi hi) that they may have used for a similar problem?
Thanks,
Mark L. Hammond [N8MH]
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
I successfully supplemented my ferrites by threading the phone cable to the modem/router down a length of tightly woven co-ax braid, grounded to the modem ground one end and the mains earth at the other.
I suspect that you are hearing the CPU or clock running since I get it also all over the HF bands also.
I turn it off but that is a pain. I'll try the ferrites on the wiring.
Someone point me to more info on the Linux SW for the router?? Sounds like something to do regardless.
KU8L Curt
Mark L. Hammond wrote:
Hello all,
The launch of Delfi-C3 has brought to my attention a very strong birdie at 145.930 MHz that clearly comes from the Linksys WRT54G Wireless router that sits in the shack. Forcing the wireless signal to another frequency/channel has no impact whatsoever...
Anybody on the list have a clever solution (other than 'get a different router' or 'move it' or 'shut it off', etc...hi hi) that they may have used for a similar problem?
Thanks,
Mark L. Hammond [N8MH]
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
On May 6, 2008, at 4:58 PM, Mark L. Hammond wrote:
Hello all,
The launch of Delfi-C3 has brought to my attention a very strong birdie at 145.930 MHz that clearly comes from the Linksys WRT54G Wireless router that sits in the shack. Forcing the wireless signal to another frequency/channel has no impact whatsoever...
Anybody on the list have a clever solution (other than 'get a different router' or 'move it' or 'shut it off', etc...hi hi) that they may have used for a similar problem?
Thanks,
Mark L. Hammond [N8MH]
Mark,
My Linksys WRT54GS annoyed the heck out of me with birdies, so I replaced it with a cheap Netgear. Not a peep out of it, since then.
I liked having DD-WRT on the Linksys device a couple of years ago when I was using it, but the Linksys is stashed away in a box for "emergencies" and otherwise banned from my shack now, due to the RF issues.
Ironically I had already tried the "power the house down to see if the interference is local" and had decided it wasn't, and that I needed to do some DF'ing... then I realized that the server and the WRT54GS were on the UPS, which I had NOT shut off. (Doh! Smacks forehead...)
I did try briefly to do things like ferrites on the "goes-intas" and "goes-outtas", etc... to no perfect effect. I could mitigate some of the noise, but the thing was ultimately just too noisy. The wall- wort for my particular model (there are something like six different hardware models of the WRT54GS -- another annoying pattern of the small router manufacturers) was just a transformer... whether or not there was a noisy switch-mode power supply inside the Linksys, I didn't investigate.
Someone else commented about using "quality Cat 5 and Cat 6 cable"... since Cat 5 and Cat 6 are ratings for UNSHIELDED twisted-pair (UTP), I have no idea what differing "quality" levels of cable would accomplish. Ethernet via Cat 5 is SUPPOSED to leak signal. Someone missed reading the standards, I guess. The comment made no sense to me from an RF engineering perspective.
One possible "fix" for that type of noise could be to run Ethernet on SHIELDED twisted-pair (STP) cable, and ground the "drain" wire at ONE end (don't ground both ends, you WILL create a ground loop, and it WILL drive you crazy... eventually) but it no longer will meet the Ethernet specifications for cross-talk, etc. Frankly, it works -- but don't go doing it in the office or someplace where the network is critical. They make special RJ45 connectors with metal strips "wrapped around" the connector body that can be crimped in such a way as to capture the drain wire, and that are built to ground to special female RJ45 sockets... again, only do this on one end... and they were usually used for things like telco T1 carriers that *are* specified to use STP cabling in many instances.
I don't think the real noisemaker in the Linksys was the Ethernet signal itself anyway -- it certainly leaked out of the cheap plastic (virtually unshielded) case via the Ethernet cablilng, but the Ethernet noise wasn't the problem. It was so cheap to try another router, the "fixes" weren't worth my time. Easier to buy from Netgear who's had a pretty good track record of actually building properly shielded products, back to when their little switches, hubs, and other devices were all in the "blue metal case", complete with a real ground terminal and lug on the back-side, which is a "body style" they're not making many of anymore...
Same thing with cheap plastic PC cases... noise galore leaking from those, too. Makes one miss the days of steel cases and PCs you could barely lift.
My IBM/Lenovo T43 provided by work throws all sorts of VHF crud, enough to completely obliterate the front-end of my poor Kenwood TH- F6A "broad as a barn door" receiver on most of the VHF band (IF mixing perhaps), and the MacBook is more bearable, but the LCD backlight system makes RF noise.
I guess with the ever-lowing price of fiber-optic based networking gear... that's the ultimate in quiet, as long as you can keep the routers/switches themselves from leaking crud... but that's definitely overkill. Overkill is sometimes what we hams do best, however. I have seen the photos to prove it. (GRIN) We are the only HOBBY organization that regularly launches satellites... or so I'd like to believe. (BIGGER GRIN)
Good luck killing off the Linksys RF interference gremlins. Netgear highly recommended!
-- Nate Duehr, WY0X [email protected]
I found this topic interesting since I too have a Linksys WRT54G router, which is also in the shack. I decided to listen for the "birdies". I tuned to 145.93 mHz on the HT while sitting in the chair and.....nothing. Hmmm. So I stood up and moved around then lo and behold a strong birdie as I got very near the router. I did notice one thing, the birdie completely disappears about 2 to 2.5 feet from the unit. My router is on one side of the room about 12 to 13 feet away from the desk. I have absolutely no copy of the birdie with the HT on the desk. A possible solution could be if you have a large enough room, move the router off of and away from the desk with the VHF equipment on.
73,
Jeff WB3JFS
----- Original Message ----- From: "Nate Duehr" [email protected] To: "Amsat-Bb" [email protected] Sent: Thursday, May 08, 2008 11:58 PM Subject: [amsat-bb] Re: "Birdies" from Linksys Wireless router
On May 6, 2008, at 4:58 PM, Mark L. Hammond wrote:
Hello all,
The launch of Delfi-C3 has brought to my attention a very strong birdie at 145.930 MHz that clearly comes from the Linksys WRT54G Wireless router that sits in the shack. Forcing the wireless signal to another frequency/channel has no impact whatsoever...
Anybody on the list have a clever solution (other than 'get a different router' or 'move it' or 'shut it off', etc...hi hi) that they may have used for a similar problem?
Thanks,
Mark L. Hammond [N8MH]
Mark,
My Linksys WRT54GS annoyed the heck out of me with birdies, so I replaced it with a cheap Netgear. Not a peep out of it, since then.
I liked having DD-WRT on the Linksys device a couple of years ago when I was using it, but the Linksys is stashed away in a box for "emergencies" and otherwise banned from my shack now, due to the RF issues.
Ironically I had already tried the "power the house down to see if the interference is local" and had decided it wasn't, and that I needed to do some DF'ing... then I realized that the server and the WRT54GS were on the UPS, which I had NOT shut off. (Doh! Smacks forehead...)
I did try briefly to do things like ferrites on the "goes-intas" and "goes-outtas", etc... to no perfect effect. I could mitigate some of the noise, but the thing was ultimately just too noisy. The wall- wort for my particular model (there are something like six different hardware models of the WRT54GS -- another annoying pattern of the small router manufacturers) was just a transformer... whether or not there was a noisy switch-mode power supply inside the Linksys, I didn't investigate.
Someone else commented about using "quality Cat 5 and Cat 6 cable"... since Cat 5 and Cat 6 are ratings for UNSHIELDED twisted-pair (UTP), I have no idea what differing "quality" levels of cable would accomplish. Ethernet via Cat 5 is SUPPOSED to leak signal. Someone missed reading the standards, I guess. The comment made no sense to me from an RF engineering perspective.
One possible "fix" for that type of noise could be to run Ethernet on SHIELDED twisted-pair (STP) cable, and ground the "drain" wire at ONE end (don't ground both ends, you WILL create a ground loop, and it WILL drive you crazy... eventually) but it no longer will meet the Ethernet specifications for cross-talk, etc. Frankly, it works -- but don't go doing it in the office or someplace where the network is critical. They make special RJ45 connectors with metal strips "wrapped around" the connector body that can be crimped in such a way as to capture the drain wire, and that are built to ground to special female RJ45 sockets... again, only do this on one end... and they were usually used for things like telco T1 carriers that *are* specified to use STP cabling in many instances.
I don't think the real noisemaker in the Linksys was the Ethernet signal itself anyway -- it certainly leaked out of the cheap plastic (virtually unshielded) case via the Ethernet cablilng, but the Ethernet noise wasn't the problem. It was so cheap to try another router, the "fixes" weren't worth my time. Easier to buy from Netgear who's had a pretty good track record of actually building properly shielded products, back to when their little switches, hubs, and other devices were all in the "blue metal case", complete with a real ground terminal and lug on the back-side, which is a "body style" they're not making many of anymore...
Same thing with cheap plastic PC cases... noise galore leaking from those, too. Makes one miss the days of steel cases and PCs you could barely lift.
My IBM/Lenovo T43 provided by work throws all sorts of VHF crud, enough to completely obliterate the front-end of my poor Kenwood TH- F6A "broad as a barn door" receiver on most of the VHF band (IF mixing perhaps), and the MacBook is more bearable, but the LCD backlight system makes RF noise.
I guess with the ever-lowing price of fiber-optic based networking gear... that's the ultimate in quiet, as long as you can keep the routers/switches themselves from leaking crud... but that's definitely overkill. Overkill is sometimes what we hams do best, however. I have seen the photos to prove it. (GRIN) We are the only HOBBY organization that regularly launches satellites... or so I'd like to believe. (BIGGER GRIN)
Good luck killing off the Linksys RF interference gremlins. Netgear highly recommended!
-- Nate Duehr, WY0X [email protected]
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (13)
-
Alan P. Biddle -
Curt Nixon -
Graham Shirville -
jeff -
Jeff Yanko -
Luc Leblanc -
Mark L. Hammond -
Nate Duehr -
Nigel A. Gunn G8IFF/W8IFF -
Patrick STODDARD (WD9EWK/VA7EWK) -
Rick Vidmar - K9KK -
Ronald Nutter -
William Liporace - NA2NA