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1-10 of 13 messages
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VDSL activated in neighborhood, bad QRN/RFI
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by WB0GAZ on December 13, 2008
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The local phone company (Qwest) last week turned up VDSL (7-20 megabit DSL) service in my neighborhood (which has underground utilities.) I'm now experiencing broadband noise across HF bands which is strong enough to overwhelm most HF signals I could previously hear (noise is S7-S9; my antennas are dipole, vertical, etc. - all are affected similarly.) Temporarily disconnecting the phone line at the back yard pedestal didn't change things, and powering down the whole house didn't change things. Has anyone experience with VDSL-generated QRN/RFI?
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RE: VDSL activated in neighborhood, bad QRN/RFI
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by W1AEX on December 17, 2008
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I have no personal experience with what you are going through, however, I have spoken with 3 different hams in the past couple of weeks who are experiencing ham radio related issues with the ATT U-Verse package, which is also a VDSL product. In all three cases, the U-Verse package was of the FTTN variety which is fiber to the node and then twisted pair (copper) for the last 2500 feet throughout the neighborhood.
It appears that these FTTN installations are very susceptible to ingress from the HF spectrum between 1.1 - 12 mHz. According to the hams I spoke with, when they were operating on 160 meters through 40 meters, even with RF levels at or below 100 watts, they were severely disrupting nearby U-Verse installations. STB's crashed, internet and phone connections were dropped, and video was frozen, tiled, or simply went to a black screen.
To date, attempts by ATT to resolve these particular problems have not been successful. Filtering is not really an option since ATT is sending RF between 1.1 - 12 MHz over CAT3, or if you're lucky, the more interference resistant CAT5 twisted pair. Attempts to filter out RF from the HF spectrum will also filter out the IPTV - internet - phone signals that are supposed to be there. From what I have read in various forums, it has been reported that some U-Verse subscribers are even experiencing ingress by SW broadcasters from the 4 mHz - 11 mHz bands when propagation is really rocking.
I have not heard of egress issues such as what you are experiencing, but I guess it doesn't surprise me that it could be a problem. It might be an improper installation, or equipment failure somewhere in the neighborhood that could be resolved by the company. The phone companies do seem to like switching power supplies in their systems, and some of them can spray quite a bit of noise around. At any rate, I am hopeful that FTTN VDSL never finds a foothold in my neighborhood. I currently enjoy a cable connection for HDTV, phone, and internet that has proven to be immune to ingress/egress issues over the years.
I always hold my breath during the Christmas season, wondering what new Walmart "entertainment device" (telephone, plasma tv, battery charger, touch lamp, etc) is sitting under some neighbor's Christmas tree, just waiting to be unwrapped so it can begin spraying the ether with garbage.
FTTN "entertainment packages" from the phone companies looks to me like another rats nest ready to fall on our heads. Anyone else hear anything about this issue?
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RE: VDSL activated in neighborhood, bad QRN/RFI
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by AA5TB on May 12, 2009
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I have AT&T Uverse. As a service, it is fine. However, it is very susceptible to even QRP levels of RF and it generates RFI at least up to 2m. AT&T is very responsive to trouble calls but they have no idea how to fix the problems. When it was first installed they used coax from the Modem/Wi-Fi Router and I wiped it out when I transmitted above 10 MHz. I converted everything to Ethernet at my own expense (because they couldn't figure out how to run the cables) and then everything below 10 MHz was wiped it out. After I installed a common-mode filter out at the phone box and they replaced the router and a receiver twice the system now only gets wiped out on 160m and 80m. By the way, I usually operate QRP but sometimes I will use 100W.
It appears to me that the "2Wire" brand Modem/Router they use is the main RFI generator. There is no label indicating any kind of FCC type acceptance whatsoever. I think they are just getting the cheapest units they can get from China.
If you are thinking about getting this service just remember it is about as bad as BPL as far as RFI is concerned.
73,
Steve - AA5TB
Fort Worth, Texas
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RE: VDSL activated in neighborhood, bad QRN/RFI
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by WB4BYQ on May 14, 2009
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I am not sure how VDSL works, but my DSL was having
problems when i was on 75 meters and sometimes on 40.
What I did was to look at the phone lines thru out the house and install comman telephone filer at the house
outside box going only to the phones, not the dsl modem. i found that the phone lines were acting like
1/2 wave dipoles from the house connection box. the line from the pole to the box and the line to the phone as the other part of the ant. i did not use the dsl filter as the common phone rf filter. I used the k-com wired in filter. this broke up the wires for rf and now i can use the 80 and 40 meter bands. if the phone line is very long you might have to break it in the middle with a rf filter. also, i have found that shielded cat 5 cable works alot better for reducing rfi from routers, computers, modems, etc. be sure to use the shielded cat 5 connectors and tie the shield to the case ground at each end, or to ground point.
don't forget the type 31 snap on cores, like the ones
from olympixcorp.com or rfichoke.
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RE: VDSL activated in neighborhood, bad QRN/RFI
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by NO9E on August 16, 2009
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I got U-verse without reading comments about RFI that it causes.
There is higher noise level during the day than at night. Disconnecting the cable from the house does not change anything. The noise is S3-5.
Hard to say whether the extra noise is surely due to VDSL as I have lots of extra noises from power line. But the current mixture seem more across the board.
With limited testing, 1 KW affects one TV but not the other. 100W is fine.
Wonder whether I am the first with U-verse in the neighborhood. If so, switching back to cable would work. But if neighbors become U-verse clients this will not help. Forget running in contests where ability to dig out weak signals is crucial.
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RE: VDSL activated in neighborhood, bad QRN/RFI
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by W1AEX on August 16, 2009
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I continue to be hopeful that U-Verse never makes it out to my location. Currently, my end of the town is too far away from the fiber node that serves the DSLAMs for the more densely populated parts of town.
There is a limited bandwidth DSL offering in my neighborhood but nothing else. It is quiet enough here that I can hear a bit of DSL "data whine" from the top end of the broadcast band through 40 meters. It doesn't even move the S-meter on the receiver, but it's there, especially when shortwave listening in the AM mode.
When I head across town to grab a cup of coffee in the morning, I often listen to the AM broadcast band. I can tell immediately when I cross over to where U-Verse is available. There is all kinds of data and synch buzz noise bubbling away in the background of stations from the middle of the band to the top end. Even our local 50KW station, 15 miles away, suffers from heavy interference on one particular stretch. I guess no one in those neighborhoods listen to the broadcast band any more, or they believe that all that noise is just the way it's supposed to be...
At any rate, the egress is not supposed to be there. I would not hesitate to notify the installer in your neighborhood, to bring it to their attention. I would suggest you call them and notify them in writing to document your complaint.
One conversation I had with an ATT employee sticks in my mind. He simply said that U-Verse was designed to be a fiber product. The concept of sending it over copper twisted-pair is at best, a dubious endeavor.
I hope you have success with getting them to clean it up.
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RE: VDSL activated in neighborhood, bad QRN/RFI
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by NO9E on August 16, 2009
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Would writing to a neighborhood newsletter to avoid U-verse help, or will it make things worse?
My quad and other antennas are visible, and lots are pretty large, 3/4 acre. So I am already exposed.
Ignacy
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RE: VDSL activated in neighborhood, bad QRN/RFI
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by W1AEX on August 16, 2009
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Personally, I would urge you to work with the U-Verse provider to correct egress and ingress issues you are experiencing. They are selling a product and people are paying good money for that product. They have the responsibility for ensuring that what they sell is working correctly. I would avoid making any written statements in a neighborhood publication that could prove awkward for you at some point.
I would be very sure to document all contacts you have with their technicians as they work to correct the issues you report to them. Hopefully, they can correct the interference to the one susceptible TV in your installation, and then begin to work at reducing the incidental emissions that are interfering with your receive capabilities. If you begin to receive reports from neighbors that your transmissions are degrading their U-Verse experience, politely refer them to the company they are paying for the service.
It may take time, but keep working with the U-Verse provider as it is their responsibility to correct any issues with their equipment and installation.
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RE: VDSL activated in neighborhood, bad QRN/RFI
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by WA7NCL on August 17, 2009
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The information you provided does not prove DSL interference. I had a similar problem which seemed to eminate from the phone lines. I searched around with a portable AM and shortwave radio and found it comming from a transformer vault that also had a cable amp. I thought it was the Commcast cable amp power supply or something. It actually was trouble shot by the power company, who found it was a bad GFI in one of my neighbors bathrooms. It was travelling over the underground power lines and coupling to the underground phone and cable.
So before you are so sure its DSL, try to get the power company to help as well and investigate the neighborhood with a portable radio.
I have 3mbps service DSL and numerous routers switches, a homeplug system and HPNA in my house, and I find the various wall warts, computers and high def TVS in the neighborhood are much worse.
Most of the other posters are giving information about susceptability rather that emmissions. They are two different problems.
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RE: VDSL activated in neighborhood, bad QRN/RFI
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by WX7G on August 19, 2009
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WA0GAZ: Can you give us an update on your VDSL problems?
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