RFI:Take a 2 minute ride through the interference... RESOLVED

[W1AEX]

I count my blessings that this noise is not in my neighborhood. At this time the source of the interference has not been determined. It could be an issue with the powerline hardware installed during a rebuild of the area's neighborhood distribution poles, or possibly something deployed by ATT with its FTTN service, or even one of the infamous and very dirty satellite receivers. It could even be a blown ground or lightning arrestor somewhere along the line. At any rate, the challenge here is to get one of the utilities involved to take a look to determine what is going on.

The odd thing about this particular problem is that it is quite frequency specific. The noise appears to begin sharply at 1.0 MHz with many buzzy oscillations up through 1.4 MHz. From there, random buzzy oscillations can be found up as high as the 20 meter band. Several much weaker buzzy oscillations can be heard in the lower section of the broadcast band. The noise can be detected along a 1.2 mile section of the road in the video, where they severely interfere with several very strong AM broadcast stations.

The video is roughly 2.5 minutes long. If you expand the notes under the video, you will see a fairly long narrative about the problem. The short story is that at some points in that area, the interference between 1.0 MHz and 1.4 MHz is powerful enough to obliterate the local 50,000 watt clear-channel broadcaster (WTIC) at 1.080 MHz, which is only 15 miles away.

http://www.youtube.com/watch?v=bKs8I-bPyRM

I would suggest that you view it in full screen so you can enjoy the spring foliage starting to bloom here in Connecticut country! Apologies for my dirty windshield, but I'm too lazy to wash it!

[W3RSW]

That station deserved to be wiped out. 

Man, that interference is pretty horrendous. Thanks for the informational ride.

[W8IXY]

As a broadcaster, as well as an amateur radio operator, I continue to be disappointed and even angered with the attitude of some companies that cause severe interference to existing services, and the frequency specific type of interference caused by the U Verse system can't be legal....can it?

Several days ago, I answered a knock on my door (typical suburban neighborhood - 60' x 120' smaller lots), and faced a door to door sales guy who was trying to convince me to subscribe to a "bundle" from AT&T to include TV, internet access and telephone.  I already had heard from several associates that they had signed up for U Verse, and after several months, when AT&T couldn't make it work, demanded its removal.

The door to door sales guy said something like, "...you have probably seen all of our AT&T trucks in the neighborhood installing our newest fiber network...."  No, I didn't.  He was quite persistent in selling the bundle for phone, TV, and internet, but I wasn't interested.

Now, with this video, I am concerned that one day soon, I may turn on my rig and hear all that buzzing and other crap from leaky, wired systems.  Right now, Its relatively quiet RF wise, with occasional buzz and crackling from power lines and who knows what else the neighbors have running.  I hope my "luck" with relatively low man made noise in this neighborhood holds out.

I would recommend that anyone, ANYONE, who experiences man made interference to their attempts to listen to anything in the RF spectrum, IMMEDIATELY begin the tracking down of the noise, reporting to the the "noise causer", and if no effort is made to eliminate that noise within 30 -60 days (more or less-your choice), to file a complaint with the FCC.  Make your own noise to the offensive companies.

The response referred to by W1AEX from AT&T is simply unacceptable.  That attitude from AT&T should spark (!) a detailed, complete response from anyone affected by the noise, both to the responsible company, and to the FCC if the offending company appears to send along the idea of "Tough luck, Buddy..."

It seems like we get into a situation of "You can't fight City Hall", with much of this interference.  But we also can't just sit there and do nothing.

W1AEX....call the chief engineer AND general manager of WTIC.  Report that you can no longer listen to your "favorite station", and explain why.  Also tell them of the attitude you got from AT&T.   It may not get anything done overnight, but at least you will plant a seed into the ears of the affected station's management.  After that, you never know where it might lead.....the manager may be friends with a local AT&T big boss, etc.

If any of us never do anything that interferes with our ability to listen to the ethereal waves, then the offending companies will push those interference generators harder and harder until the RF pollution renders off-air listening impossible.

73 - Ted  -  W8IXY
&
"Good Night and Good Luck" - Edward R. Murrow

[k4kyv]

First of all, I would never subscribe to any "bundle".  The local cable company that I get high speed internet from keeps trying to sell me their bundle - telephone, TV and internet.  I use  cable for TV (bare bones basic) and internet.  We still have our local landline phone service, and recently changed over to AT&T for cellular service because my wife gets a discount through work.

Each one of those services craps out from time to time.  The landline is most reliable of all,  but it occasionally goes out too.  With a "bundle" you lose everything - TV, internet, phone service, all at once.  I prefer not to put all my chickens in one basket.

Now that we have switched to AT&T mobile phone service, we keep getting propaganda and promotions from AT&T telling us how wonderful their U-verse service is.  At first, I was sort of interested, before hearing about the RFI problem. I checked their website, compared prices, and their "bundle" is only $10/month cheaper than what we now pay for all our diversified services combined.  I have never seen anyone installing fibre optic cable in this area, and the phone lines are underground, so I don't know how they would deliver the signal to this house, but according to their website, U-verse service is available here.

If I start having that kind of interference, I certainly hope the interference is mutual!  If so, I'll make it a point to run my automated CQ all evening long, every evening until I get a readable reply on the radio through the hash. Sounds like this is just as bad as BPL.

I am thinking of going to the local AT&T store and pretend that I am interested, and ask them how they would deliver the signal to my house, and ask them about any possible RFI problem, just to see what kind of bullshit story they tell me.  I'll bring along my little sub-miniature flash memory audio recorder, stick it in my shirt pocket and turn it on to record and document the conversation.

[W1RKW]

Don,
My parents have U-verse and their utilities are underground.  The neighborhood has been there for 40 years and the wiring has never been changed so I don't know how ATT manages to deliver the digital but it works. They have a bundle, phone, TV and internet.  They're happy with it and have never had a problem for a couple of years. 

I don't know about the interference issues but I will now check it out now that Rob/AEX has pointed it out.  I should be interesting.

[WA1LGQ]

Thanks for the video Rob. Its strange, but we cannot get U-verse at my house, but it is in service a couple streets away, about 1/2 mile or so. I will drive through the area tomorrow on the way to the stress club and give a listen to 'TIC and higher. I often do anyway, and have not noticed anything, but will listen more carefully. Could be that I just ignore interference anyway, I'm getting accustomed to hearing it everywhere, all the time. What do you think you would do if it was 1970 and all of a sudden got hit with all the crap in the ether that we have to put up with now??

   

[K1JJ]

Rob,

It would be a good experiment to tune in the 2nd, 3rd and 4th harmonics of 1080 to see what is there. Hopefully the noise harmonics are supressed in the electronics, but ya never know.  If not, this crud could be loud all the way up the various ham bands, considering the broad band wire "antennas" they use. Or, are they pumping thru a 11 mhz wide signal from 1-12mhz? That would be worse.

Sometimes long power line wires become huge gain antennas when they follow a straight street for a mile or so.  I have that problem here occasionally when there is minor noise way down the street. The power lines are a straight shot to my QTH and I get hammered from the SE when it happens.  "Beaming JJ with a CT Light and Power 60hz wire array, caw mawn."

T

[W1AEX]

Ted, (IXY) your comments pretty much sum up the way I feel about this debacle. I did send an email to the station engineer, who is a local ham I have spoken with several times. I expect that he will be quite interested and he is always quite helpful. I have filed a complaint with the F.C.C. but do not expect that much will come of that. The video is mostly intended as a touch point to direct people to, so they can see what I am talking about. I have also contacted the ARRL technical lab for assistance. They have been most helpful in the past, and have even come up here with a very neat portable spectrum analyzer to help pinpoint a blown out lightning arrestor several years ago. They should be able to help me determine which of the 3 services (Power Company, Cox Cable, or ATT) is responsible. The frequency specific nature of the interference leads me to believe that it is ATT, but we shall see.

That road in the video is the only access road available to the 80 families who live in my area at the end of the road. I am not the only one affected by this as they all hear the interference when they drive to the outside world.

Don, (KYV) I had the same reservations about bundled service as you, until I subscribed. The only time all three services went out, it was because some drunk took down a pole. Of course that knocked out power and the ATT phone lines as well as the cable feed. I have to give my local cable company (Cox Communications) a very high grade for their service and reliability. If I have an issue with any one of the services, I am able to talk to a real human within the first 30 seconds of dialing. They run remote diagnostics and can usually fix things right away. If not, they dispatch someone within 24 hours. If any of the 3 services goes completely out, they dispatch someone immediately. The bundle saves me 30 bucks a month, and they renew the bundle deal price every time it expires. Besides, if for some reason all the services go down, I have a cell phone, and can also pick off quite a few OTA stations with my antenna on the tower. So... I would have to say that my initial concerns were completely unfounded. By the way, from what other hams have told me, the interference issue with U-Verse is completely reciprocal. If you transmit between 160 meters - 40 meters, you may blow the whole system offline, even at very low power levels. If you do a search, you will find reports that installers have refused to install the service when they found the potential subscriber was a ham. The U-Verse system was meant to be FTTH or FTTP, which means fiber right to the subscriber's home. Obviously, through smoke and mirrors, they are trying to deliver it on the cheap, over very old copper twisted pair, with predictable results.

Larry (LGQ): It is difficult to determine if this issue is the result of a poor installation process or some equipment failure. Or, it could be the switching supplies they use, or something in each residence that is dirty and pouring back down the drop from the pole. Whatever it is, it is certainly not compliant with Part 15, it is interfering with licensed services, and it is nasty. I'd be interested in what you hear at your location.

Tom (JJ):  ATT utilizes the spectrum from .25 Mhz through 12.0 Mhz to squeeze their FTTN version of ADSL and VDSL (phone/internet/television) services through. The VDSL (U-Verse) service typically carries IPTV (streaming television) and Internet between 1.0 Mhz and 12.0 Mhz. With a small shortwave receiver, I can hear buzzes and oscillations throughout that range while standing about 30 feet away from their lines when I am in that area. Then it seems to fall off fairly quickly. I would imagine that someone who subscribes to the service must have considerable interference to that part of the spectrum within their residence. By the way, Cox Cable uses the spectrum from 5.0 Mhz through 1.0 Ghz to deliver their three services by fiber, hardline, and finally a coax drop to the house and throughout the residence. Think about how compressed things must be on the U-Verse system when compared to the pipe Cox is using. The Cox system is highly resistant to ingress and egress. I don't hear it, and it does not hear me. For me, this issue is simply an annoyance when I drive through that area, and to be honest, like most people here, while driving, I now listen to WHYN at the bottom of the band, which is not affected. I am very grateful that this service is NOT in my neighborhood, where I enjoy fairly noise-free reception.

The website at the link below has some interesting and very revealing information about U-Verse and its issues with RFI:  

http://adslm.dohrenburg.net/vdslm/uverse.php

It looks like ADSLM has an updated page and blog regarding U-Verse at the link below. I'm not sure if the other link is updated anymore.

http://adslm.dohrenburg.net/uverse/index.php

Ah well. It was a nice morning to go for a ride!

[k4kyv]

If they used fibre right to the modem, I might be interested in subscribing. But then, why the 12 mHz limit? Sounds like what they are actually doing is identical to BPL. Fibre to the node, then unshielded copper wire for the "last mile".

It will be interesting when they wire up some neighborhood that has an active QRO ham on 160-80-40.

[W1AEX]

It will be interesting when they wire up some neighborhood that has an active QRO ham on 160-80-40.

Actually, this happened to one of our AM brethren in the southern part of the state. He was bringing his neighbor's U-Verse system to its knees even at power levels well under 100 watts (of AM) on 160 meters. As I understand it, the ATT techs eventually figured out that the RF was coming in over the old CAT 3 wiring inside the subscriber's house, so they filtered it at the point where it intersected the residential gateway and apparently resolved that issue. He did not indicate that the U-Verse system caused him any issues when receiving on the ham bands. In other cases, they were able to resolve ingress by replacing old parallel wire drops from the pole with CAT 6 cable, which has much more immunity to RF. In stubborn cases, they replaced older CAT 3 within subscribers' residences with CAT 6 cable. It appears that rather than installing with RF resistant measures everywhere, they simply do it where an issue comes up.

To be honest, I believe that the problem in that area has something to do with the faulty installation of either powerline hardware or something installed by one of the other companies that run lines on those poles to deliver their services (ATT U-Verse, Cox Cable Communications). It might even be something a subscriber has connected to one of the services. It will be interesting to see what shakes out with this.

[wb6kwt]

Thanks for the video, I had UVerse out to install their system but ran the guy off when he didn't want to run the wiring the way I wanted it.

By-the-way, what kind of mount were you using for your camera? Nice smooth looking video.

Bob

[W2PFY]

This sounds to me to be typical HV static. You said new poles were put up. It's becoming more popular nowadays in some areas to install 34.5 KV lines for distribution. You can usually tell when it's a system using 34.5 KV by looking at the pole pigs. The circuit usually configured in a Wye therefore the transformers are single phase for home service. The transformers have an unusually large bushing coming out of the top (about 10 inches) and in-addition have a large gray thing in series with the transformer bushing to the AC line. I think it may be a fusesistor. When I was in the business of selling large C band satellite dishes, and pointed the dish at a nearby 34.5 KV line, gold speckles appeared on the TV screen indicating some RFI from the line.     JMHO

[WD8BIL]

Hey Rob, you got the same radio in your vehicle as I have.
Great minds think alike!

[W1AEX]

Hi Terry,

Nope, these are buzzy oscillations that appear between 1.0 and 12.0 Mhz and to a somewhat lesser extent below 1.0 Mhz. Unlike powerline noise, it is frequency selective. The local lines are 13.6 KV neighborhood transmission lines. Along that road, if I open the squelch on 6 meter AM, except for one point where an older 13.6 KV line passes over the river into the adjoining town, it is quiet.

Bob (KWT) Thanks for the video production comment! One of my neighbors gave me his old lightweight aluminum camera tripod when he bought a new one. What I did was put 2 legs on the floor in front of the rear seat, and then put the third leg on the back seat. I extended that third leg so that the tripod pressed firmly against the front seats and it made a very stable platform. The camera produced a 600 meg AVI file, which I compressed using the free XVID codec with the free VirtualDub software (I love free stuff) to produce a video roughly 40 meg in size. After uploading it to YouTube, they processed it to their format and the resulting video appeared on my page.

Buddly (BIL) Isn't that a great radio? After my son got one, I had to grab one too. Really nice AM/FM receiver, front panel input jack, and it plays MP3 files burned onto CD media. Nice! Definitely great minds at work there!

I have received very encouraging responses from WTIC and the ARRL. They are very interested...

[ka3zlr]

Howdy,

 We have digital HD Dish and I pulled all the wire put in by cable an Burnt it,,,an all of a sudden no problems...yea..

73

Jack

[w1vtp]

Rob

I've been plagued with what sounds like raw AC junk that appears on the 75m band.  Very frequency specific.  Next time I hear or see it I'll take a screen shot of it on the Flex.  It will change frequency much like the old buzz of B&W TV sets would as the picture changed.  I'll put it up next time I get a chance

Al

[W1AEX]

Al,

I drove over to a relative's residence that is along the path that I drove in the video. She is in the area where U-Verse is deployed, but is not a subscriber. What I found was interesting, and corresponds to what you are hearing as well. I heard several buzzy oscillations randomly spaced in the bottom half of the broadcast band with a sharp rise in noise above 1.0 MHz. I could detect the noise up as high as the 20 meter band. Some frequencies in the broadcast band have no interference while others are obliterated. The oscillations may extend down into the LF and VLF regions, but the SW receiver I was using did not hear much down there.

The oscillations sound an awful lot like the video synch buzz that is radiated by CRT television sets. However, these oscillations don't wander, they stay where they are. I listened to an AM QSO on 3885 for a few minutes, someone running a Collins 32V transmitter (this was around 4:30pm today) had a very strapping signal. Unfortunately, one of the oscillations appears to sit close to 3885 and it was fairly prominent while standing in the front yard, 30 feet from the street. The interference could still be faintly detected with my portable at a distance of 100 feet. I suspect that the typical ham antenna used on 160m - 20m would pick up a fair amount of noise depending on how close to the delivery wiring it is installed.  

Another thing I noticed while driving, is that the peaks in the noise seemed to correspond to the wire drops from the poles to various residences. As you pass under them, the noise becomes very intense. Curiously, this only happened while driving by random houses, not all houses. That makes me wonder if you hear the loudest noise as you pass under a drop going into a subscriber's house, which leads me to wonder if the noise is actually generated by some equipment that is installed inside a subscriber's house.

At any rate, today's little experiment made me grateful for the blissful quiet I have in my own area. I hope it continues...

Have you determined the source of the synch buzz noise you are hearing Al?

Jack (ZLR) I am a big fan of cable. It does not bother my equipment, and my equipment doesn't bother it, and I have not had an interference complaint from anyone in the area for over 25 years. I would like for it to be cheaper, but I will pay for services that are reliable and that deliver what is promised. I have noticed quite a few small satellite dishes sprouting up in the area over the past 10 years. People seem to like what they are getting with that service as well. Again, it seems to be an agreeable technology that does not interfere and also resists interference, so it's welcome here!

[ka3zlr]

Hi Rob,

 Same here in the beginning, then as the years went by things got junky
they kept taking away stations an increasing the bill noisy broadband amps
a few lightening strikes bad service ....i've had enough...

No problems A toll with Direct TV.....  

73

Jack.

[k4kyv]

A question I have is why is U verse so much worse than ordinary DSL?  They both work on the same principle, brute-forcing digital data through copper telephone pairs.  I opted for cable internet service for that very reason, but have never heard of any complaints about RF issues with ordinary DSL.

The only difference I can think of, and perhaps I am answering my own question, is that DSL streams data only for internet service, while U verse is trying to simultaneously provide high speed internet service, telephone service, and hundreds of TV channels, many in HD.  This would necessarily require shoving far more spectrum bandwidth through the unshielded twisted pair that was designed only to deliver analogue audio, or at most, multiplexed SSB channels from about 64 to 108 kHz.

[W1AEX]

Well...

As it turns out Don, in this case, it might not be U-Verse. The local AM station's engineer, and a representative from the IEEE, along with a lab engineer from the ARRL came out and spent an afternoon with some gear to track it down. Several findings were interesting:

1. The noise "appears" to be gap noise, and they were able find several "hotspots" along that road.

2. Oddly, it is frequency selective rather than just being the expected and more typical broadband hash. There is a major collection of buzzy oscillations from 1.0 MHz to 1.4 MHz, but the instances of oscillations drop off sharply on either side of that range.

3. Additionally, there are frequencies between 1.0 MHz and 1.4 MHz that experience no interference, while others are obliterated. Also, there are random buzzy oscillations that appear below 1.0 MHz and also appear up as high as the 20 meter band.

4. The noise content does not appear to be data noise, which means that it is NOT the streaming data that U-Verse is sending along those lines.

5. The noise propagates along the lines of that road, but does not propagate into adjoining neighborhoods. This suggests that the noise is not on the 13.6 KV primary lines.

6. Normally, as I drive along a road that has powerline noise, I can hear it loudly on 6 meter AM with my mobile rig. That is not the case here. I can cruise that road with the squelch open and hear some growling here and there, but nothing that corresponds in any way to the noise on the broadcast band that is cleaning out the 50,000 watt local station.

This could be a single point failure of something a subscriber has installed within their residence. It might have been installed improperly, or something might have failed. There have been reported instances of Direct TV receivers experiencing a kind of failure that backfeeds into the telephone lines and propagates loudly for thousands of feet. There are quite a few Direct TV antennas visible along the noisiest section of that road by the way.

So... at this point, the local power company has been contacted and they are scheduled to come out this week to probe around for blown grounds, lightning arrestors, or other hardware failures. If they find nothing wrong with their lines (which were completely rebuilt in 2007) then it should get very interesting. All bets are off then. It could be ATT, Direct TV, cable company equipment, or some third party equipment installed by a subscriber in their residence. It is my understanding that the power company will attempt to determine which residence is the source of the noise in cases where they find it propagating from a specific drop. However, the power company has no responsibility for the issue if the problematic equipment connected to their lines is not theirs.

On a humorous note, I received a reply from the F.C.C. to the complaint I filed. It informed me that they were not responsible for interference to consumer receivers and suggested that I work harder to improve my reception...

I filed a second complaint and sent copies to all the commissioners instead of just to the narrow group that handles consumer complaints. At the time I sent it, it appeared that ATT was still the guilty party. The text of my letter is below the dotted line. No response yet from anyone except the original responder, who informed me that they had mailed something to me on the 20th...

-----------------------------------------------------
Subject:  Unsatisfactory Response to Interference Issue

Dear Commissioners,

I recently filed an online complaint (Reference Number:  10-C00211501) through the FCC website regarding interference to a wide swath of frequencies from the bottom of the AM broadcast band through 40 meters, from equipment installed by ATT as they deployed their FTTN U-Verse system in my town of East Granby, CT. The anonymous email reply that I received from the FCC would lead me to believe that either it was an automated, scripted response, or the responding staff member did not read my complaint, or they did not understand the issue. Since the interference is caused by widespread, loud, buzzing oscillations between 500 kc and 12.0 Mhz, covering an area in excess of a mile, this is not a problem that I can resolve by improving my reception capabilities. This is a case of interference to a number of licensed broadcasters as a result of the improper installation of equipment or the failure of a device(s) installed by ATT as they deployed their FTTN U-Verse system, which utilizes the frequencies between 25kc and 12.0 Mhz.

I have contacted ATT twice in an attempt to ask them to investigate this issue, but they have emphatically refused to look into it. Again, there is nothing that I can do personally to resolve this interference since it can only be corrected at the source. At this point, I would simply ask where I should direct my concerns for the best chance of getting this resolved?

For a quick look at what the residents out here are experiencing, feel free to view a short 2 minute video showing the effects of the interference on a nearby 50,000 watt broadcast station, WTIC, located in Hartford, CT. Please note that these strong oscillations can also be heard loudly on the 160 meter/ 75 meter/ 60 meter/ 40 meter amateur radio bands:

http://www.youtube.com/watch?v=bKs8I-bPyRM

Pasted below are my observations regarding the interference, and the corresponding response I received from the FCC. Again, there really is no way for me to investigate the source of this issue since I have no authority to inspect equipment installed by ATT or any other utility that distributes its services in this area. It could simply be a single point failure that is causing the widespread disruption.

I look forward to hearing from you regarding this situation in the hope that you can direct me to the appropriate agency, division, or bureau, who can make a phone call, send a letter, or motivate the source of this interference to correct it.

Respectfully,

----------------------------------------------------------

[WA1LGQ]

Rob, I have driven through the area that I mentioned a number of times and heard nothing like what you heard. There was some digital sounding junk on 1100 in a very small section of the area, but it was not there every time I drove by. Recently though I tracked down a source of an odd pulsating-arcing noise that was bothering my 80/75 M reception in the daytime. The source was in that same area which is about 3/4 mile from me. It was a case of wideband noise that was audible at higher and higher freqs as you get closer to the source. I used a directional ant on the aircraft band and narrowed it down to the vicinity of a power pole with a transformer on it. But I could not really pinpoint the source as the lines or the transformer. It seemed to be coming from a house there possibly. So I contacted the power company via email and telephone. I said that I was not really sure that the noise was coming from their equipment, but please check it out. The noise did not really act like a gap noise, it was a pretty consistent thing, not affected by weather very much if at all.  Eventually they came out and it turned out to be something in one of the houses. The power company just went to the door and told the owner that there was something arcing and could be a fire hazard. It was not their responsibility to fix whatever it was. Bottom line the noise went away happily for me and maybe for the owner. They told me that the owner stated that they were having trouble with their AM broadcast reception!

..........LB.......

[W1AEX]

Larry, that's an interesting incident, and a good result for you! One thing is for sure, these issues will not go away by themselves. Nice job of narrowing it down and getting the power company involved. The question that lingers in my mind is what if the owner of the equipment decided not to power it down? There really is no apparent enforcement in this area when it is a simple consumer complaint.

Part of the discussion with the group that is investigating the noise in my town was that the NAB is getting very concerned. The station owners invest money in equipment, pay out money for content to broadcast, then attempt to sell their coverage to various advertisers, only to have their signal crushed by some $29 miracle technology from China that is sitting on the shelves at Walmart. The average consumer who is affected by interference really has no one to call. What they are doing is simply turning their radios off. At this time, and probably forever, the FCC appears to be insulated from and unresponsive to consumer complaints. It's not surprising that the listening audience on the AM broadcast band is shrinking at a very quick pace as the noise grows. The NAB would like to see an enforcement mechanism instituted that would give them some protection. Of course, that would be very good for us as well.

Just when you think it is bad enough with mini-wall-wart switching supplies, big sales on plasma televisions, LED traffic lights that obliterate VHF, and the usual powerline events, you find out that Netgear and Belkin are introducing and pushing very hard a new product line for home networking that magically turns every outlet in your house into an ethernet port. It utilizes the entire HF spectrum and continues right up through 300 MHz! Perfect for streaming video and data anywhere throughout your house! Easily detected by a portable shortwave receiver or a scanner from hundreds of feet away! Who do you call when your neighbor plugs this into their house electrical system?

I continue to count my blessings that I live in a quiet area right now. But all it takes is one neighbor within a quarter mile to buy some idiotic technology that will change that in a heartbeat.

[flintstone mop]

Two short RFI stories:
A charger for an FRS radio was across the street from a Mercer County 911 center and wiped out all of their commo. The local two-way shop that provided service could not find the problem. The FECES found it with some good snooping hardware.
Things were getting critical and close to a melt down with an entire 911 center off-line.

A local fire department had their commo knocked out by a pre-amp connected to a UHF TV antenna. The two-way shop I work for found the problem with a spectrum analyzer on battery power. Driving in the owner's yard showed one helluva signal in the 450 band and we asked the owner to start turning off stuff.


I'll have to read more about U-verse. Anything like BPL or is it along the lines of a super DSL on a CAT 6 cable radiating everywhere?
Fred

[W1AEX]

I'll have to read more about U-verse. Anything like BPL or is it along the lines of a super DSL on a CAT 6 cable radiating everywhere?
Fred

Actually Fred, most of the complaints regarding ATT and its U-Verse system's utilization of 25 KHz - 12.5 MHz over unshielded twisted pair are from issues where nearby transmitters severely disrupt their data stream. Apparently, it doesn't pose a serious issue to nearby HF receivers when it is installed correctly. It looks like my accusing tone towards U-Verse for the issue across town from me may have been misguided, but only time will tell as the investigation gets closer to the source. It has been brought to my attention that subscriber equipment connected to a U-Verse system, or even a satellite installation, can cause widespread RF interference.

Interesting RFI stories. Fortunately for all of us, it appears that things get resolved quickly when public service communications are disrupted. It's amazing how much trouble can be caused inadvertently by some of the appliances on the shelves of Walmart!

[k4kyv]

Back in the days when medium wave AM was king of broadcast  radio, this shit wouldn't be happening.  The public would not have tolerated trashing the broadcast band.  That kept the power company and manufacturers of electronic and electrical gadgets on their toes to avoid interference.  But these days, very few people listen to AM broadcast radio.  Most radio listening is to FM, and that is done 99% in cars. So the polluters can fry and buzz away and nobody even knows, let alone cares.

A little over a year ago I had a severe power line noise problem.  I was able to sniff out the source to a spot about 2 miles from here, but could not pinpoint exactly which pole.  I went to the area, carrying a portable AM/SW receiver on foot, and began knocking on doors.  I found about a half dozen people home.  I asked them if they had been having any problems with radio or TV reception, and gave them a demonstration by playing the radio. Every single one of them was completely unaware of the problem, even though they were living right under the source.  They all got their TV from cable, and listened only to FM radio, only in their cars.  The local AM station is located about 8 miles away but was marginal at best due to the interference.  None of the people I contacted had a clue anything out of the ordinary was going on.