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Verizon LTE Interfering With Time Warner Cable TV in Raleigh
by Karl Bode 09:24AM Wednesday Dec 04 2013
An anon user submits this story by local Raleigh outlet WRAL claiming that interference between Time Warner Cable and Verizon LTE services is causing video issues for many Time Warner Cable customers. The culprit, according to the report, is Time Warner Cable's channel placement, unclicensed use of the spectrum, and unshielded hardware, which are now colliding with Verizon's new use of 700 MHz in the triangle area. "We apologize for the inconvenience and are working on a solution that will resolve this problem definitively in the coming weeks," Time Warner said in a statement, though the company stated it would take time to migrate the channels off of 700 MHz to eliminate the interference.

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RWSI

join:2012-11-27
Albuquerque, NM

Interference

It's about time. Interference on cable TV is nothing new but the issues are from some source at a distance form the end user. Nearby FM stations to the end user always causing problems in a system I worked for and could not be resolved. It was though unused on the cable system because of nearby broadcasters. Now high power cell sites are deployed right in the middle of the cable systems and will never be resolved because the licensed LTE has primary usage rights. Eventually
this will happen all through out the USA and other places that have old style coax networks. Deploy an LTE cell next to the headend of the cable system and the spectrum over coax will never be able to be used again.
On the reverse of the coax I proved that just a CB radio could overwhelm the below 54MHz return and overload the amplifier making it useless. Imagine a high power Ham radio and the damage it could do.
guppy_fish
Premium
join:2003-12-09
Lakeland, FL
kudos:1
Reviews:
·Verizon FiOS

1 recommendation

Re: Interference

said by RWSI:

will never be resolved because the licensed LTE has primary usage rights.

LTE is the ONLY licensed, not primary licensed user of the spectrum

Old crappy cable needs to clean up its act, using 30 year old coax is the issue here, but TW won't do a thing as there looking to be sold
InvalidError

join:2008-02-03
kudos:5

Re: Interference

said by guppy_fish:

but TW won't do a thing as there looking to be sold

Having part of their cable network shut down by the FCC with associated fines and damages due to leaking all over Verizon's and other licensees' spectrum or otherwise reserved bands is not going to look good for potential buyers either.

So they either have to start repairing now to raise the company's valuation and reduce their liabilities or get devalued by some amount based on the estimated repair costs and risks. I doubt they can wiggle themselves out of this one either way.
TBBroadband

join:2012-10-26
Fremont, OH

Re: Interference

And you forget the FAA when it starts to leak into the aviation areas of spectrum. I would like to see TWC fight the FAA over the controls on a plane or their control towers acting up due to their mismanagement.
InvalidError

join:2008-02-03
kudos:5

Re: Interference

I think the FAA, emergency services and everything else that isn't Verizon was covered under "other licensees or otherwise reserved bands"

If cable egress was bad enough to mess with airports and airplanes, I think the FAA would have complained to the FCC a long time ago. Since airport antennas are aimed at the skyline, most of the ground/pole-level wiring and leakage likely ends up below their horizon line.

Also, aren't there clauses in cablecos' operating licenses that forbid them from using some critical bands like those reserved for emergency services exactly for the purpose of eliminating the possibility of cable egress interfering with those frequencies?
cramer
Premium
join:2007-04-10
Raleigh, NC
kudos:8
You've got it backwards. TWC is the one eating the interference. TWC isn't causing a problem with Verizon's LTE, so there's nothing to be fined over.
InvalidError

join:2008-02-03
kudos:5

Re: Interference

I'm not getting it backwards: if TWC is complaining that Verizon signal is getting into their coax then it means TWC is using those frequencies for something or they wouldn't care much about it unless their outside plant is in such a bad shape that ingress Verizon signal is causing in-line amplifiers to start clipping or something. (Still TWC's problem either way.)

Now, if signal can get in, it means the signal can also get out - an antenna is every bit as efficient at receiving signals as it is at transmitting them. If TWC is having trouble with Verizon signals getting into their improperly shielded old wiring then TWC's signals across the same band are likely causing some problems to people passing by the more leaky areas of TWC's coax plant.

Verizon is the only one licensed to use that spectrum over-the-air in the area in question so if TWC wants to use that spectrum on their coax, it is entirely TWC's responsibility to ensure that both ingress and egress on those licensed frequencies across the whole affected area are within tolerances.
cramer
Premium
join:2007-04-10
Raleigh, NC
kudos:8

Re: Interference

The problem isn't (apparently) Verizon's broadcasts (from towers) getting into the coax cable plant; it's that local sources (read: your shiny new iPhone) is a stronger signal than what's on the cable at the cable box. TWC can complain all they want; they are the one's at fault, and per FCC rules, must accept the interference from the licensed user of the spectrum. (read: twc needs to shield their boxes better, or, as they're planning, don't use those frequencies.) The FCC testing procedures only look at how much and at what frequencies a device emits RF; they don't give a shit if someone else's signal can get in and cause malfunctions.

quetwo
That VoIP Guy
Premium
join:2004-09-04
East Lansing, MI

4 recommendations

Looks like TW needs to fix their cable system...

If they are getting ingress interference, then they are also leaking RF like mad too. And if they are leaking RF, then I'm sure the FCC will be paying them a visit soon... Verizon is completely in the clear on this one -- TW's closed system shouldn't be taking in any interference and shouldn't be causing any...
cramer
Premium
join:2007-04-10
Raleigh, NC
kudos:8

Re: Looks like TW needs to fix their cable system...

Their signal is FAR too weak to do anything mere feet away from the cable. It's not a radio station; it's a captive system (or it's supposed to be.)
guppy_fish
Premium
join:2003-12-09
Lakeland, FL
kudos:1
Reviews:
·Verizon FiOS

LTE is licensed for the spectrum

The issue is cable, not wireless operators.

Cable is NOT licensed for the spectrum it uses, which is suppose to be in shielded cables, if cable is getting egress, that's Time Warners issue to fix, which is decades old coax needing replacement.
cramer
Premium
join:2007-04-10
Raleigh, NC
kudos:8

Re: LTE is licensed for the spectrum

Actually, it's the ingress of a licensed user that's the problem. TWC's "fix" is to just stop using those channels instead of patching their not-so-sealed system.

SATech

@rr.com

It's a Headend issue

If this is all over the place, it's not coax, this is going to be a tower near a HE which is not shield at all...

RWild
Them Or Us
Premium
join:2003-09-15
Cary, NC

1 edit

Re: It's a Headend issue

I have this issue. When a phone or tablet of a Verizon wireless customer sends a signal using LTE, it causes interference for a particular channel (the one TWC uses for WRAL). The frequency (700 MHz I think) is licensed to Verizon and should not be used by TWC. Don't think it has anything to due with whether TWC has crappy coax.
Kalmus

join:2012-11-21
Boston, MA
It doesn't appear to be the HE. According to the WRAL.com article, the interference only occurs when a 4G LTE device and a cable box are in the same room.

telcodad

join:2011-09-16
Lincroft, NJ
kudos:5

Re: It's a Headend issue

said by Kalmus:

It doesn't appear to be the HE. According to the WRAL.com article, the interference only occurs when a 4G LTE device and a cable box are in the same room.

Yes, it's a cable box shielding issue. There is a blog item about it with more detail on the Capitol Broadcasting corporate website:

4G lte + Cable = 1 BIG Problem
By Sam Matheny, Capitol Broadcasting VP Policy and Innovation, CBC View blog - November 7, 2013
»www.cbcview.com/2013/11/4g-lte-c···problem/
F100

join:2013-01-15
Durham, NC

1 edit

Re: It's a Headend issue

It's not just a cable box issue. I have had the problem also but I am using a tuner card and an HD Home Run network tuner to record in media center via clear QAM. No cable box. All of my coax is properly shielded and grounded. Distribution coax lines run underground in my neighborhood. Don't laugh but I still only have an old Verizon flip phone that I use for CDMA voice only. That is 800Mhz/1900Mhx bands I think. We don't have any LTE phones yet. My neighbors do though. WRAL shows CBS programming and I noticed it while watching a recording of "How I Met Your Mother."

I comes across as breakup from a weak signal. TWC has WRAL on QAM cable channel 121-2 as shown by the HD home run tuner setup. They are getting ingress into the plant somewhere from Verizon's 700mhz frequencies when they are trying to use the same frequency range in a closed plant system. I am getting it too so it's not just a cable box issue. It's further up in the coax plant.

I suspect their fix is to move WRAL to another channel on the cable system. WRAL also owns WRAZ Fox 50 that is on QAM channel 121-5.

Edit: I don't have a turner card, just a PC card with a Clear QAM tuner and an HD home run with only Clear QAM and ATSC tuner. All coax is directly connected and unused ports have terminators on them.

telcodad

join:2011-09-16
Lincroft, NJ
kudos:5
An article with some more details on the DailyTech site today:

Time Warner Cable Experiences Verizon LTE Interference in N.C.
By Jason Mick, DailyTech - December 5, 2013
»www.dailytech.com/Time+Warner+Ca···3876.htm
F100

join:2013-01-15
Durham, NC

Re: It's a Headend issue

Kudos to telcodad who let me know that my post was quoted in this article. Paragraph 2 under Section I. Interference Woes reads very similar to my second quote. I just searched for the frequency info and found most of it on Wikipedia anyway. Jason Mick must keep up with DSLR. Since he quoted my comment with a link to this forum on DSLR, I'll have to give him a thumbs up too. It was a well written article.

WRAL air a story about this issue on Tuesday's 6pm new broadcast. Karl posted it here on Wednesday. Capitol Broadcasting Company (CBC) is the parent company of WRAL, WRAZ. Jim Goodman and family own CBC, the Durham Bulls Baseball team and real estate like the American Tobacco Campus in Durham. They are pretty big players in the Raleigh, Durham, Chapel Hill area.

CBC has been on the forefront of broadcast technologies like HDTV and ATSC digital TV. They were using full HDTV way before most. That's why it's ironic that CBC stations are the ones have this issue with TWC. CBC has known about this for months. Now the problems is getting worse and TWC is taking its time to rearrange the channel lineup, so CBC is using their power to let people know who is really responsible for fixing the interference.

dandeman
Premium,MVM
join:2001-12-05
Chapel Hill, NC
Reviews:
·AT&T Southeast

4 edits

Cable systems leaking into frequencies authorized for ham radio use

One of our ham radio club's repeaters, FCC licensed of course, uses 145.230mhz.. and in riding around the area, you hear various locations where the system is leaking cable channel 18 video nearly on top (145.250mhz) of that same frequency, which they use to carry one of the local TV channels...

Some years back we worked with the cable company to find the source of leaks in one apartment complex. They were interested in so doing as they held the view that a number of the leaks typically come from illegal taps into the cable system. Also the fact, that they can be fined by the FCC for such leaks... but given the cable strung all over the country that's a near impossible task to monitor, even if the FCC made the effort to do so. I understood at the time that the FCC did make occasional aircraft flyovers as a way to find leaking systems.

But it's seems similar to the situation of trying to plug numerous leaks in an old dam about to burst.. and I would suspect even the in-house set top box to TV wiring quality is part of the problem.

Agree the old cable system needs a major new architecture upgrade (fiber?) to replace the current commonly leaking cable system, spilling into frequencies licensed to others.
--
To be persuasive we must be believable; to be believable we must be credible; to be credible we must be truthful. -- Edward R. Murrow

»home.4x4wire.com/deddleman/

IowaCowboy
Iowa native
Premium
join:2010-10-16
Springfield, MA
Reviews:
·Verizon Broadban..
·Comcast

1 edit

1 recommendation

It's an ingress issue

Sounds like a signal leakage/ingress issue with the cable plant that TWC needs to fix. Can be anything from an open connection to a squirrel chewed wire. It's going to be a game of cat and mouse for TWC.

A few years back we had an ingress issue on our node that was a real headache for Comcast to troubleshoot.

VZ is in the right here, TWC needs to find the ingress point and fix it.

Maybe the homes themselves have faulty wiring or older RG59 cabling. I never leave open cable outlets in the house, I always terminate them with a cable terminator.

--
I've experienced ImOn (when they were McLeod USA), Mediacom, Comcast, and Time Warner and I currently have DirecTV. They are much better than broadcast TV.

I have not and will not cut the cord.
Technicholas

join:2010-11-11
Winterset, IA

This happens also in other markets

My friend also had this issue in the Ohio market we did not make the two together that his phone was causing this he is nolonger a timewarner tv subscriber he switched to AT&T uverse.
brad152

join:2006-07-27
Phoenix, AZ
Reviews:
·CenturyLink

Re: This happens also in other markets

If your talking about Columbus, that market has probably some of the worst wiring of any TWC market in my experience.

I've lived in just about every part of Columbus proper and the 'burbs and TWC always has gotten a lot of interference since they never really bothered to fix the old aging 70's style system. The ingress was so bad from the local stations 4,6,10 that they had to put them on different channel numbers and put things like the the channel guide that people never really used to get around it.

That was by far the worst cable system i'd ever used, and all they do now is try to run everything duplicated on SDV so people with boxes do not notice it.

I was truely upset when they took out Insight, as that was by far the most reliable cable system i'd used (sure it was old, but no ingress nor did they ever deploy SDV - made having a TiVo easier and not to mention no random SDV drops like on Cox and TWC)
Technicholas

join:2010-11-11
Winterset, IA

Re: This happens also in other markets

Dayton market
F100

join:2013-01-15
Durham, NC

See the overlap

So it appears that according to EIA standard 542-B, the North American TV band has channel 121 as follows: Video Carrier (MHz) 775.25, QAM Carrier (MHz) 777.00, Audio Carrier (MHz) 779.75

Verizon's LTE deployment on 700MHz is: Block C: 22 MHz bandwidth (746–757 and 776–787 MHz).

It's pretty obvious the frequency overlap is bleeding into TWC's system. As I posted above. I'm seeing it on a Clear QAM tuner and I don't even have an LTE phone nor a cable box. I'm getting it from elsewhere in the plant. Neighbors perhaps? Maybe. Wherever it comes from it is impacting other users in the system. Turing on Airplane mode or moving to another room is just advice to placate complainers that blame WRAL. TWC will have to move the stations to another channel in the system which will me that I have to remap media center all over again. Not fun but better than watching a show that freezes up every few seconds.
Jazzemt

join:2009-02-12
USA

Ingress

The issue is that the cable companies are looking for leakage only in the VHF air band and not in the LTE band. In my local area Sprint is identifying leakage that the techs are amazed that they do not see on their VHF gear. And the higher the frequency the easier for ingress and egress to use a smaller hole that lets little VHF pass.

koolman2
Premium
join:2002-10-01
Anchorage, AK

Unused outlets

Some of the ingress may be partially caused by unused outlets. I've long wondered why cable companies don't give terminators to customers to put on an outlet if they move equipment around.
F100

join:2013-01-15
Durham, NC

Re: Unused outlets

Right koolman2. All my coax is RG6, some quad shield, either pre-made or terminated to spec. I did add an 8 port drop amp at at the PC so I could split the signal for all the tuners. All unused port on the amp and elsewhere in my house have terminators. Bought a bag of 10 from Amazon when I bought the amp. Already had a few lying around. Installed all but one piece of coax myself.

My system is grounded at NID. Also ground the outdoor antenna there too. Antenna is all on separate coax. I'd say there is very little chance of ingress in my system, unless it is though the equipment like the tuners or TV. I wish I had an LTE device to see if I could even cause the signal to breakup. I'll have to ask my neighbors who have Verizon LTE to see if they have noticed a problem. They are on the same trunk line, just further up for their drop.
megarock

join:2001-06-28
Catawissa, MO
Reviews:
·Charter

I have to ask...

Who the heck writes the titles for these articles??

"Verizon LTE Interfering With Time Warner Cable TV in Raleigh"

"The culprit, according to the report, is Time Warner Cable's channel placement, unclicensed use of the spectrum, and unshielded hardware"

Seems to me Verizon LTE has nothing to do with it. The problem is Time Warner - 100%

Here is your new title:

Time Warner's Unlicensed Spectrum And Faulty Equipment Causes Customer Headaches.
MrBungle87

join:2013-01-18
Durham, NC

Is this affecting Internet service?

In areas where TWC hasn't upgraded their plant (I think Raleigh is still on 750MHz or something) would ingress also affect Internet in addition to TV? Or not so much?
F100

join:2013-01-15
Durham, NC

Re: Is this affecting Internet service?

This Verizon ingress shouldn't as it's in a different part of the spectrum. My 4 downstream modem channels range from 603-621MHz. See forum »TWC Raleigh (Wake Forest) now bonding 6 channels for a picture.

The upstream signal to TWC is on low frequency, say around 37MHz. Usually between 5MHz to 42MHz.

The construction of Coax is designed to keep signals from bleeding in or leaking out. But if something close enough and strong enough is using the same frequency, it can cause issues if the shielding is not sufficient. Look inside a wireless router or Access point and you will usually see RF cans over the radio chips that send and receive the signal.