iPhone Causes HD Picture Loss

[bobkbusch]

Please forgive me if this has been answered already. I've searched the forum and read discussions about similar issues, but haven't found an answer.

I just finally figured out that my family's GSM phones (we switched to AT&T in January) are interfering with Comcast HD cable reception on our three Tivos (two S3 and one TivoHD).

Whenever the phone makes/receives a call, the picture tears/freezes/macroblocks...

I went to the DVR Diagnostics page on my Tivo and watched the signal strength as my wife made a call with her iPhone. Signal strength dropped from 85 to 0.

I'm pretty sure the cable is RG6. I'm a bit confused by this article here... (can't post a URL yet, so substitute . for DOT)

abccablesDOTcom/info-rg59-vs-rg6.html

Should I have my cable company swap my cable to RG59? Are there any other filters or solutions available? Anyone want to buy a couple of iPhones? :)

[TexasGrillChef]

I have AT&T phones as well. Not iPhones, but all have been PDA phones of some sort.
I have had all brands from samsung, HTC, Blackberry, HP, and even pantech.

While mine don't cause issues with my TiVo's, they do cause issues with ANY of my SPEAKERS in the house. If someone is using the phone within about 12 feet of ANY speaker, you hear a small buzzing comeing from it. It's even worse if the speaker is an amplified speaker and they are turned on. (Such as most computer speakers).


I even have BARE raw speakers... non powered.... if I come within about 6" of those, even they start buzzing! HAppens with ANY AT&T phone! Even my next door neighbors and my mom's! They dont' even have a PDA phone either.

I think it has something to do with AT&T and the fact that I am about 100 yards from High Voltage powerlines. They are the ones coming directly from the powerplant. I think they are teh 250,000 volt ones.

I go to my mom's house (In Oklahoma city) and neither her phone, nor mine, or my wife's have any problems around speakers at her house. But she lives out in far far north side of OKC in the country too. (Still with in city limits, go figure).

TGC

P.S..... I would recommend having RG59 or even better coax installed. Filters won't do much good. What you need is cable with good sheilding and then well GROUNDED! Have them put in grounding block with 12 gauge or better copper wire connected to a COPPER grounding stake that goes into the ground at least 4 feet. My RG59 is grounded with a grounding block and grounded to 4 foot grounding rod as well.

[netringer]

Any GSM phone will SCREAM a strong transmitted signal tot he network if it thinks it's getting out of range. You can get interference on even close by wired phones and as above, speakers. Just moving the phone an arm length away can stop the noise.

It still shouldn't hurt your cable signal if the phone isn't right on the Tivo. I charge my iPhone only 6 feet away from the TiVo and don't see a problem with reception i could correlate.

I'd call Comcast and have them check the cable connections for integrity.

[hillstones]

Please forgive me if this has been answered already. I've searched the forum and read discussions about similar issues, but haven't found an answer.

I just finally figured out that my family's GSM phones (we switched to AT&T in January) are interfering with Comcast HD cable reception on our three Tivos (two S3 and one TivoHD).

Whenever the phone makes/receives a call, the picture tears/freezes/macroblocks...

I went to the DVR Diagnostics page on my Tivo and watched the signal strength as my wife made a call with her iPhone. Signal strength dropped from 85 to 0.

I'm pretty sure the cable is RG6. I'm a bit confused by this article here... (can't post a URL yet, so substitute . for DOT)

abccablesDOTcom/info-rg59-vs-rg6.html

Should I have my cable company swap my cable to RG59? Are there any other filters or solutions available? Anyone want to buy a couple of iPhones? :)

I have two iPhones in the house. Time Warner Cable in LA. No interference at all, even when the iPhones try and search for a signal.

[teasip]

I have noticed that when at work that if I have my iPhone near my computer with our VOIP system that I will get static sound from the computer.

[bobkbusch]

Yes, I've noticed speaker interference as well. If we don't put our iPhones in "airplane" mode and leave them in the bedroom, the clock radio speaker will randomly buzz and wake us. BTW, I'm an airline pilot and I've heard the exact same "buzz" in my headset on final approach. Now you know why we ask you to turn off your cell phones!

Even when my wife was outside last night, two walls and a floor away from one of our S3 Tivo's, it cause enough interference to pixelate/macroblock/tear/freeze, or whatever you call it...

My sons have different AT&T phones and they cause the same problem.

I'll be calling Comcast to have them come investigate. Again, it is only the HD channels that are affected.

[Mars Rocket]

While mine don't cause issues with my TiVo's, they do cause issues with ANY of my SPEAKERS in the house. If someone is using the phone within about 12 feet of ANY speaker, you hear a small buzzing comeing from it. It's even worse if the speaker is an amplified speaker and they are turned on. (Such as most computer speakers).

That happens with every iPhone I've ever seen. It has nothing to do with proximity to AT&T towers; the iPhones are just poorly shielded I suppose.

[Dennis Wilkinson]

That happens with every iPhone I've ever seen. It has nothing to do with proximity to AT&T towers; the iPhones are just poorly shielded I suppose.

Of course they're poorly shielded; they're transmitters.

Every GSM phone I've ever used, iPhone or not, induces buzz in poorly shielded speakers.

[rvsj]

Should I have my cable company swap my cable to RG59? Are there any other filters or solutions available? Anyone want to buy a couple of iPhones? :)
RG59 is not what you want. The general practice today is to remove RG59 and put it in a trash can where it belongs. You need RG6 quad shield cable to keep the signal from the iphone from getting into the cable system. Even that won't work if there are any problems in the grounding system. The most likely cause is an improperly installed connector on the end of a cable or a connector outside in the elements that isn't rated for outside installation which can lead to corrosion.

[hillstones]

That happens with every iPhone I've ever seen. It has nothing to do with proximity to AT&T towers; the iPhones are just poorly shielded I suppose.

It happens with many cell phones that are GSM based. My Moto Razr with AT&T did it, as well as my iPhone. However, my phone would have to be within a foot of a computer speaker or phone for me to hear the interference when it searches for the nearest tower. As Dennis said, if a phone were shielded, they wouldn't work.

I can leave my iPhone on my coffee table with no interference heard through speakers, and no interference to TiVo.

[bobkbusch]

Here is part of the article I referenced above...

------

...RG6 Dual and Quad Shield don't have the proper type of shielding for the above described applications. It is manufactured using foil shields and braided aluminum shields. The makeup of the shields differs between models. The effective range of operation for foil shields is above 50MHz, which makes them perfect for rejection of radio frequency interference, or RFI, that may have an effect on satellite or cable installations. At frequencies below 50 MHz, however, foil shields are not effective. The braiding on the RG6 Dual shield and the RG6 Quad shield doesn't have enough coverage to work effectively with baseband applications.

The frequencies that are used in High Definition are usually around 37 MHz. For those lower frequencies, an RG59 with an 95% copper all-copper shield is designed to block RFI inclusion at base band frequencies.

------

Im so confused....... :o Part of what confuses me is the description about High Definition frequencies in the 37 MHz range and RG6 shielding not effective below 50 MHz. Does this apply to cable systems such as Comcast? I don't think GSM transmits/receives anywhere near this range.

Since my problem only exists with the HD channels, I'm wondering if this has anything to do with it. The article also clearly states that RG6 is much more preferable for satellite and cable systems as is noted in some of the above posts as well. I want to be armed with as much information as possible when the cable guy shows, so I can mention the solutions suggested in this thread.

Thanks!

[Jerry_K]

I have five Series three on cable with RG6 wiring exclusively and have never had a problem with ATT cell phones. Sony, Motorola, Nokia phones, many phones many models not one problem with TiVo. Never had any problem with DirecTiVos on DTV either.

So it must be your iPhone. The reason I stay away from anything Mac, from any era hardware or software. If it was originally written for Mac, I refuse to use it. All Mac software tries to take over your computer. Tried Safari for Windows and in less than an hour of browsing had three trojans which needed special downloads to remove.

[netringer]

I have five Series three on cable with RG6 wiring exclusively and have never had a problem with ATT cell phones. Sony, Motorola, Nokia phones, many phones many models not one problem with TiVo. Never had any problem with DirecTiVos on DTV either.

So it must be your iPhone. The reason I stay away from anything Mac, from any era hardware or software. If it was originally written for Mac, I refuse to use it. All Mac software tries to take over your computer. Tried Safari for Windows and in less than an hour of browsing had three trojans which needed special downloads to remove.

I'll address only one aspect of the nonsense above. Before I got my iPhone I used a HTC WINDOWS MOBILE 3G phone on AT&T. Amazingly, the GSM on that phone worked exactly the same way and the interference to very nearby speakers was the same. Oh, and we often hear it because GSM phones are too close to desk phones on phone conferences on work. Most of my co-workers have Blackberry GSM phones. That Apple influence must really be stealthy. :mad:

Can't resist....And it's not like Microsoft software like Windows Media Player tries to take over your PC or anything or that the EU had to sanction MS with $millions in fines to get them to stop it.

[bobkbusch]

Actually, I have seen the problem with four different type AT&T phones, not just an iPhone. Do different cable companies use different frequencies to transmit HD? (I don't have fiber optic, at least not for the end-run.) Otherwise, since you have RG6 and no problems, it sounds like it must be a grounding issue or bad connector as mentioned above.

I guess I should have titled my thread "GSM Phones Cause HD Picture Loss," but that horse is already out of the barn...

[hillstones]

I have five Series three on cable with RG6 wiring exclusively and have never had a problem with ATT cell phones. Sony, Motorola, Nokia phones, many phones many models not one problem with TiVo. Never had any problem with DirecTiVos on DTV either.

So it must be your iPhone. The reason I stay away from anything Mac, from any era hardware or software. If it was originally written for Mac, I refuse to use it. All Mac software tries to take over your computer. Tried Safari for Windows and in less than an hour of browsing had three trojans which needed special downloads to remove.

Windows is vulnerable to a lot of things. Your three trojans had nothing to do with running Safari for Windows. The trojans you downloaded are Windows executable files, they have nothing to do with the web browser. Anything written for Windows tries to take over your computer (Symantec programs are famous for this). You would have gotten the same trojans if you downloaded them from FireFox or IE for Windows. A trojan is found within a program that is downloaded and executed by the user, unaware that the trojan was contained within. My friends are always calling me to remove the spyware and adware that they get through IE and FireFox. Just the normal behavior of Windows and infected websites.

Blame the open-source code that is contained in all browsers on both platforms. The latest hacker convention confirmed that the publicized hack was done with a pre-written program that took advantage of an already known issue in the open-source code that was used in all three web browsers.

I have two iPhones in the house and neither of them cause any problems with TiVo. The OP has an issue with either signal level or unshielded cable lines. Any GSM phone would cause the problem.

[A J Ricaud]

You might also want to check for any unterminated ports on any splitters you may have in your setup. This would allow stray signals to enter as well as leaking r.f.

[oViTynoT]

I think you have a shield problem. RG59 and RG6 are BOTH adequate for carrying CCTV signals. RG6 and 6U is primarily used with satellite LNB connections. The difference between RG59 and 6 is the impedance at the frequency being employed.

If you have poorly terminated connections, or a broken / open shield, it's going to leak like a sieve and let EMI IN as well as OUT.

The buzz you hear in speakers isn't really the fault of the speakers. The RF interference is driven into the speaker cables, and is amplified at the AMP, and returned. It's more an issue with poorly designed AMPLIFIERS having low noise immunity, than the speakers. Though, well shielded speakers will reduce the issue because the AMP won't have anything to amplify. It's easy to blame the speakers because you can HEAR them.

The strangest place I heard that GSM chatter was on an Indian-produced Video-CD of the movie "Phone Booth" that I bought in Bangalore. During one particularly quiet part of the movie, that chatter was obvious. Someone in their production studio had a cell-phone too close to the audio mixing equipment. It CERTAINLY wasn't a speaker's fault, but that chatter got induced into the low-level voltage lines in the signal path somewhere...

[pninen]

GSM phones cause interference into almost everything. Ditch them. Get a Verizon phone.

[Dennis Wilkinson]

Im so confused....... :o Part of what confuses me is the description about High Definition frequencies in the 37 MHz range and RG6 shielding not effective below 50 MHz. Does this apply to cable systems such as Comcast? I don't think GSM transmits/receives anywhere near this range.

The lowest GSM frequencies are well over 300 MHz (and range to about 1.5GHz, if I remember correctly), so you should be fine on that count. RG-6 quad shield is what should be used in most installations these days.

If coax is your problem, then I'd:

- check to be sure the connectors are attached properly
- check that any blank wall plates have terminating resistors on them
- check to be sure none of the cables have hard bends or cuts in them

There's no guarantee that the noise being injected is coming in over the coax, though. Since you can readily reproduce the problem, you might try to see if disconnecting other cables (network/phone/audio) helps reduce the problem (not that you can live with those things disconnected, but it might help prove that the coax is or isn't the ingress point.)

[bobkbusch]

Great suggestions...THANKS! Unfortunately, I'm leaving on a trip tomorrow and won't be home until Saturday, so I can't troubleshoot until then. I'm pretty sure I have some unterminated connectors both on a wall plate and a splitter. Any suggestions on a source for terminating resistors/plugs? I see Radio Shack carries them, but I'm betting there are less expensive alternatives.

Also, I'm curious why it is just the HD channels that are affected.

[rifleman69]

If it was originally written for Mac, I refuse to use it. All Mac software tries to take over your computer. Tried Safari for Windows and in less than an hour of browsing had three trojans which needed special downloads to remove.


So you don't use Microsoft Word or Powerpoint then, as these were both originally written for the Mac.

[argicida]

Wow, if there were not so many of you reporting this I'd think you were imagining things.

[TexasGrillChef]

That happens with every iPhone I've ever seen. It has nothing to do with proximity to AT&T towers; the iPhones are just poorly shielded I suppose.

I wasn't refering to AT&T towers. I was refering to the fact that I was near POWER LINE Towers.

But yout still probably right. The Power Line towers cause their own problems.

The problem isn't just with iPhones. Problem seems to be with MOST AT&T PDA phones. As it happens with the Samsung, HTC, HP, & Blackberry phones as well.

TGC

[netringer]

..
The problem isn't just with iPhones. Problem seems to be with MOST AT&T PDA phones. As it happens with the Samsung, HTC, HP, & Blackberry phones as well.
It's not just smart phones or even AT&T phones. It's the GSM comm protocol which is used around the world. I think the phone can transmit with a 5(?) watt burst.

I dunno when else it sends, but it often does when the phone rings. I guess it signals the tower it hears the notification of the incoming call. My guess otherwise is when the phone handshakes to (re)register with the system, my further guess is sends the strong burst when it thinks it was or is its getting out of range.

[TexasGrillChef]

Here is part of the article I referenced above...

------

...RG6 Dual and Quad Shield don't have the proper type of shielding for the above described applications. It is manufactured using foil shields and braided aluminum shields. The makeup of the shields differs between models. The effective range of operation for foil shields is above 50MHz, which makes them perfect for rejection of radio frequency interference, or RFI, that may have an effect on satellite or cable installations. At frequencies below 50 MHz, however, foil shields are not effective. The braiding on the RG6 Dual shield and the RG6 Quad shield doesn't have enough coverage to work effectively with baseband applications.

The frequencies that are used in High Definition are usually around 37 MHz. For those lower frequencies, an RG59 with an 95% copper all-copper shield is designed to block RFI inclusion at base band frequencies.

------

Im so confused....... :o Part of what confuses me is the description about High Definition frequencies in the 37 MHz range and RG6 shielding not effective below 50 MHz. Does this apply to cable systems such as Comcast? I don't think GSM transmits/receives anywhere near this range.

Since my problem only exists with the HD channels, I'm wondering if this has anything to do with it. The article also clearly states that RG6 is much more preferable for satellite and cable systems as is noted in some of the above posts as well. I want to be armed with as much information as possible when the cable guy shows, so I can mention the solutions suggested in this thread.

Thanks!

Look into GROUNDING.... I had all sorts of problems with the POWER LINE towers near my home. Until I had GROUNDED my cable runs. Once I did that. Interference from the POWER LINE TOWERS went away.

I honestly beleive that if the cable runs in everyones home were properly grounded they would have less problems with interference.

Properly grounded systems will have a cable grounding block and a 12 gauge or better COPPER wire running from the grounding block to a 6' 3/8" thick COPPER grounding stake driven it's entire 6' length into the ground.

Give that a try.... It's isn't that expensive either. Only cost me $30 at my local home depot store & I did it myself.

TGC

[TexasGrillChef]

It's not just smart phones or even AT&T phones. It's the GSM comm protocol which is used around the world. I think the phone can transmit with a 5(?) watt burst.

I dunno when else it sends, but it often does when the phone rings. I guess it signals the tower it hears the notification of the incoming call. My guess otherwise is when the phone handshakes to (re)register with the system, my further guess is sends the strong burst when it thinks it was or is its getting out of range.

Probably true. Since my wife & I have only ever used PDA phones, we can only speak from experiance about PDA phones from AT&T.

I agree as well, that the problem is espeically bad when someone is calling you, or when you first initiate the call. Sometime I know I am getting a call even before the phone rings, because of the buzz on my computer speakers.

I have just learned to live with it. I only have the problem with speakers & not my TiVo's, or cable TV. HD or not.

Then again with my Cable TV I do have really good cable & it IS grounded exceptionally well. I have found that the MAJORITY of cable subscribers DON'T have their cable grounded at all, or if they do it's POORLY grounded.

Folks properlly GROUND your cable lines & I am willing to bet, that most (if not all) of your interference will go away!

TGC

[CharlesH]

The problem with GSM phones as used by at&t or T-Mobile is that the transmitter in the phone switches on and off rapidly when in use, and it is that pulsing, not the base frequency it is transmitting on, that causes interference in speakers and such. GSM is a TDMA (Time Division Multiple Access) protocol, where each phone transmits in its assigned time slot. The base frequency (850MHz or 1950MHz) is above what is used for cable. On the other hand CDMA (Code Division Multiple Access) phones (like from Verizon Wireless or Sprint) transmit in a continuous lower power fashion across a fairly broad frequency channel, and do not cause this interference. In fact, without receivers specifically designed to recognize the signal and knowing the specific encoding variation that phone is using, the transmission is indistinguishable from white noise.

[oViTynoT]

The problem with GSM phones...Not really a problem. The problem lies with cheap amplifiers that don't reject external EMI.

The only thing in my house that I hear this on are:
My PC speakers
My cheap clock radio.

Everything else seams immune.

However, it's certainly more convenient to blame the phone... :) Have you ever been in a broadcast or recording studio? All the ones I've been have signs: "No cellphones beyond this point" because of the risk of that noise getting into the signal path....

[Xunaka]

The proble isn't the iphones or AT&T at all, you have badly insulated lower grade cable problem RJ5 or lower series.. Simple sollution call comcast have them run you a new arial. Then run new lines in your home that are RJ6 or better.

256 QAM is just RF streamed over cable wire, if you have bad insulation any other RF will obviously cause issues..

[DaveDFW]

I ran this test at home several weeks ago. This was an interesting experiment for me--I never would have guessed a cell phone would be interfering with the cable signal.

I tested with a blackberry on AT&T wireless, and placed the phone near the Tivo. While it's ringing or making a call, I lose signal on HD channels from 825mhz up to 855mhz, except for the three at 837mhz for some reason are unaffected.

I have to go about 15 feet away from the Tivo before the signal clears up.

Our other cell phone is Sprint, and nothing it does interferes with the Tivos no matter how closely it is placed.

Really nothing can be done, except keeping the AT&T phone away from the Tivos, or replacing the existing lines with shielded coax.

TTYL
David

[bobkbusch]

Here's an update....

I did some troubleshooting and then had Comcast try to fix the problem.

I had a splitter that only had one cable out, so I removed the splitter. No help.

I don't have any other "unterminated" wall plates or splitters in my system.

I had one cable running through an APC H15 Line Conditioner/Surge Protector, to one of my Tivos. I removed the cable from the H15 and ran it straight to the Tivo. This helped! I still get interference, but I have to be much closer to that Tivo.

Comcast replaced almost every connector on every cable in the house. He also checked outside for proper connectors, etc. This did not help.

The Comcast tech checked and said my cable is properly grounded.

He also stated I had RG6, "single shield" cable on most of my runs. He wasn't sure if that is the problem, so he escalated to a supervisor and I'm waiting to hear back. He also stated that Comcast is aware of the problem because he remembers them discussing it at a "weekly" meeting about three months ago. He doesn't recall hearing about a solution.

I'll wait to hear back from the supervisor and if nothing useful, I'm going to unhook everything and run a single RG6 quad-shield to one of the Tivos and see what happens. Replacing the cable inside the house is apparently my responsiblity, if I want to do it; and I don't!

[TexasGrillChef]

There is only one culprit to the problem. However, there are several solutions. The Solution that works for you may or may not work for someone else.

The Culprit is AT&T and the phones that are on their system. The problem is with ALL AT&T based cell phones. Motorolla, Samsung, HTC, Apple, Blackberry, Palm, Nokia, Sony, etc... Some phones are better than other phones at reducing the EMI that they produce. None the less, the problem for whatever reason you want to claim is with AT&T and the phones. Sprint, Verizon, T-Mobile don't have this problem. (with a few very rare exceptions)

Here are the list of things one should check &/or do to prevent EMI issues with any of their electronic equipment.

1. Keep the phone as far away as possible from the other electronic equipment that you have EMI issues with. In the case of the OP.... his TiVo's... in my case speakers. Although I am sure I would have issues with my TiVo's too if my phone got to close to them. Not a problem for me as they are installed in a enclosed cabinet and closet.

2. Check your cable. Connectors, grounding, age & quality, length of runs, how many splits, spitters, terminators, & even how many devices are connected to the cable.

3. Check your electrical system in your house. Some houses aren't very well grounded. When I had a hot tub installed a few years ago & needed a 240v 50amp circuit installed. I found out that when my house was built they used ALLUMINUM grounding wire & grounding stake, yet my house has copper wire in it. Go figure. I also installed a whole house EMI filter & Surge protector at my Circuit breaker box. ($130 + $50 install). The EMI filter on my electrical power system reduced alot of the EMI 60hz buzz I heard coming from alot of my speakers. Then again I live very near a 250,000 volt power lines as well.

4. I plug my TiVo's, Computers, & other electronics into GOOD UPS systems that have good EMI filters built in as well. This helps with issues when you run electric motor driven devices in your home, or microwaves.

5. One trick is you could put your TiVo's into a Faraday cage. That would block all EMI coming into the TiVo's except what is picked up by any cables that run into the cage. (Except optical cables as they aren't prone to EMI).

6. And lastly... if the problem bugs you bad enough, you can switch carriers! LOL :(

TGC

[DaveDFW]

...
5. One trick is you could put your TiVo's into a Faraday cage. That would block all EMI coming into the TiVo's except what is picked up by any cables that run into the cage. (Except optical cables as they aren't prone to EMI).
...
TGC

I laughed when I read this, but then thought about it some more. Maybe a small faraday cage just around the tuners inside, and not the entire Tivo enclosure?

I'll see what I can cobble together at home later and report back. :)

TTYL
David

[RossoNeri]

GSM phones cause interference into almost everything. Ditch them. Get a Verizon phone.

All GSM phones everywhere do that. With GSM "the RF transmitter is turned on/off at a fast rate, and that 'pulsing' is often picked up by nearby devices that don't have good RF shielding. In the case of GSM the pulse rate is 217 Hz, which can be easily heard." Google "GSM buzz" for more info.

The better the speakers are shielded the closer the phone needs to get to pick-up the buzz. My phones usually have to be within 5-6 feet (2m) of a speaker to pick it up.

Verizon won't really help. VZ's announced 4G wireless technology is GSM/UMTS based LTE. As far as I know, there is no reason to expect that future VZ phones won't have the same effect.

Remember, GSM = "Global System for Mobile communication". I doubt we'll ever be able to get away from it.

Sorry if this is too off-topic.

[T-Shee]

...

5. One trick is you could put your TiVo's into a Faraday cage. That would block all EMI coming into the TiVo's except what is picked up by any cables that run into the cage. (Except optical cables as they aren't prone to EMI).

...

TGC

When my Series 3 was first setup with cablecards in 2006, I began to experience channel dropouts when I was standing in a certain spot in the room. I could walk away from that spot and the channel would reappear!

I live in NYC where there's a constant RF blizzard: cellphones, microwave relays, hundreds of WiFi networks, you name it.

I came to the conclusion that the tuner section/cable-card section of the S3 is poorly shielded, so I built a Faraday cage (of sorts) from old steel fero-typing plates that I had in the closet. Though not completely shielded like a true faraday cage, I put the plates above and below the S3 and grounded the lower plate, the one nearest the tuners/cable-cards. It worked, and worked well enough that they've been in my equipment rack ever since.