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trojwl
join:2011-05-16

trojwl

Member

Static in phone line

Had U-Verse installed last week. During install the tech removed the old DSL filter block from NID and replaced with a non-filter block.
U-Verse works great . Unfortunately I now have static that goes away when I unplug modem so the DSL is definitely the source.
However I only get the static on my Uniden 6.0 Dect cordless phones (one base and three remotes). My older AT&T cordless and its one remote are crystal clear as is my corded phone (I have a lot of phones).
I installed one of the three filters included in the self-install kit on the Uniden phone to no avail. The others have no filters and apparently don't need them as they work fine.

Would rather solve this without speaking to the young lady with the funny accent at AT&T.

Any ideas please?

Forosnai
join:2011-09-30

Forosnai

Member

There's always the possibility of your static coming from the wifi in the dsl modem. Worth a shot changing the wifi channel or trying a different channel on the phone, and/or moving the base to a different location.
trojwl
join:2011-05-16

trojwl

Member

I'll let you know if that works.

Thanks
cramer
Premium Member
join:2007-04-10
Raleigh, NC
Westell 6100
Cisco PIX 501

cramer to Forosnai

Premium Member

to Forosnai
It's also possible it's hearing the VDSL RF signal, but it's well below it's 1.9GHz radio frequency, and well above what it should be digitizing for you to hear. Wifi (2.4GHz (b/g) and 5.8GHz (a)) should not cause any interference at all -- DECT is specifically designed to avoid that very problem.

Do you get the same noise with the modem powered on but the phone line not connected to it? Can the called/calling party hear the noise?

* Most people cannot hear 24KHz, which is the lower end of the ADSL/VDSL range. If I plug an analog (no electronics at all) phone in with my ADSL line, I can just hear it when it syncs. Once sync'd, it doesn't use anything below 32KHz, so I cannot hear it at all. (@40 years old, I can barely hear it. And I'm deaf to it in under a minute. )

Forosnai
join:2011-09-30

Forosnai to trojwl

Member

to trojwl
Click for full size
Funny how the specs of the phone say 1.9Ghz... Wont get wifi interference, but the user guide says keep away from networking devices.
trojwl
join:2011-05-16

trojwl

Member

The noise goes away when I unplug either modem power or phone line. It is your typical DLS phone line interference. It is that "scratchy" noise that is similar to what the old DSL signal made on an unfiltered line. I'm sure anyone with halfway normal hearing would be able to hear it if they had the Dect handset in the ear. It is fairly loud. Also the other party doesn't seem to hear any noise.
When using the Dect, the static doesn't really crank up until I press a digit key. I can get static started on handset, run into another room, pick up a corded phone, and I will not hear the noise. I hear it only on the Dect.
I have not moved the Dect base and both it and the modem (both old and new) are in same locations they've been in for the last many years with absolutely no noise issues. I guess I could try moving Dect base further away from modem (currently about twenty five feet apart) but with the long range of the modem that sounds somewhat impractical. Also my house is not that big.
Like I said before, my older (more than five years easily) AT&T cordless phones have zero static.
I can't be the only one with both U-Verse and Dect phones in same house. If this were a bad "combination", it seems this would have been a major issue discussed in these forums.
One more thing. On modem, phone line is plugged into "Broadband" jack (as opposed to"phone lines" jack, which is empty).

I really do appreciate the replies.

weaseled386
join:2008-04-13
Edgewater, FL

weaseled386

Member

I'm trying to picture your setup. Is it possible you have rebranded ADSL vs. IP based Uverse? If that were the case I'd imagine you should be able to hear the static on all phones, but all phones are not created equal. What equipment did ATT install in your home to provide you service? Brand and model (or even a pic of the back of the device) would answer this.
trojwl
join:2011-05-16

trojwl

Member

Numbers on back of modem.
Motorloa NVG510
p/n 581862-003-00
Style GXDSL

Also, after speaking to a knowledgeable service rep on the phone (a rarity nowadays) I was told it is IPDSL.

Thanks,
Warren
cramer
Premium Member
join:2007-04-10
Raleigh, NC
Westell 6100
Cisco PIX 501

cramer to trojwl

Premium Member

to trojwl
As I've said before, you should not be able to hear any DSL. If you hear anything at all it'll be a very high pitch squeel, not a scratchy static (similar to an analog modem, usually heard as crosstalk from a neighboring pair.) What people hear is an artifact of the digital logic in their phone. None of your other phones on the same unfiltered line have the noise. The noise doesn't go away when you put a filter on the line. (a functional dsl filter should block everything above ~10KHz.)

What happens when you disconnect the line at the NID? Leave everything in the house plugged in and on and "unplug the house". That will kill dialtone and dsl, but will see if the modem is generating the noise.

The noise has to be coming from the phone or phone line. It's a digital handset so it's impossible to get static "over the air". Wireless interference creates "dead air", not static. If it's EMI in the base station electronics, it should still be there with the phone line disconnected (from the base itself.) See if it's still there with no line plugged into the base -- dsl and everything else still plugged in and running.
trojwl
join:2011-05-16

trojwl

Member

I disconnected the Dect from house circuit. I could still hear some static in line.
The moment I pulled the power from the modem I could hear a loud click. Also a discernable change in level of noise.
It almost has to be RFI caused by modem. I should not have heard anything on disconnected Dect handset when I de-energized modem.
Also, the base for the AT&T phone set is on the same wire pair entering house and both are no more than ten feet apart.