customer reports poor telephone communications when using a copper telephone line that also has a DSL se.....?

Question

A customer reports poor telephone communications when using a copper telephone line that also has a DSL service. What is the most likely cause of the problem?

*The DSL modem is incorrectly configured.
*The DSL filter is faulty or not connected.
*The HSDPA (High Speed Data Packet Access) is interfering with the telephone operation.
*The telephone does not comply with the IEEE 802.15.1 standard.

Answer 1

well with only those choices then the obvious answer is a faulty filter, or a line that has not properly been filtered...



but that would not be the only cause of any troubles on the voice side of a DSL circuit...



the first troubleshooting step that i would take would be to have the customer turn the modem off, or disconnect the modem from the phone line to see if it cleared up the trouble - if it did, then the trouble has been isolated to a DSL filter issue, in which case it will have to be determined what on the line has not been properly filtered - for cases where the DSL line is shared with an alarm system it is better to have a professional install the DSL filtering so that the alarm system can also be properly filtered...



if the trouble still exists with the DSL modem disconnected, then advising the customer to plug a corded phone to the NID and check for the trouble there will isolate if the trouble exists inside or outside of the customers location... for troubles that still exist at the nid the phone company must come out to make the repairs - if the trouble goes away further troubleshooting needs to be done inside... static is normally caused by loose or corroded wires or jacks...

Answer 2

I have found instances where I use 2 DSL filters (in series) on a home phone. The voice part of the line is approx. 300-3000 hz. The DSL is data at a higher frequency on the same circuit.. With two filters, I find DSL speed and voice isolation better..

Answer 3

The thing to remember is that DSL and dial tone come from the same place, but not the same equipment. DSL signals will punch through bad phone lines that voice communications will not, notably hum and static. Your DSL signal might be degraded, but still function. (remember the UP TO part in DSL speeds).



You can possibly test for VoIP compatibility (a VoIP function test) to see if the line exhibits phase and jitter problems, you can actually install a SIP or VoIP line and see if it works better than the land line (probably will) or just deal with the telco fixing the voice grade part of your phone line.



Except for the carrier noise, you can probably troubleshoot a phone line without the filter.

Answer 4

The best way to check the most obvious and common cause is to unplug the ADSL modem from the line and take note of any difference to the line condition.

If it improves, it generally means the filter is not connected correctly or faulty.

If a cordless phone, check the configuration does not conflict with wireless modem/router. you can test for this by simply turning off the modem/router and check the phone.



If there is no difference the phone could be faulty or non compliant, so try a different one on the line. Compliant phones for the Australian networks should be appropriately labeled.