If you're encountering problems with your phone lines, it can sometimes be very difficult to pinpoint where the issue originates. If a property in question is older, you could be facing challenges associated with outdated infrastructure, poor workmanship or technologies that have since been updated. How can you begin to unravel your challenges?
Network or Private?
First, you need to determine where the network responsibility ends and where the issue will have to be addressed by a private contractor. It's possible that the problem is not internal. Whereas a network issue will be handled and paid for by their contractors, if the issue is within your property you will need to bring in contractors to fix this yourself.
Where Is the Problem?
Locating this 'crossover' point can be more complex if you live in an area where several properties retain service in close proximity, such as an apartment block. In this case, you need to be looking for the main distribution frame, which is the threshold. Backbone cabling will then run from that point to a riser, where cables split off into each apartment.
It's much easier to determine the arrival and departure point in a conventional house, but the process is the same in looking for the most common faults.
It could be a case of poorly attached terminations. This is the point where a cable goes into the socket. There could be evidence of corrosion around the socket and terminals and this can definitely affect signal conductivity and the internal copper wiring.
It's possible that wire pairings are touching and these conductors will then create a permanently closed circuit, shutting off that line altogether. You may also find that the pairings in each cable have become untwisted. These need to be set correctly otherwise the line attenuation will be too high.
It also possible that the PVC insulation has peeled away from the copper, which will allow water infiltration and result in interference.
These issues and others could have been caused by poor installation when the service was first connected or could have been caused by general wear and tear over time. It is of course also possible that there are no issues within your property but that the challenge is to be found within the adjacent network.
Either way, it's best to get a licensed professional to have a look at your installation in order to get to the bottom of the problem and update your telephone cabling if necessary.