Noisy phone line and ring capacitor query

Talk Electrician Forum

Help Support Talk Electrician Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Sebastian

Junior Member
Joined
Aug 5, 2010
Messages
9
Reaction score
0
Hi,

I've a client with a very "noisy" line that has been confirmed by her telephone service provider.

Only has two telephone sockets in her apartment.

The Master socket is not used (that being the noisy one - hearing a caller speak is nigh on impossible at times.

She has a fixed (corded) telephone and a wireless router on the other socket and the phone quality is tolerable but her broadband speed fluctuates and can drop to under 200kbps download and 9kbps upload with a ping of almost 500 (main exchange, where her line is generated is only 2km away).

Have checked and even replaced the Master socket but no joy.

I also observe, however, that her one and only extension socket also has a ring capacitor - as has the Master socket, of course.

Could this be part or all of her problem? Her telephone service provider want to charge the national debt to send one of their technicians out and she's a poor potless senior citizen.

Any advice greatly appreciated.

PS. I noticed, when I changed the master socket, that there was a lot of verdigris build-up on the copper contacts inside the LJU (the socket being located on a single course brick wall and obviously exposed to the elements a little, as a result).

Thanks guys (and gals). :)

 
is the master an NTE5A? if so, you should be able to remove bottom plate and isolate house wiring side, and plug a phone into the base of the socket. if its still faulty, then fault is most likely external to property. if tis fine, then fault inside

 
As Andy has said, isolate the master socket to see if its the installtion or external to it. If its happening on the master with nothing else connected then get BT in. They will say they will charge blah blah blah.... but if its only their kit your connecting to now then it must be their kit.

Have you tried a corded phone?

Also, try isolating the ring wire and leave the 2 signal wires there as the cordless phone wont need them and you say you have another master too.

 
As Andy has said, isolate the master socket to see if its the installtion or external to it. If its happening on the master with nothing else connected then get BT in. They will say they will charge blah blah blah.... but if its only their kit your connecting to now then it must be their kit. Have you tried a corded phone?

Also, try isolating the ring wire and leave the 2 signal wires there as the cordless phone wont need them and you say you have another master too.
Unfortunately, a previous tenant has already been at the Master socket and it's not one supplied by the service provider so they can now say "not our equipment, so pay us large quantities" etc., etc.).

re the phone, I think you misread the OP cuz it already is a corded one. She only got a small gaff and doesn't need roamer (is also quite traditional and likes her phone to be in the hall - where they always used to be in the "olden-days"). :D

 
Yep did mixed up the wireless of router with phone. DOH.

I would suggest isolating the internal wiring from the socket and testing again. If its still aproblem then get BT out. If they comment on the socket then tell the customer to play dumb and say thats how it has been since she moved in and when she became a BT customer so as far as she is concerned thats what BT supplied and its not working as advertised.

 
Thanks for all the help.

I'll do the isolating as generally suggested and hopefully the problem will be off-property.

Will get back to you with the results.

 
Have you tried fitting an ADSL filter? You make no mention of there being one.
Yes.

What raised this issue in the first instance is that I'm installing the lady's first Broadband connection.

I carry a range of DSL filters and have tried "known-good" filters but we still get the, clearly audible, line noise.

That was the reason for my suspicion about both the Master and the sole Extension socket having been fitted with a Master LJU. I know that they both contain a Ring Capacitor and as a DSL filter also contains a Ring Capacitor, I was wondering if there might be some sort of "feedback" issue (like when you place a microphone too close to a speaker). You can see I'm not a telephone engineer but I do have an understanding of computer electronics, tolerances and interferences and often find most problem solutions turn out to be clearly logical (after the solution has been arrived at, that is). My career is a kaleidoscope of exhilarating hind-sights - lol.

I find it odd that both sockets are "noisy" but the Extension is operable - both for voice and data - yet the master can't be used for either voice or data communication.

My logic dictates that it should be the other way around. If the Master is poor, how on earth can an extension, connected to a faulty feed, provide a better signal than that which it is receiving? ?:|

All very odd, if you ask me:|

 
big issue with the extension having a cap(it adds onto your REN allowance), never ever use a master for an ext socket,

the other issue is, are your filters passive or active? makes some sort of difference depending how far away from the exchange you are apparently.

just cut the cap out and see what happens.

 
Solved (for now, at least - knowing Telecom as I do, who can ever truly know?).

I did as suggested (thanks for the advice guys) and isolated the Master (simply a case of unhooking the extension wires) and it was still noisy.

I took apart the LJU housing and found that the numpty wot had fitted it had all-but severed the B/W lead as it came out of the sleeving (are profanities permitted on the board???? bad day explode ). It actually fell off as I stared at it in amazement.

To cap matters, I couldn't feed any more cable through as it had been cut to fit Nett bad day explode

So I had to carefully cut a new access hole in the cavity wall above and pray that the cables were dropped to the LJU point and not running horizontal.

Joy. I felt the cable give a little as I carefully chiseled into the plasterwork.

Made myself a Heath Robinson-esq cable hook and fought like a bear with the cable dangling until I realised that not only were both feed and leach cable taped together, but the cavity wall had also been filled with (since hardened) expanding insulation foam (lordy-lordy, did I sweat like a pig, or what?!).

Trimmed it, hooked it up, perfect. No noise.

Attended to the still noisy extension and replaced the coverplate with a non-ring capacitor LJU.

No noise.

Maybe I missed my vocation. Should have gone into telephone engineering thirty years ago. LOL

Thanks again chaps.

 
Top