Noisy phone line

[ChrisR]

BT say it's something in the house.
The house has half a dozen extension points, and two mains powered phones.
It has an RF alarm, and two RF thermostats, & a wireless network.

Phones used in the house get lots of hissing and crackling, so much they're barely usable.
I was using one, and the lady turned the hob light (filament bulb) on, and the crackling got louder. She turned it off and the crackling slowly went down. It seems to be pretty general, nothing specific causing it.

The electrics are all pretty modern, quite a lot of it, 2 CUs, sockets in the garden and all that.

When I arrived the ingoing BT line went inside the gas pipe's sleeve ( ) so that had to be rerouted, but it made no difference.
All the other wiring is hidden.

All I could do would be put an oscilloscope on the line to look at it, and go round disconnecting things.
Any other suggestions? What would pros do?

 

[Infidel]

Well find the nte whip off the front plate get an ordinary corded phone plug in and see if you get any noise on the line, ( dial 1 to remove dial tone and listen for any pops or crackles) make sure no internal sockets are connected.
I suspect you have a lot of rf interference, try switching channels on your cordless make sure your adsl filters are all ok swap out with a good one.
If your broadband works ok I would not expect it to be a line fault,however this is not always the case

 

[drgl]

What would pros do?

Fit an 80B RF3 & hope!! All you can do is find the NTE5(assuming you have one)& try the test socket. If you have noise there then there is nothing you can do to fix it(other than try an 80B RF3).

 

[Note]

if you do not have a mains NTE BT cannot charge you if fault ends up being in your extension wiring as you are unable to disconnect it.

if its in your extensions they will disconnect them and fit a NTE5A to leave you with a good clear line. no charge.
if noise is on main line they will fix it and fit NTE5A. no charge.

if the noise is crackling and the line tests ok it is a partial break in the line. your BB could still work perfectly as it only uses one leg in the pair.

ring BT call centre explain you do not have a NTE5A and ask for line test. they will always tell you it is in your premises to cover themselves. if line test ok its a partial break or your extensions either way they cannot charge if you cannot disconnect extensions from BT maintained line.

 

[ChrisR]

Well it's a dead classy installation...


BT have been, and pronounced the problem to be not theirs.

Presumably it could also be a short to Earth somewhere?

 

[drgl]

I've seen MUCH worse than that.

 

[Note]

if its in extenions i would assume they are daisy chained together. you will have to track the cable as best you can and disconnect it in sections to see which section is cauing the fault.

if wiring is behind skirting boards and under floor boards this could cause noise as the cable gets rubbed through over time. also if someone put a staple through the cable it could also cause the fault.

you may be better getting the internal wiring replaced altogether

 

[drgl]

You need to follow the advice in post 2 before you start worrying. Dial 17070 for quiet line test.

 

[ChrisR]

I'm tempted to have a go with a milli-ohm meter/ a megger / the mains...

 

[Infidel]

I'm tempted to have a go with a milli-ohm meter/ a megger / the mains.

That would be ill advised as quite what you hope to see looking back up the line apart from 50v dc is not much , all testing usually requires looking from the exchange to the nte , admittedly you may have a rectified low or intermittent battery one leg but I believe the modern tester does all of this.
The newer lads on the block can advise, (been gone a long time now but keep up to date)

Unplug all your phones and plug in a good corded phone into the extension sockets one by one if you get a hum trace the cable back and disconnect.
Does your broadband work?

 

[simonpolly]

A loud crackle is normal caused by a dis fault,A hum is caused by a earth fault do you have broadband on the line ?

 

[xr4x4]

cracking can be caused by broadband on the line with no ADSL filter.