Do old NTEs stink?

Surely just old men!

In reply to a post by BatBoy:

I can't see the reason for the master socket. Why was it fitted?

I've only just seen the point of that post .

If there is an NTE5 already in the flat, ouch! If there is no NTE5 at all, then what?

So presumably there is an NTE5B in the Comms room. Or maybe even an NTE5A. ([paranoid] Which makes snooping a fun game. Especially if there are any disagreements between tenants and landlord [/paranoid]).

Maybe someone knows if two NTE5s on the line could cause this whistle. I doubt it, but I'm just a bod.

Sorted. Ta.

Two NTE's is regarded as 'poor practice'.....

but never seen it causing a problem whenever encountered

But why would it suddenly 'stop liking the OP's set up' ?

It makes me wonder whether the DECT phone and filter can be tested when connected in the comms room, with the extra wire to the home disconnected.

That might show whether the problem occurs with just BT wiring.

Otherwise, the basic question is ... what creates whistles? Unless it is a noise being actively created, the answer is surely from some form of tuned resonant feedback from an amplifier. You would presume that adding a filter alters the resonant frequency, thereby making it audible. Having two phones connected makes a subtle change to that resonance, making it inaudible again.

On the other thread, someone opined about sidetone - which is a deliberate feedback mechanism. I wonder if this can be tested by using a mute button on the handset - which ought to disconnect the microphone, and stop the feedback.

If this is the case here, then almost any change to the "tuning" components of the circuit - resistance, capacitance or inductance.

In reply to a post by WWWombat:

It makes me wonder whether the DECT phone and filter can be tested when connected in the comms room, with the extra wire to the home disconnected.

That might show whether the problem occurs with just BT wiring.

Otherwise, the basic question is ... what creates whistles? Unless it is a noise being actively created, the answer is surely from some form of tuned resonant feedback from an amplifier. You would presume that adding a filter alters the resonant frequency, thereby making it audible. Having two phones connected makes a subtle change to that resonance, making it inaudible again.

On the other thread, someone opined about sidetone - which is a deliberate feedback mechanism. I wonder if this can be tested by using a mute button on the handset - which ought to disconnect the microphone, and stop the feedback.

If this is the case here, then almost any change to the "tuning" components of the circuit - resistance, capacitance or inductance.

Just tried muting - no difference.

No idea. But if using corded phones only and no noise then it is a work around.

Everyone is guessing and the issue sounds like it will require a decent engineer to solve the issue.

In reply to a post by broadband66:

No idea. But if using corded phones only and no noise then it is a work around.

Everyone is guessing and the issue sounds like it will require a decent engineer to solve the issue.

Thanks to all for input

I have another engineer visit scheduled for Thursday 9th March.
I will push the issue of testing the DECT phone directly on the BT line in th comms room so ruling out all of the non-BT wiring in this place.
Then hopefully will go from there.

In reply to a post by Shadoogie:

In reply to a post by broadband66:

No idea. But if using corded phones only and no noise then it is a work around.

Everyone is guessing and the issue sounds like it will require a decent engineer to solve the issue.

Thanks to all for input

I have another engineer visit scheduled for Thursday 9th March.
I will push the issue of testing the DECT phone directly on the BT line in th comms room so ruling out all of the non-BT wiring in this place.
Then hopefully will go from there.

Problem SOLVED

Engineer was new into the job by only few months - young man with excellent approach.
His first move was to fit an Openreach adsl splitter plate at the master socket.
Whistle still present.
He then pulled the wires out of the plate that fed to the star wired extensions.
Whistle gone.
Replaced the wires - with difficulty in those new compression fittings and reversed their polarity.
Whistle stayed gone.
Brilliant - only trouble is I have the router/hub in a broom cupboard with no power socket, but I am sorting that shortly and using powerline adaptors to feed the LAN signal to my TV and BT box location.

Thanks for the suggestions and help guys - just brilliant!

Geoff