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[sevenlayermuddle]

I would be tempted to dismantle it and remove the 470 k Ohm resistor from the circuit.

Why?   

[tickmike]

On my first post...."I also need to attach a larger outside bell on my workshop, so could I take the feed from this face plate ?."

So it should be ok to use Pin 3 and 5 to connect my Ex GPO type 67A outdoor twin 6" gong bell .

[sevenlayermuddle]

An extension bell would worry me because, if I understand right, it represents a massively imbalanced interference pick up.   If the DSL filter were perfect that would not matter.   But filters are not perfect and, presented with signals that are large enough in amplitude, may fail to 'protect' the DSL signal.

Emphasise, above is based on hunch not scientific analysis.   

[burakkucat]

Why?   

Why not? 

The across-pair shunt is not required at a extension socket. The only purpose of the shunt in an NTE5, which is installed as designed -- as the master socket, is to provide a suitable load and frequency response so that the exchange equipment recognises the line as intact when no telephone is currently connected to the circuit.

[sevenlayermuddle]

Why not? 

Because life is limited, and if we're to apply that principle to all things I would spend my remaining years doing things that are pointless, to exclusion of more worthwhile activities, simply because there is no reason not to do them.    

[burakkucat]

On my first post...."I also need to attach a larger outside bell on my workshop, so could I take the feed from this face plate ?."

So it should be ok to use Pin 3 and 5 to connect my Ex GPO type 67A outdoor twin 6" gong bell .

Is this the bell? Bearing in mind 7LM's caution, just go ahead and test it. Yes, IDC3 & IDC5 would be the correct connectors from the lower-front face-plate.

[tickmike]

I think it's the one I've got to find it as it's in a safe place if only I could remember it's location.

As it's not a 'trembler' type bell there should not be any interference  would leaving the resister in circuit help to dump it back to pin 5 / 0v ? if there was ?.

[sevenlayermuddle]

My reservation regarding interference pick up is based on the assumption that when the circuit is quescient, one side of the pair will be connected to the bell magnet's coils.

If that assumption is wrong, my reservation evaporates.   

[burakkucat]

. . .  would leaving the resister in circuit help to dump it back to pin 5 / 0v ? if there was ?.

No.

All we could say is that there would then be the bell's resistance (1 k Ohm, if I remember correctly) in parallel with the 470 k Ohm resistor.

The effective resistance would then be 998 Ohms. Hence the shunt would then be 1.8 microfarads in series with 998 Ohms. How that would react in the circuit I do not know! All I will say (trying to justify my reason for removing the 470 k Ohm resistor, for 7LM) is that I would prefer to have a shunt made up of 1.8 microfarads in series with 1 k Ohm (the resistance of the bell) across the pair!

[sevenlayermuddle]

Actually, I'm thinking both sides of the pair are effectively connected to the bell coils, one directly, the other via the ring capacitor, which have extremely low impedance at DSL frequencies..   So it's probably not that imbalanced after all. 

Further analysis welcomed, though I'm off to sleep now.   

Or as B'cat suggests, just try it and see.

[burakkucat]

Actually, I'm thinking both sides of the pair are effectively connected to the bell coils, one directly, the other via the ring capacitor, which have extremely low impedance at DSL frequencies..   So it's probably not that imbalanced after all. 

Yes, I'll agree with that.

. . . though I'm off to sleep now.

Something that I, likewise, should do!