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Standard User deleted
(deleted) Sat 21-Oct-06 11:22:56
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Re: Noise margin change


[re: deleted] [link to this post]
 
Not if I'm a tightwad!
Standard User mossmanfly
(member) Sat 21-Oct-06 22:25:31
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Re: Noise margin change


[re: deleted] [link to this post]
 
Will try that.

We have the master socket in the kitchen so I can plug my router into that. How my current connection is done, is a phone cable coming from the master socket (wired in not an adaptor) that runs upstairs, then theres a connector(1) box outside the room that takes a line to my parents room and another to the PC room which ends with the normal phone socket on the wall.

This ring wire where would it be? Main socket of the house? I'll get my dad to have a look and see what we can do. Would be good to solve this for the future when I do get switched onto Max.

I will reboot the router tonight and see if that makes the margin increase, as if its say 3db and after a reboot it turns out to be 13db, there cant be that much change in only a few seconds.

The BT engineer was a phone one, but at the time we did say it was particular for ADSL. I just remember we did have to have a 2nd guy out as we had a new boiler that British Gas fitted and they had to pull up the floor boards and they actually ripped out the wire from the connector box(1).
Standard User deleted
(deleted) Sat 21-Oct-06 23:51:48
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Re: Noise margin change


[re: mossmanfly] [link to this post]
 
The ring wire will be connected at the master socket (wire #3), and it's fed to all the other sockets. You need to disconnect it at the master socket.

Edited by deleted (Sat 21-Oct-06 23:52:14)


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Standard User mossmanfly
(member) Sun 22-Oct-06 00:48:33
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Re: Noise margin change


[re: deleted] [link to this post]
 
Thanks, i'll have a look at mine and see how it is. So no need to mess with any other socket for the ring wire? Just the master? Might just wait and see what happens and if I do get Max and I run into instabalities I know to have a good test of internal wiring as one of the main areas.

Well I just rebooted the router and within the 20-30 seconds it takes for a reboot it the noise margin went from 0db to 18db. So I think something is up with the router reporting it incorrectly. I suppose it could have a . As from what I have read a low noise margin should give you and unstable connection and also slower, but mines always solid and speeds never drop.
Standard User deleted
(deleted) Sun 22-Oct-06 08:37:03
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Re: Noise margin change


[re: deleted] [link to this post]
 
In reply to:

The ring wire will be connected at the master socket (wire #3), and it's fed to all the other sockets. You need to disconnect it at the master socket.



It's best to disconnect it on all the sockets.

The whole purpose of the ring wire is to allow a short circuit to be placed across the ring wire and one leg of the line when any of the phones are lifted.

If you leave the ring wire linking all the extension sockets then when a phone inserted in any of those sockets is lifted you will be back to having the ring wire connected to the line and acting as an aerial.

Ian
Standard User deleted
(deleted) Sun 22-Oct-06 10:41:03
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Re: Noise margin change


[re: deleted] [link to this post]
 
Sorry, but you are wrong. The ring wire was solely there to feed the 75V AC ring signal to old phones which required it to drive old-fashioned bells in the old style phones. The ring wire (#3) is fed from the A wire (#2) via a 2mF capacitor in the master socket - this capacitor passes the ring signal, but blocks the 50V DC. Unfortunately the ring capacitor also passes any HF signals floating around, including strong MW radio signals picked up by the relatively high-impedance ring wire, which are passed back through to the A wire via the ring capacitor. Placing a short across the ring wire would have no effect because it would be blocked by the ring capacitor.

If your theory was correct, then phones would not work at all if the ring wire was didconnected, and they all do. Even the old ones will still work - they just don't ring. Fortunately most modern phones don't need the 75V AC signal, but it's wise to check after you've disconnected the ring wire. There's nothing to stop you cutting the ring wire at each socket - you're just giving yourself more work to do, with little or nothing to gain.

Edited by deleted (Sun 22-Oct-06 10:42:25)

Standard User deleted
(deleted) Sun 22-Oct-06 11:04:37
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Re: Noise margin change


[re: deleted] [link to this post]
 
Well, it's not worth getting into a big debate about it but I have always known it to be provided for anti bell tinkle purposes.

Originally multiple phone installations were provided serially and one phone being picked up would interrupt the ringing circuit for the other phones (the good old plan 1A).

With the advent of the plug and socket system and it's parallell wiring this could not work and, as pulse dial phones were the norm, dialling on one phone would cause the bell in all the other phones to tinkle.

The third wire was the way to get around this by allowing the bells to be short circuited when any phone was picked up.

Ian
Standard User deleted
(deleted) Sun 22-Oct-06 11:25:02
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Re: Noise margin change


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Oh come on ! Are you seriously suggesting that any phone made in the last 20 years is going to have a "bell tinkle switch" ? If any phone in the house was old enough to have one of those, then you wouldn't be cutting the ring wire anyway.

Standard User deleted
(deleted) Sun 22-Oct-06 11:39:35
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Re: Noise margin change


[re: mossmanfly] [link to this post]
 
Any chance you can borrow a modem or router? That would enable to to eliminate your current router as the cause of the drop, or confirm it is the router. That said, the sort of drop and recovery you have described is more likely to be down to noise, imo. When you re-synch, the modem negotiates a whole bundle of new frequencies, so an improvement in noise margin is quite normal.
Standard User deleted
(deleted) Sun 22-Oct-06 11:54:06
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Re: Noise margin change


[re: deleted] [link to this post]
 
There's no point in disconnecting the ring wire on extension sockets with plug-in filters, because that terminal isn't connected to anything. Plug-in filters only connect to pins 2 and 5, and contain their own ring capacitor for the benefit of old phones which need it.

If on the other hand you use a filtered faceplate you should keep the ring wiring connected throughout. It won't interfere with the ADSL signal because it's on the filtered side of the connection.

Eric
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