Strange Phone Behaviour - The Sequel

[thescullster]

Hi all

Work related, but trying to sort myself so kind of DIY.

OK so following on from "Siemens Phone not displaying Number" post, I have bought a newer Siemens Gigaset C300A to replace the C460 model.

I have now discovered:

My New Siemens phone in my own telephone outlet socket still does not display caller ID.

Old style (non-roaming) phone plugged into my telephone outlet will display caller ID.

My New Siemens phone in another user's telephone socket (who also has same Gigaset phone incidentally) will display Caller ID.

The various phones have been moved around a few times, so plenty of "power off to base unit" treatment (although that seems irrelevant).

Is this a wiring fault? Do the roaming phones need better "connections" or whatever than the non-roaming variety to allow Caller ID service to operate?

Comments appreciated - I am baffled!

Phil

[Graham.]

Sorry I cant find the original thread is the title correct?

Probebly digging over old ground sorry. Is this a Virgin Cable line or a regular BT line (irrespective of who your *calls* provider is)?

Have you tried it with *everything* else unplugged from the line including any ADSL router and filters?

Has anyone told you how to eliminate all your extension wiring at the master socket, have you tried that?

[Peter Crosland]

Try it plugged into the test socket assuming you have an NTE5 socket. You need to remove the faceplate to obtain access to th faceplate. If it works there then the problem is with the wiring. In my experience the caller ID signal does not always propagate across extension wiring consistently.

[Brian Gaff]

Exactly how is the caller id signal sent. Is it on a carrier or just a series of tones? Brian

[spuorgelgoog]

In the UK it's sent as CCITT v.23 modem tones frequency shift keying in a format similar to MDMF (Multiple Data Message Format) with 15 digits for number and 15 ASCII characters for name

Owain

[Dave Liquorice]

242 CDS Calling Line Identification Service, TE Requirements; Part 1 Idle State, Down Stream Signalling, Part 2 Loop State Signalling.

227 CDS Calling Line Identification Service - Service Description

[Andrew Gabriel]

UK telephony kit is supposed to not care about the line polarity, although there is notionally a right way round. However, some of the UK callerid detection circuits have not correctly handled the line polarity being the wrong way around, so you could try reversing the line polarity to so if it makes any difference. Callerid starts with a line reversal, and in some poorly designed circuits, that's not detected if the polarity is wrong to start with.

[Graham.]

Its a burst of 1200 baud data coupled with a line polarity reversal before the first ring.

Some of Virgin Media's acquisition companies used a DTMF burst. I don't know if there are any of those lines left. In that case you would be relying on the phone being dual mode and information about that is often scare.

[Davey]

In the US, the time and date of the call are also sent at the same time. A new handset waits for the first incoming call before it displays the information. Whereas here, that information depends on the setting in the 'phone. I got caught out when I moved back here, waiting for a call so that the time would be set, to find that it wasn't.

Another feature over there is that, for yet another fee, the name of the caller will be displayed, the information provided by the 'phone company, not by programming of the handset. But they also have the problem that companies with a switchboard don't always send the CLI information, so there is nothing useful displayed at all.

[Mike Tomlinson]

En el artículo , F escribió:

Just killfile Woddles. He never has anything useful to add