My mother's DECT phone system has stopped displaying the number (or name, if
the number is in the phone's address book) for incoming calls. It used to
work until a few das ago. I'm trying to work out whether the Caller ID data
is not being sent (ie a problem with her phone provider) or whether a
setting on the phone has got changed so as not to display the CID even if it
is received.

1471 lists the number of the most recent incoming call. Is that separate
from Caller ID - can you have a situation where 1471 logs the number but CID
is not sent when the ringing tone begins? The phone provider is either BT or
PlusNet - I'm not sure whether she's changed the voice calls from BT to PN,
to match PN as her ISP. I think she has done, but neither of us can remember
for certain.

On 20/10/2023 15:21, NY wrote:
> My mother's DECT phone system has stopped displaying the number (or
> name, if the number is in the phone's address book) for incoming calls.
> It used to work until a few das ago. I'm trying to work out whether the
> Caller ID data is not being sent (ie a problem with her phone provider)
> or whether a setting on the phone has got changed so as not to display
> the CID even if it is received.
>
> 1471 lists the number of the most recent incoming call. Is that separate
> from Caller ID - can you have a situation where 1471 logs the number but
> CID is not sent when the ringing tone begins? The phone provider is
> either BT or PlusNet - I'm not sure whether she's changed the voice
> calls from BT to PN, to match PN as her ISP. I think she has done, but
> neither of us can remember for certain.

If Plusnet are in anyway invloved with her phone provision, the problem
is very likely something with their apalling phone account managment
system, and the utterly utterly hopeless website portal.

I've had no end of trouble switching on and off call forwarding, and
voicemail on both her account, and mine over recent years. Very recently
(owing to the NHS's ability _not_ to forget about our landline number
(another story) I tried to activate Call Forwarding for one month only.
Plusnet managed to not only not activate it, but also cancel Caller
Display. And things still are not right, because the portal says three
weeks later 'awaiting activation'

They've clearly thrown the towel in early, as of course they will have
zero phone line customers after Dec 2025.

Rant over

On 20/10/2023 15:21, NY wrote:
> My mother's DECT phone system has stopped displaying the number (or name,
> if the number is in the phone's address book) for incoming calls. It used
> to work until a few das ago. I'm trying to work out whether the Caller ID
> data is not being sent (ie a problem with her phone provider) or whether a
> setting on the phone has got changed so as not to display the CID even if
> it is received.
>
> 1471 lists the number of the most recent incoming call. Is that separate
> from Caller ID - can you have a situation where 1471 logs the number but
> CID is not sent when the ringing tone begins? The phone provider is either
> BT or PlusNet - I'm not sure whether she's changed the voice calls from BT
> to PN, to match PN as her ISP. I think she has done, but neither of us can
> remember for certain.

Yes, caller ID is separate from 1471.
When BT swapped my line to Digital voice, they automatically put it on
Call Protect, with no obvious way to remove it. There was also a suggestion
that CLI would not be delivered whilst on Call Protect, but that did not
happen. My DECT phone shows CLI whether registered with the Smart Hub
itself or the original base plugged into the back.

If she is with BT, you may need to access the account details through
their website and update some settings. Plusnet may well be similar.

On Fri 20/10/2023 15:21, NY wrote:
> My mother's DECT phone system has stopped displaying the number (or
> name, if the number is in the phone's address book) for incoming calls.
> It used to work until a few das ago. I'm trying to work out whether the
> Caller ID data is not being sent (ie a problem with her phone provider)
> or whether a setting on the phone has got changed so as not to display
> the CID even if it is received.
>
> 1471 lists the number of the most recent incoming call. Is that separate
> from Caller ID - can you have a situation where 1471 logs the number but
> CID is not sent when the ringing tone begins? The phone provider is
> either BT or PlusNet - I'm not sure whether she's changed the voice
> calls from BT to PN, to match PN as her ISP. I think she has done, but
> neither of us can remember for certain.

Suggest you start a thread with a subject of 'Ping Bob Pullen' - he is
Support at PN and very helpful if he sees your post.

On 20/10/2023 15:21, NY wrote:
> 1471 lists the number of the most recent incoming call. Is that separate
> from Caller ID - can you have a situation where 1471 logs the number but
> CID is not sent when the ringing tone begins?

BT's analogue system sends caller ID before ringing current is applied.
That is the key difference from the Americans. Tones the caller hears
are only very loosely related to what the called party hears.

I'm not sure to what extent other UK operators use the BT system, or the
between first and second ring system.

1471 is done at the exchange and doesn't rely on caller ID having being
sent to the phone already.

David Woolley wrote:

> BT's analogue system sends caller ID before ringing current is applied

But after a polarity reversal.

On 20/10/2023 18:00, David Woolley wrote:
> On 20/10/2023 15:21, NY wrote:
>> 1471 lists the number of the most recent incoming call. Is that
>> separate from Caller ID - can you have a situation where 1471 logs the
>> number but CID is not sent when the ringing tone begins?
>
> BT's analogue system sends caller ID before ringing current is applied.
> That is the key difference from the Americans.  Tones the caller hears
> are only very loosely related to what the called party hears.

I gather that the reason there is no correlation between the brrr-brrr
that the callers and the ring-ring that the called person hears was to
discourage people from passing messages of the form "one ring means I;ve
passed my driving test, two rings means I've failed" without paying for
a call, though in practice you just agree a greater number of rings for
one of the possible answers so it is unambiguous.

> I'm not sure to what extent other UK operators use the BT system, or the
> between first and second ring system.
>
> 1471 is done at the exchange and doesn't rely on caller ID having being
> sent to the phone already.

When you pay your phone bill to someone other than BT, who generates the
CLID data? Is it BT Openreach, requested by your 3rd party phone
provider, or is it the phone provider which generates the CLID data
instead of BT doing it?

Intriguingly, after a week of getting no CLID displayed, my mum has just
emailed me to say that after I phoned her this evening, she started
getting CLID again. I wonder if PN has fixed something. I was about to
phone them tomorrow (on my mum's behalf) to report a potential fault.
Looks as if I don't need to any more!

In article <6sCdneIiLIeFO6j4nZ2dnZfqn_WdnZ2d@brightview.co.uk>,
NY <me@privacy.net> wrote:

> I gather that the reason there is no correlation between the
> brrr-brrr that the callers and the ring-ring that the called person
> hears was to discourage people from passing messages of the form
> "one ring means I;ve passed my driving test, two rings means I've
> failed" without paying for a call, though in practice you just
> agree a greater number of rings for one of the possible answers so
> it is unambiguous.

Back in the day with Strowger, there were ringing machines. these
were quite substantial devices with a motor turning a shaft which in
turn operated cam shafts. The cams pushed spring contacts together
which connected the AC to the line for ringing. In order to spread
the power load these cams had phases so that whilst phase 1 was in
its silence period, the other phases would be ringing.

It was simply to spread the load, sometimes your tones would be in
phase with the ringing but more likely not but a complete cycle had
the same start and end for tones and ringing.

Bob.

On 23/10/2023 09:54, Bob Latham wrote:
> In article <6sCdneIiLIeFO6j4nZ2dnZfqn_WdnZ2d@brightview.co.uk>,
> NY <me@privacy.net> wrote:
>
>> I gather that the reason there is no correlation between the
>> brrr-brrr that the callers and the ring-ring that the called person
>> hears was to discourage people from passing messages of the form
>> "one ring means I;ve passed my driving test, two rings means I've
>> failed" without paying for a call, though in practice you just
>> agree a greater number of rings for one of the possible answers so
>> it is unambiguous.
>
> Back in the day with Strowger, there were ringing machines. these
> were quite substantial devices with a motor turning a shaft which in
> turn operated cam shafts. The cams pushed spring contacts together
> which connected the AC to the line for ringing. In order to spread
> the power load these cams had phases so that whilst phase 1 was in
> its silence period, the other phases would be ringing.
>
> It was simply to spread the load, sometimes your tones would be in
> phase with the ringing but more likely not but a complete cycle had
> the same start and end for tones and ringing.

I knew about the various phases for the ringing machines, but I thought
the ringing tone that the caller heard and the ringing current that was
sent to the called person's phone were *defined* to be on different
phases, rather than a matter of chance. Otherwise they'd have made sure
that the two ringing currents were always fed off the same phase, which
was chosen at random from the several (how many?) that were available.

I wonder if there are phones sold now which actually use the ringing
current to drive the ringer in the exact cadence of the current, rather
than locally synthesising a ring-ring (or any of the weird and wonderful
tomes that people choose).

It is weird to hear the local ring-ring of our DECT phones and also the
genuine BT ring-ring on my old corded phone (if I happen to have left
that plugged in from when I needed it during a power cut). Not only are
the two out of phase, but they also have slightly different mark:space
timing.

Bob Latham wrote:

> Back in the day with Strowger, there were ringing machines. these were
> quite substantial devices with a motor turning a shaft which in turn
> operated cam shafts. The cams pushed spring contacts together which
> connected the AC to the line for ringing. In order to spread the power
> load these cams had phases so that whilst phase 1 was in its silence
> period, the other phases would be ringing.

The same (or similar?) machines that generated the ringing voltage also
generated the ring tone and engaged tone, if they went wrong you could
get 'happy accidents' such as this ...

<https://youtu.be/RWZ4pve5Mkc>