BT CD 1000 no longer works after switch to digital voice

[Smudger_Smith]

Hi

Since the switch over to digital voice, the BT DC 1000 which used to show me the phone number of incoming calls, no longer works. Is there a reason for this. The information is shown on the screen of the BT Verve 450 ok.

[imjolly]

which is connected to the socket on back of hub?  how/where is BT CD 1000 connected

[Smudger_Smith]

@imjolly 

After the switch to digital voice I removed the old master socket and  the old twisted pair. I replaced the now unused master socket with a pair of parallel phone sockets, transferred the blue/white, white/blue and orange/white conductors to the rest of the house sockets using a Krone key. I then used an extension phone cable to connect from the smart hub to one socket of the pair. The local BT Verve phone I connected to the other socket of the pair. All extensions throughout the house work fine,  the exception being the BT CD 1000 which no longer indicates the number of any caller.

[Keith_Beddoe · Accepted solution]

@Smudger_Smith 

The BT CD 1000 is a very old device and may not work on a DV line as I believe it may need a line polarity reversal signal during the initial ringing phase.

Manual https://telephonesuk.org.uk/wp-content/uploads/2020/10/Caller_Display_1000.pdf

[Smudger_Smith]

@Keith_Beddoe 

Many thanks. I was looking for such an answer. So I'll go looking for a replacement that will work with DV.

Thanks again.

Smudger

[ptan]

Quick update to this.

I have a CD1000 and it does not work when plugged into the back of the Hub.

From another tip on this site I found that I could still use my old Tribune handset plugged into a DV adapter and get it to ring properly if I fitted one of the old ADSL microfilters to provide the 'ring' wire. Bingo that worked.

I then tried the CD1000 in the adapter with the microfilter and it displayed incoming call IDs. Great.

Plugging in a microfilter into the Hub socket and then the CD1000 into that you get IDs being displayed. Great

All those old microfilters have a second lease of life to offer