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Phone switchover to 21CV

On our wavelength

I've just had an email (not had a letter) telling me my phone will be switched to 21CV at the end of March and I need a technician visit as I have an old (V2 I think) router,

1. Can someone arrange for a letter to be sent to me please?

2. I use the Virgin router simply as a modem and have my own router equipment. Will this still be possible with the new router that Virgin will be fitting?



To get the connection logistics straight

I have a VM PSTN Master socket downstairs behind my TV unit which is hard to use

I have five extension sockets, 3 phones and one Ansafone connected.

One of the Extension sockets is next to the Hub3 upstairs.  In fact on Brackets to keep it high to give good wireless coverage.

So, is the VM VOIP adaptor an RJ11 to BT style plug or BT style Socket please?

And you really need to get the Chat Help team properly briefed as regards CV21 and the various options we already have in our houses for PSTN type connection.  Master near Hub, Extension near Hub, No sockets near Hub.



Hi @stephenbrowning 

Welcome back to the community forums. 

The adapter will look like the image I have provided below. You can find further information on the home phone switch over here if needed. 




Here to help 🙂
Virgin Media Forums Agent

Hi there, 

Thank you for confirming the adaptor you will send is an RJ11 (connects to Phone socket on the Hub) to a BT style 6 pin socket (pins 1 and 6 no connection).   

Which is only of use to those with a single phone located near the hub.

Or useless to those with existing Master+Entension socket network in their house without modification of same. .

And I see from the link you posted to the other Forum Article that a number of the thousands of VM Customers who have such Master plus extension cabling have been questioning you.  

And as regards that thread citing DECT wont mean anything to the Customer.  I think you changed to Cordless (Wireless with Sender unit plugged into a BT Socket) which they should understand.  

Certainly a case or neither OFCOM or VM properly understanding the practical consequences of the 21CV change.  As I said before you also need to properly brief your Char Advisers.  They had to go off and find the image you posted using Google when I quizzed them.       



And as regards the link I posted

As they say in the text there is an error on the top diagram

Capacitor C1 is connected between Pins 2 and 3.
The ringer unit in each phone is connected between pins 3 and 5 and only responds when a ringing (AC) signal is sent from the exchange along the A wire (Pin 5) and the B wire (Pin 2).
That signal stops when you pick up the call.



Please also see the OFCOM page

For those (you or anyone you know) who reply on the PSTN Phone for Emergency calls..... And who dont have broadband.

(Also Noting that the Cellphone (Mobile) System cannot be guaranteed to continue to operate with a Power Cut). 

Will VoIP phones work in a power cut?

Unlike traditional phones, a phone connected to a broadband router will not work in a power cut, as the router gets its power from the mains.

If you rely on your landline - for example, you don’t have a mobile phone, you’re unable to use a mobile phone  or you don’t have mobile signal inside your home - your provider must make sure you are able to contact the emergency services during a power cut. This could be in the form of battery back-up so your landline will continue to work, or giving you a basic mobile phone to use in this situation.



And this page linked from the OFCOM site is worth looking at.



@stephenbrowning wrote:

And this page linked from the OFCOM site is worth looking at.



Are you asking how you can get your phone extension sockets to work post-switchover or just pointing out some of the flaws in VM's customer switchover info?

Worth noting (if you are using multiple corded telephony devices) that the REN of the phone connection from the VM hub seems to be 3 per line. Topics on here have reported issues when some customer reach 3+ devices.

Thank you @stephenbrowning for your posts and we are sorry that you are feeling apprehensive about the change over. 


We do offer a back up battery that can allow a phone to contact emergency services in case of an update that is available to customers who need it. You can request it when you book in your appointment or we can arrange an appointment to have one installed after the switchover should a customer decide that it is necessary.


Thank you to goslow for their response here, and to clarify, do you have any specific questions or concerns that you we can assist with?  



Thanks to GoSlow and Ash.

So, Virgin have not only not provided comprehensive information to deal with existing wired internal installations it now seems they also cannot provide the current normal PSTN Ringer Equivalence Number (REN) capability of 4?     Anything else we need to know?