How good are Digital voice adapters

[Keith_Beddoe]

Some cables have the wrong pinout at the RJ11 end, as they are intended to be plugged into a phone and not a broadband hub, as some older phones have a a different arrangement, usually those that need a separate "ring" wire. 

Bear in mind that the DV adapter is a two wire presentation, and may not work with older phones that need a separate "ring" wire. This can be overcome by using the "phone" part of a microfilter, as that emulates the missing ring wire.

[rbz5416]

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@Paul608085wrote:

I have never heard of "crossover" RJ11 / "BT" cables - when might they be used?

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Unfortunately there is no standardisation for the pin-out of an RJ11 socket. Whereas the BT 431A has always used pins 2 & 5, hardware manufacturers use either pins 2 & 5 (straight) or 3 & 4 (crossover). So you need to inspect the original cable (probably with magnification) to see where the coloured wires go from one plug to the other, in order to get the correct replacement. Just extending the BT end makes this unnecessary.

[Paul608085]

@Keith_Beddoe @rbz5416 

Thanks for the replies.

I have never come across that potential issue before, and I have been recovering/saving cables from old equipment for re-use since BT first lost the monopoly on providing telephones!

When I first joined BT back in 1981, many of the jobs I went on during the "Customer / Subs Apps Installation" phase of my apprenticeship were converting peoples "hard-wired" phones to the "new" sockets so that they could buy their own equipment.

[rbz5416]

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@Paul608085wrote:

@Keith_Beddoe @rbz5416 

When I first joined BT back in 1981, many of the jobs I went on during the "Customer / Subs Apps Installation" phase of my apprenticeship were converting peoples "hard-wired" phones to the "new" sockets so that they could buy their own equipment.

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Presumably at that point you where dealing wholly with BT phones, which IIRC back in the day had captive leads. I first became aware of the issue in the early '90s with the rise of dialup broadband/fax modems. The two biggest players (Hayes & US Robotics) used opposing RJ11 pinouts. Customers would move desks & equipment around & mix up what appear to be identical cables, then report that their modem wasn't working. Of course omitting that they'd moved it!

It's a lot rarer now with most using straight. But in the garage I still have two carrier bags of RJ11 to BT431A cables, carefully separated. Had to raid them only recently for a mate's Vodafone router that apparently uses crossover.

[Paul608085]

@rbz5416 

"Presumably at that point you where dealing wholly with BT phones, which IIRC back in the day had captive leads."

Yes, up until that time the GPO / British Telecom had a monopoly on supplying telephone equipment connected to their network. All residential and small business customers, (subscribers as they were called back then), would have had a terminal block like this one, that hard wired their telephone to the incoming line. They were not allowed to interfere with this connection. Some people may still have this type of block, to connect the incoming dropwire from the pole, (grey in this photo), to the thinner internal cable running to their master socket.

 

[Check]

A huge thank you to all those who responded my enquiries. I am a 70 year old woman and admitted technophobe. What your replies did, was stop me fixating on replacing the cable on my phone and realising that a simple extension cable, that I could plug my phone into, would do the trick! Why didn't I see that before? I'm still worried about how much my 2 digital voice adapters will increase my energy costs. I'm very concerned that this new system does not guarantee access to emergence services if the line fails in the event of a power outage or an electrical storm. On the news today the energy suppliers say that power outages are unlikely this winter with the caveat there are no guarantees. I guess it depends on your age and your priorities. At my time of life guaranteed connectivity is paramount. On balance I view this as a retrograde step and an inferior service.

[Keith_Beddoe]

In case anyone missed it https://community.bt.com/t5/The-Lounge/Big-thank-you-from-quot-Check-quot/m-p/2317199

[rbz5416]

Without real world consumption figures the 10p/day per adapter is best guess. I might start a thread to see if anyone has one & an energy monitor to provide those.

But rather than running two of them 24/7, it may be better in the long term to buy a multiple handset DECT phone such as the BT4600. Each handset looks to use a maximum of around a fifth of the power of a DVA & will only be using that when charging the batteries. Of course you have the upfront cost of the phones but you may well find them cheaply used on your local Facebook Marketplace as people switch to the new phones designed for the Hub.

[Check]

Thanks again for your help. You have given me options I can think about. Again I'm very grateful.