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A voice device behind the ADSL splitter? (longish)


A voice device behind the ADSL splitter? (longish)

Hiya. I currently have a BT voice line and I use a V90 modem with an F9 dialup account. I know plenty about IP and ethernet, but precious little about voice and ADSL.

On the wall of my bedroom is the BT white box with the line to the telegraph pole coming out the back whcih the BT fitter installed. In front are many voice devices.

However, we recently fitted a burglar alarm with a dailer device. When the alarm goes off, it telephones me.

Instead of the dialer having a regular phone plug, the alarm fitter wired it directly into the white box. (So an intruder can't just unplug it.) The cable from the dialer disappears into the bottom of the white box, where it is presumably connected to the same wiring points as the front end socket.

This all works very well, but would it still work with ADSL?

If I'm reading this correctly, all voice devices would need to come off an ADSL splitter gizmo, including the alarm dialer.

Here's one possibility... I leave the alarm dialer where it is, but have the other voice devices (my telephone and answer-phone) off the splitter gizmo.

Would the alarm dialer still work? If I'm reading articles on the subject correctly, there will be some noise on any voice device not going through the splitter. How bad will it be?

All I care about is that the alarm dialer can dial out with DTMF, the voice message is at least half intelligable, and that the alarm will recognise my "press 2 to confirm" DTMF response.

If the noise is acceptable when the ADSL is off or idle, will it still work if (say) I leave a big download running over the ADSL as I go off for work, switching the alarm on.

If not, here's a second possibility...
I get someone to replace the BT white box with an integrated splitter unit, and have them wire in the alarm dialer directly into the voice side of the splitter.

Is this possible? If so, who could do it?

Any alternative ideas please? Suggestions? Comments?

A voice device behind the ADSL splitter? (longish)

I believe all (but your ADSL modem or router) must be filtered. You can replace the standard BT master socket faceplate with one with a built in splitter. This can be sourced from Clarity - see - who do a very good guide on all things to do with ADSL and BT extensions (see one of the links on the abovbe mentioned pages).

I have one of their ADSL faceplates (as used by BT) and am very happy with it - I do not need any mico-filters on the extension wiring. It evens works with my Sky Digibox.



Edited the url 'cos it didn't work - Thanks Task

A voice device behind the ADSL splitter? (longish)

You can replace the standard BT master socket faceplate with one with a built in splitter.

Sounds great. Can I fit this myself or do need to hire an electrician or even get BT to do it?

Bill, would like to avoid blowing up the local exchange.

A voice device behind the ADSL splitter? (longish)

Follow the previous link and it will tell you all about it!

In short, you can replace it yourself, as the change is made from the 'consumer' side of the BT master socket (the bit you're allowed add extension cabling to) - you replace a plugin faceplate (as shown on this page) and connect your exentsion wiring to the new faceplate.

However, it is probably worth checking that your alarm has been connected correctly to your phone line - it is ILLEGAL for the alarm fitter to wire the alarm to the BT side of the master socket - you are liable for fines etc (not the fitter), see this page for information and advice.

Also, check that you don't have too many devices plugged into the phone line (the sum of the REN number of each device (i.e. alarm, phone, answerphone, sky box, cordless phone, modem etc..) should not exceed 4 - typically, each device has a REN of 1.