Rotary phone

[BADmoon1969]

Just had fibre installed and my old fashioned rotary phone dies not ring as it did with landline connection.

[yorkspark]

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@BADmoon1969wrote:

Just had fibre installed and my old fashioned rotary phone dies not ring as it did with landline connection.

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Are you now on digital voice?

[BADmoon1969]

Yes,  had it installed last week as part of a new contract (no choice).  I have vintage phone which would always ring (very loud bell) when I had an incoming call.  The ring has now stopped working since fibre digital voice fitted.

[yorkspark]

fit one of these to the phone, it will recreate the ring wire needed

[WSH]

The microfilter plugs into the Smart Hub 2 and provides the “third wire” required to ring very old phones.  You then plug the phone into the microfilter, of course.

[BADmoon1969]

Hi, I’ve got one of these, but it does not seem to work!  Where exactly do I plug it?  The engineer said that the voltage signal had now changed with digital voice and there now wasn’t enough power to make the vintage bell ring!

[WSH]

I've not actually done this myself but there have been a number of posts to suggest that is a solution.  It may be the case the not all microfilters provide the third wire and only some makes will work.

As I said, the filter plugs into the phone socket on the back of the Smart Hub and the phone plugs into the microfilter.

Edit: OK, I've just tried two different models I've got to hand with a multimeter.  One does seem to have a connection to the third wire, the other doesn't.  The one that does seem to work is a cheap Chinese thing labeled DSL472.  (That looks suspiciously like the one in the picture but the label is different).

[WSH]

OK, I’m officially confused now.

I’ve just looked up the schematic for a microfilter and it shows the ring wire connected via a capacitor, so testing it with a multimeter shouldn’t have worked.

I’m sure one of the guys from the telecom side of things could answer this better.  @iniltous @36ULW any ideas?

[licquorice]

Ringing current is AC so will pass through the capacitor.

Not sure the hub can supply sufficient current for a high impedance mechanical bell.

[wkirkman]

I have an old GPO 746 rotary phone plugged in with Digital Voice and all works fine. I had to get a Pulse-to-Tone converter to dial 'out' but the ringing works without any change. If it worked before Digital Voice, it will work afterwards (fibre make no difference, no matter copper or fibre, the phone signals come into the house as IP packets just the same as any web page request).

So the question really is… where are you sticking it? It needs to go into the back of the Smart Hub 2 in the green port, and if not, then you either need your old extensions wiring into said green port, or use a Digital Adapter - all very well documented on this forum.

If you are sticking it into an extension socket as you used to, but the extensions are not wired the the back of the Smart Hub 2 green port then it will not work.