Is there a way to simulate a Public Switched Telephone Network (PSTN) call signal?

[birchesgreen]

I have a few GPO telephones in my collection of junk i mean retro technology. I do not have a land line though so if i want to hear the 746s and 722 trimphone i have ring then i have to take them to my Mum's land line.

However, soon the PSTN network will be withdrawn so even that awkward option will be out. Is there any gizmo available which can simulate the call signal to make a phone which is connected to it ring out?

 

[Devonian]

I've never used them, as my 746 lives on a landline and my 232 is connected to VOIP, but Bluetooth-landline adapters, such as the 'XLink BT', are available which pair with a mobile phone and allow calls to be placed/received on an external telephone, including old GPO phones. They usually have US-style RJ11 sockets (but may come with a BT plug adapter) and probably have a US-style ringing pattern. Some, including the XLink will accept pulse dialling from a rotary phone - but may be more sensitive than a GPO exchange to the speed of the dial.

You can also connect GPO phones to standard VOIP services (but not proprietary services like BT Digital Voice) via an Internet router with an Analogue Telephone Adapter (ATA) such as the Grandstream HT801, which will accept pulse dialing. These need an RJ11 to BT adapter with a bell capacitor to make a GPO phone ring.

For completeness, rotary (or most push-button pulse) phones can be converted to tone dialling for use with tone-only systems such as BT Digital Voice using a plug-in adaptor such as the 'Dial-A-Tone' or 'Dialgizmo'.

 

[Ediswan]

Should be possible. If I recall correctly, the 'ring' signal is something simple like 50V DC, pulsed for the brr..brr...........brr..brr.

Most internet content discusses the ring tone played to the caller, which is a different beast.

 

[birchesgreen]

Thanks Devonian i'll take a look at XLink BTs. Unfortunately i'm 17 years too late to ask my old man who was a telecoms engineer, and indeed spent his days commissioning TXE4 and System X installations!

 

[Puffing Devil]

You could also buy a small home PBX, this would allow phone to phone calls as well as ringing. I have an Orchid PBX at home which we use to feed a number of lines around the place using structured cabling.

A cheaper alternative would be to find a local Radio Ham and get them to knock you up a simple box with a 48V transformer switched to the appropriate pins for the phone.

 

[Energy]

I have a few GPO telephones in my collection of junk i mean retro technology. I do not have a land line though so if i want to hear the 746s and 722 trimphone i have ring then i have to take them to my Mum's land line. However, soon the PSTN network will be withdrawn so even that awkward option will be out. Is there any gizmo available which can simulate the call signal to make a phone which is connected to it ring out?

Do you want to call people using it or just have it ring? For TV and theatre work they have ring generators which just make them ring, though they are suprisingly expensive.

A pulse to tone converter may be an option.

 

[John Webb]

Should be possible. If I recall correctly, the 'ring' signal is something simple like 50V DC, pulsed for the brr..brr...........brr..brr....

Minor point - it's 50-80volts AC needed to ring the old-style bell. The bells have a magnetically-polarised hammer which swings from side to side. And to keep the bell from disturbing the DC signalling and speech side of things there is a capacitor in series with the bell - so DC voltages won't do anything to the bell.

Do you want to call people using it or just have it ring? For TV and theatre work they have ring generators which just make them ring, though they are suprisingly expensive.

A pulse to tone converter may be an option.

An alternative is to find an old army field telephone; these have a hand 'magneto' generator which produces the necessary AC voltage.

 

[najaB]

You can also connect GPO phones to standard VOIP services (but not proprietary services like BT Digital Voice) via an Internet router with an Analogue Telephone Adapter (ATA) such as the Grandstream HT801, which will accept pulse dialing. These need an RJ11 to BT adapter with a bell capacitor to make a GPO phone ring

Second this. In the past I connected a rotary telephone to a Voyager 220 and it worked with old BT Voice. I've no doubt it would work with a less geriatric ATA.

 

[birchesgreen]

Yes i don't really want to receive calls just hear the phones ring out now and then for nostalgia reasons. I was hoping there was an easy and cheap way to do it!

 

[dgl]

Might be an idea to also ask over at the Vintage Radio forums, www.vintage-radio.net/forum

 

[sor]

You can also connect GPO phones to standard VOIP services (but not proprietary services like BT Digital Voice) via an Internet router with an Analogue Telephone Adapter (ATA) such as the Grandstream HT801, which will accept pulse dialing. These need an RJ11 to BT adapter with a bell capacitor to make a GPO phone ring.

Although many ATAs, including virtually anything made by Cisco, do not support pulse dialing. You'd need a converter as you mention for BT DV. If you were to do that you'd need to make sure that the one you're buying actually does support it, and that it isn't locked to a specific VoIP provider.

A cheap PBX might be a better bet IMO.

 

[Devonian]

Yes i don't really want to receive calls just hear the phones ring out now and then for nostalgia reasons. I was hoping there was an easy and cheap way to do it!

In which case, as 'John Webb' suggests, a field telephone or stand-alone magneto ringer will excite the bells without complication. However, a GPO/BT linesman's telephone with built-in ring generator might be a more appropriate option given your father's profession! E.g. the 704 or 286.

'Energy' is right that stage ringers are usually an expensive option: our theatre group uses a battery-mechanical alarm clock with telephone gongs attached to get the authentic sound without the expense. Others have been known to use a suitably powerful audio amplifier and play a sine wave tone through it to generate the AC voltage.

 

[Adwy]

The current BT Digital Voice hub will have a socket for old-style telephones and will ring them. It will also allow outgoing calls, anlthough only tone-dialled.

I’ve just checked ours and so can write the above.

 

[richa2002]

Adwy is right. We have a 746 phone hooked up to Digital Voice via the home hub and it receives calls fine.

 

[birchesgreen]

Might look at going back to BT when i can, VM are really annoying me now. Bought a 741 yesterday so now have four dialphones and no landline.

 

[david1212]

Might look at going back to BT when i can ....

While the number of ISP's offering home phone from their router is limited with Vodafone there is no charge so significantly less than BT. For outgoing calls either PAYG or add a package.

The downside of Vodafone is that they have teamed up with CityFibre. Hence if already in your area you will have to be connected using it not Openreach FTTC (Fibre to the Cabinet i.e. the connection from your premises to the to nearest connection cabinet is the same copper as BT use). If in time CityFibre install in your area existing Vodafone customers will get swapped to it.
I'm unsure what happens with Vodafone if Openreach install the fibre network in your area.

You state

... VM are really annoying me now...

I presume you mean Virgin. I thought they offered home phone from the router. I've no idea of the costs though.

 

[birchesgreen]

I presume you mean Virgin. I thought they offered home phone from the router. I've no idea of the costs though.

No you have to pay extra but i pay enough already!

 

[Energy]

No you have to pay extra but i pay enough already!

BT charges an additional £5pm for PAYG, £6pm for unlimited uk. Prices are flat, with no reduction in bundling it

VM charge £5pm for Weekend & Evening, £10pm for Anytime, £15pm for International Anytime.

Sometimes with VM you unfortunately have to phone up and got to retentions and you should quickly get new customer pricing (its 1->4->4 on the phone tree). Its improved slightly but I'm not sure if the deals auto offered over email are the same yet.

 

[birchesgreen]

Phoning up VM is akin to walking through the gates of Hell.