GE Answering Machine Makes Phone Ring Continuously

Is it a two wire system or three ? I think that most of mainland North America is two wire which might make what I'm about to say irrelevant, but it might give a clue.

In the uk, there are three wires once the incoming two wires have gotten past the first or ' master ' socket. They are the 'A' leg, 'B' leg and ' Ring Return '. The ring return goes back to the B leg via a capacitor in the master socket.

The trick is then if you get the A and B legs crossed over anywhere after the master socket. The result is a continuous ring on every phone, similar to what you describe, although it usually happens as soon as you plug equipment into the ' crossed ' socket.

I take it the problem only occurs with the answer machine ? Could it be faulty ? Have you tried it in a neighbor's house ? Have you tried it as the only item on the line ?

Arfa

Tuesday, August 30, 2005 2:22 PM Pacific Arfa, Thanks for your suggestions. I will look into them. Thank you for trying to help out, Earl Williams, Surrey, British Columbia

Arfa,

The three wire system with the ring return common cap at the master phone does not usually apply to modern telephones which use an electronic ringer circuit. With older electromagnetic ringer phones you had to use the third wire to avoid all the paralleled 2uF caps in every phone bell circuit loading down the line and distorting audio frequencies and dial pulses. The third wire/common cap was vital to prevent bell tinkling during dialling for rotary dial phones in par'l.

With electronic ringers and dtmf these problems don't apply and a simple 2 wire parallel connection for phones is the usual method of wiring (depending on REN you might connect 4 - 5 phones in par'l without problems).

I also remember that around 1960 they brought out an "anti-tinkle" device (thermistor) which connected into the bell circuit for use when connecting BPO334 model(and similar) phones in parallel on a two wire circuit. It wasn't all that successful either.

Ross

Ross

Whilst I would agree that modern phones with electronic ringers don't in theory need the third wire, and indeed phones picked up in the US and designed for 2 wire systems work fine in the UK, the UK system is never-the-less still designed as a basic three wire system, with a master socket having a ring return capacitor connected to pin 3. Slave sockets are connected into the system via a three wire cable connected between pins 2, 3 and 5 on all sockets ie a parallel system.

This is in contrast to the old system to which you are referring, where a dial up phone extension was connected as a ' plan 1A ' with the signal circuit being a sort of parallel one, but the bell cicuit being a sort of series one. I say "sort of " because of the way the ( complex ) cradle switch wiring interacted with the overall scheme depending on whether a phone was on or off hook.

You are correct that there was a ' simple ' variation of the plan 1A which involved adding the anti tinkle thermistor, and as I recall, little if any changes to the instruments' internal strapping.

However, coming back to the current system in the UK, it IS still a three wire system, and equipment designed specifically for the system, and carrying the BT approvals sticker is, as far as I am aware, still 3 wire requiring. If you don't have the third wire, the equipment won't ring. If you cross the A and B legs on the extension ie connect 2 to 5 and 5 to 2, then the whole system will ring continuously, but as I said, usually as soon as you plug equipment into the ' wrong ' socket, rather than when a call comes in.

Arfa