On 24th May 2024 4:57pm, Positively Pottering said:
Hi Philip... shared service telephone lines also known known as party lines were commonplace back in the day as there was insufficient line plant and exchange equipment for subscribers to have their own direct exchange line (DEL).
In order to make a telephone call a subscriber lifted the handset and pressed the call exchange button on the telephone to connect to the operator and when direct dialling (DD) was introduced you simply lifted the handset and pressed the call exchange button to get dial tone (DT) and dial the required number.
Shared service telephone lines did not provide privacy as either the 'X' or 'Y' parties dependant on which subscriber was engaged on a call had to wait for the other one to finish. It wasn't uncommon to eavesdrop one another's call.
The method of signalling the exchange to make a call or receiving a call required the use of a third wire connected to Earth and was often provided by a separate wire from the telephones block terminal (BT) to a strap connected to an earth spike driven into the ground at the subscribers premises.
Very often the spike had been sawn short to enable it to be driven easily into the ground or the third wire had simply been pushed into loose soil resulting in the earth connection being too high resistance to call the exchange or receive a call.
Remedy..... just chuck a bucket of water over the spike/wire! 
Many thanks for all the background info on the Coventry telephone exchanges, fascinating stuff.
I well remember the party line system because we had one on the first phone we had installed in about 1960. I was only a kid but from memory recall that few calls were made then, it had to be something really important to be justified. Not like today when some folk seem to spend most of their waking hours 'connected' and glued to their smartphones just chatting away about not much at all really. How times have changed!
