AGM followed by 'From Cocoa Tins to Glass'. A talk by Derek Cotterill

Registering for this event assists us in planning the seating.

We’ve all heard people say that a telephone calls would have been better over wet string…… try it.

When I started the above was often true as everyone had a dedicated pair of copper wires between talker and listener. Distances were great and capabilities were stretched to their technical limits.

Everything to do with technicalities like power, decibels, equalisation and amplifier design had to be worked out by slide rule and built individually on site. BBC Sunday morning church services from rural churches had a BT (or Post Office) engineer on site to transmit the music and singing over the vicar’s telephone line back to Broadcasting House.

Data transmission didn’t exist and the teleprinter was the modern means of sending written messages at a maximum typing speed of 40 wpm.

Leafield Radio Station had 80 180ft aerials for transmitting international telephone calls to Canada, South America and other countries. The receiving radio station was Rugby. Leafield remained in use till the 1970s while the first Transatlantic submarine voice cables were laid in the late 1950s but had small capacity. One booked a call and waited hours for your turn. Those cables were all co-axial copper and heavy.

Then, today, everything is transmitted via glass fibre. No one has a dedicated circuit as everything is packetized. Data speeds have so many noughts behind the numbers that capacity is unbelievable.

Submarine cables are light and easily laid, they are even ploughed into the seabed.

All this in 50 years and I’ll explain the evolution in non technical terms.