17-05-2017, 03:06 PM
What a brilliant article written in the early days of transistors. I didn't realise that 70MHz was possible in 1952. Transistors only got better from there.
Some of his remarks about valves are not correct. As Tommy Flowers knew back in 1940, valves can have a very long life so long as they are powered continuously and used comfortably within their ratings. This fact was used in Colossus, in telephone exchange equipment and from 1956 in undersea telephone cables. In this last application where reliability was paramount the designers used a fairly old fashioned type of valve as its long term reliability was better understood than later valves or early transistors.
Some of his remarks about valves are not correct. As Tommy Flowers knew back in 1940, valves can have a very long life so long as they are powered continuously and used comfortably within their ratings. This fact was used in Colossus, in telephone exchange equipment and from 1956 in undersea telephone cables. In this last application where reliability was paramount the designers used a fairly old fashioned type of valve as its long term reliability was better understood than later valves or early transistors.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
