16 April 2015 – THE AGE OF SPARK WIRELESS BY BRIAN HAWES, G2KQ

Coherer        Morse Inker
Coherer                                                                                            Morse Inker

Brian started by explaining that many persons contributed to the inventions which led to the start of the wireless age. Mentioned were famous names, such as Clark Maxwell, Heinrich Hertz and Edouard Branly. It was Branly’s invention of the coherer that was used in all early detection of radio waves. In 1894 Prof. Oliver Lodge demonstrated reception of signals by wireless, a full year before Marconi. Unfortunately, he didn’t pursue the matter commercially as Marconi did.

Message communications of the time were by telegraph over cables and many people saw no need for anything different. However, the Navy could see the benefit of being able to communicate with ships once they had left harbour. Marconi focused his attention on that aspect and in 1901 the first high power transmitter was built at Poldhu in Cornwall. High power equipment was also fitted on ships being built at that time. However, the communications were not primarily for safety or nautical aspects, but for the convenience of passengers who wanted to send messages at 2 shillings and sixpence each, an eye watering £55. in today’s money!

After the Titanic disaster, authorities agreed that ships should carry wireless as a safety measure and provide a full time radio watch. 1910 to 1920 saw the end of spark transmissions, mainly due to the invention and use of the thermionic valve which allowed amplification of signals and ushered in the era of voice communications.

Brian had a display of working Morse tape inkers and coherers which members were invited to inspect and try out! Not the usual museum pieces under glass!

Brian demonstrating an inker
Brian demonstrating an inker