I am in the South West Wilderness of Tasmania,  a week’s trek across precipitous mountains to the nearest habitation.  There is buzzing and ringing in my trouser pocket.  I reach for my mobile phone, a slim lozenge about the size of a box of tablets.  It’s my son in England.  ‘Happy Birthday, dad!, he says.  I am delighted but not amazed. I take it for granted.  But a hundred years ago, his greeting might have just reached me by my next birthday. 

 

It was on December 12th,  1901, that Guglielmo Marconi, waiting patiently in a small shack beside a kite aerial in St Johns, Newfoundland, heard a signal, a repetitive series of three pulses – the morse letter ‘S’, generated from a similar shack in a field at Poldhu, near Lands End in Cornwall.  It was very faint, but its significance was vast.  For the first time, a signal had been transmitted across the Atlantic. They had told him it couldn’t be done.  The power needed to generate a signal was enormous, the aerial vast and even if the signal could be transmitted, it would never follow the earth’s curvature but go straight into outer space.  But Marconi was obstinate.  He believed the signal would stay close to the earth.  It did.

 

Discoveries never come out of the ether.  Science favours the prepared mind.  But what prepared a hitherto unknown Italian’s mind to make this leap of faith 3000 miles across the Atlantic Ocean?   Did Marconi get the inkling of radio waves by interference on the telephone, like when somebody operates a vacuum cleaner and it produces white noise on the radio?  Probably not, though it is of interest that the British physicist, David E. Hughes, observed that his induction apparatus produced a noise on his telephone receiver.  He presented it to The Royal Society in 1878, but the reception was not good.

 

There was a wealth of observation leading up to Marconi’s experiment.  From the 16th century, mariners had noted that lightning strikes perturbed a compass needle.  On 21st April 1820, the Danish physicist, Hans Christian Oersted, observed that a compass needle deflected when he turned the current from his simple battery-operated circuit on and off.  Later, James Clark Maxwell developed his theory of electromagnetism.  He declared that light was a propagating disturbance in an electromagnetic field and postulated that different frequencies of oscillation gave rise to different forms of electromagnetic radiation.  Radio waves transmit at a much lower frequency than other electromagnetic waves and a much longer wavelengths.  In fact, it is possible for man to generate a weak radio signal by waving a charged stick.   

 

Marconi was not the first to capture and transmit radio waves.  Heinrich Hertz used a spark gap transmitter and a long aerial to send a signal to a coil of wire with a gap.  When activated, the receiving coil generated a spark and produced a signal.  Hertz realised as early as 1886 that radio-waves could travel over some distance, but declared his observations of no use whatsoever. It was the Serbian, Nikola Tesla who first developed radio as a form of communication, beating Marconi by two years, but Marconi, by the use of enormous aerials and powerful generators, was able to transmit over longer distances and realise the commercial potential. Tesla accused him of stealing seven of his patented ideas, but by that time, his more extravagant claims had led to him being ignored as an archetypical mad scientist. 

 

For his leap across the Atlantic, Marconi used a simple interrupted high voltage spark between two charged poles.  This was amplified and transmitted via an aerial the circumference of a field;  his receiving aerial a long wire carried aloft on a kite   Radio 4 LW operating at a wavelength of 1500 metres, still requires an aerial of 750m to generate the long wave.

 

Improvements in technology (thermionic vacuum tube valve, sensitive coherer receivers, automated tone generators) rapidly increased radio’s scope and potential.  On March 8, 1916, The American Radio and Research Company (AMRAD), broadcast the first continuous broadcast in the world from Tufts University under the call sign 1XE. The company soon broadcast a daily schedule of dance programs, university lectures, weather forecast and bedtime stories.  British public broadcasting commenced in 1920 with Dame Nellie Melba’s rendition of The National Anthem from the Marconi factory in Chelmsford.  In 1924, a short wave signal was beamed (narrowcast) from Poldhu on the tip of Cornwall to Marconi’s motor yacht anchored off Cape Verde Islands in the South Atlantic.  In 1936, the first television image was transmitted. 

 

The ability to transmit a code over long distances made the world a much smaller and more immediate place.  Improvements in technology meant that more signals could be passed more quickly and the code could be reconstructed in images or speech or pixels on an internet screen,  But in essence the signal was the same, a simple on off switch, but it could be encoded by adjustments in amplitude (AM) or frequency (FM), or more recently phase – like syncopation. 

 

The path to discovery involves informed observation, vision, experiment, but also enterprise and backing. Marconi could see the prospect of commercial radio from his simple faint code transmitted across the Atlantic to Newfoundland, he had the energy to promote and the backing to develop it.  But the implications of his achievement are said to have both excited and scared him.

 

‘Have I done the world good or have I added a menace?’, he pondered. 

 

We might still wonder.  We exist in a post Marconi electronic age.  Our computers and mobile phones increase our communication and efficiency.  We can organise our  business, keep in touch with family and friends and carry out many of our domestic tasks without ever having to leave our desk. But has Marconi enriched our lives?  Is our communication as meaningful?  Have we enough time to reflect?  Are we more healthy?  I don’t think so, but such is the price of progress.  Good or menace?  Maybe that’s a futile question.  Marconi’s bequest just is.   It challenges us to adapt. 

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