Marconi: Between Earth & Air

Distance

Distance - Hermeet Gill

Distance - Hermeet Gill

Marconi first sent radio signals from one end of a room to the other, in the attic of his family home in Italy.

Soon he was sending messages ...

... 400m over the London rooftops …

(could radio waves even travel over water?)

… 8.7 miles across the Bristol Channel …

(yes. Turns out: more easily over water than over land)

(what about over the horizon - beyond where we can see?)

… 18 miles across the Ligurian Sea ...

(yes - over the horizon too)


 ​



... and beyond.

Marconi’s achievements attracted the attention of kings and queens, the Italian Navy, and Lloyds of London. ​

He communicated the news of the death of Gladstone to London during a snowstorm. 

He transmitted messages from the Speaker of the House of Commons across the Thames.

He provided sports coverage of the Americas Cup off the coast of the US. ​

He published the first newspaper printed at sea, from news gathered before reaching land.  ​

At the request of Queen Victoria, he set up a radio link between Osborne House and the Royal Yacht anchored in Cowes, where her son, the Prince of Wales, was recovering from a knee injury. 

The scientific view at the time was that — since radio waves travel in straight lines — the curvature of the earth limited the range of radio transmission.

Marconi had sent messages across the English Channel and was convinced it was possible to transmit across the Atlantic.  ​

The attempt was hugely costly and he experienced continuous problems, including the huge aerial masts collapsing in gales on both sides of the Atlantic, bad weather, and the need to change one of the chosen sites. 

Transatlantic S - Hermeet Gill

Transatlantic S - Hermeet Gill

On 12th December 1901 with an aerial suspended from a kite at Signal Hill, St John’s, Newfoundland Marconi reported that he had finally heard the three clicks of Morse code for the letter “S”, transmitted from Poldhu in Cornwall.

Marconi chose “S” because three dots would sound distinctive over the noise of static.

He was also concerned that the equipment the most powerful spark transmitter ever built — might break down if he tried to send a dash. 

“serenely ignoring the curvature of the earth”

“serenely ignoring the curvature of the earth”

“serenely ignoring the curvature of the earth*” *actually: bouncing off the ionosphere.

* Actually: bouncing off the ionosphere

“serenely ignoring the curvature of the earth”

“serenely ignoring the curvature of the earth”

“serenely ignoring the curvature of the earth*” *actually: bouncing off the ionosphere.

* Actually: bouncing off the ionosphere

Holding this receiver to his ear, Marconi heard the three clicks of Morse code ("S"), the first radio message sent across the Atlantic.

Marconi’s Transatlantic Receiver
Collier-Marr Company · English · 1901
Inventory № 96661

The receiver is a horseshoe magnet enclosing a solenoid (which converts electrical signals into sound).

This was one of the most efficient receivers available to buy at the time.

It was modified with extra coils of wire wrapped around the magnet, which may have made it even more sensitive.

Q

Marconi's Transatlantic Receiver

Marconi's Transatlantic Receiver

"Can you hear anything, Mr Kemp?"

Can you hear anything, Mr Kemp?

"Can you hear anything, Mr Kemp?"

Can you hear anything, Mr Kemp?

Distance - Hermeet Gill

Distance - Hermeet Gill