The Marconi Trans-Atlantic Centenary.12th
December 2001.Poldhu
Cove, Cornwall, England. 
The Remains of Marconi's Original StationView
of the Poldhu site showing the foundations of Marconi's original station buildings, the Poldhu Cove Hotel (left) and the National Trust's Marconi Visitor's Centre/Poldhu Amateur Radio Club (the brown timber clad building (right)). The Poldhu Cove Hotel is now a nursing home and is not open to visitors.
The Foundations in the foreground of the original building are those of the transmitter room, the left background foundations were those of the engine (generator) room.
The sign at the entrance to the site.
The Marconi Centre's Information PlaqueA
plague giving further information about the site, the events leading up to the 12th December 1901 transmissions and other historical facts up until the time the site was abandoned in 1933.
Plaques on the Marconi Monument which give a brief history of the site. Four in total.
Guglielmo MarconiPrince
Guglielmo Giovanelli Marconi - to quote his full title - the Grandson of Guglielmo Marconi - complete with an R.A. Kent Morse Key in front of the new Marconi Centre with the Poldhu Cove Hotel in the Background.
The PaparazziThe
Gentlemen and Photographers of the Press - or perhaps "Paparazzi" may be a little more appropriate name given the Italian connection!
The Thunderer Squadron's Spark TranmitterThe
Spark Transmitter used to recreate the original "S" sent in Morse. The Radiocommunications Agency licensed the "Thunderer Squadron" - a group of Royal Navy Engineering Trainees - to use of 1.7MHz (+/-) for the event.
All this equipment was borrowed from a Museum and dates back to pre First World War. The Tuning inductor and coupling coil are siting on a wooden trestle to the left and the rotary spark gap sits on top of the tuning condenser. The electric motor drives the rotary spark gap.
The antenna loading coil can just be seen (very top left). The bluish-grey tank to the very rear is the main power transformer. The whole lot was enclosed in wire mesh to act a both a rfi screen and also for personnel safety.
This spark transmitter had an RF output of approximately 1.5kW from an a.c. input in the region of 3kw, which means that a lot of power was lost in the system - as a combination of sound, light and heat. The sound emitted by the rotary spark gap could be heard many tens of metres from the transmitter. Marconi's original transmitter which ran some 25kW could apparently be heard in Mullion some 2 miles away!
In addition to the sound and the blue light of the rotary spark gap, there is a very distinctive odour given off by a rotary spark gap which is very difficult to describe - a mixture of ozone and metal vapour from the electrodes (I think!).
So did the Spark Transmitter cross the Atlantic? See below.
From Spark to Space!The
Ford Transit van to the right houses the spark transmitter. The van to the left is the SNG (Satellite News Gathering) used by the BBC for their broadcast coverage of the day's events.
Marconi's Lizard Wireless StationClose
to the Poldhu site, is the Lizard - the Southern most part of the British mainland.
Here Marconi established one of his first experimental stations and this was the receiving station for his first transmissions where he showed that the radio signals would travel beyond the optical horizon. The transmitter location for these tests was at Niton on the Isle of Wight, which is also preserved by the National Trust. The Lizard Station was used by GB2LD to commemorate Marconi's Transatlantic centenary.
The National Trust Plaque at the entrance to the site. 
The National Trust Commemorative Plaque. So
did the Centenary Spark Transmitter cross the Atlantic?Well
- Yes and No!The
following extract is from the website of the Longwave Club of America (www.lwca.org)
"In the immediate aftermath of the December 12th events marking Marconi's famous feat, some sources were reporting that the Royal Navy engineering cadets' "Atlantic Leap" project had confirmed Marconi's claim of spanning the Altantic from Cornwall to Newfoundland with the letter "S" by spark in 1901.
In fact, however, the transmissions on 1.7MHz were not achieving the expected range, due to unexpectedly poor antenna matching. With just three hours to spare, another approach had to be investigated quickly. The actual transoceanic transmission at 1600UTC took place on 17.682MHz instead.
Although the Society of Newfoundland Radio Amateurs reported that the Canadian Forces team kite was unable to fly, and the US Naval Cadets made the actual reception, no mention of the frequency change was made at their Web site. And even as recently as this past Wednesday's news broadcast for amateurs, RSGB was erroneously reporting that the spark transmitter itself had been tuned to the higher frequency. In actual fact, the sound of the spark transmitter was relayed by terrestrial means from Poldhu to a naval shore station some distance away, from which it was beamed to the New World via a modern 10kW transmitter.
We have updated our own story of the event (below, on this page) to reflect the new information, first reported at the RN's own Thunderers Squadron site. The team summarized the day by saying: "Without the use of modern equipment and having to use a much higher frequency we would have never had a re-enactment of that day.
"Although we had to use modern components, the Transmission was a success but failed to prove if Marconi had achieved a crossing that day. To truly prove his achievement, we would need exactly the same atmospherics, no other interfering transmissions and exactly the same equipment. None of these criteria can be realistically met so we came as close as possible to provide some authenticity for the celebrations."
To further update our original story, the VO1S/GB1ØØGM contact with regular ham gear for the Queen's message was apparently a great success. Following the greeting, Lady Mary Holborrow, with the help of Carolyn Rule, MØADA, then sent "S S S" via Morse code to symbolically recreate the event, and VO1S responded with "R R R" to acknowledge reception. The British end of the transmission took place from the Visitors Centre at the Poldhu site, which opened that same day. The Poldhu Amateur Radio Club has some new pages of photos and descriptions of the center's grand opening."
Given that Marconi's original transmitter ran some 25kW, and even then there is still much debate as to whether he actually heard the signal or not, it would have been very extremely fortunate if the Thunderer Squadron's transmitter would have made the crossing.
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Page last updated 13 Oct 2002
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