The link up took place on 15 March between Cap Gris Nez, west of Calais in France, and the White Cliffs of Dover in the UK. The distance covered was, according to GPS, 20.82 miles/ - believed to be the world's longest ever wireless DMX signal transmission to date.
The experiment germinated from a meeting between dAFTdATA and Luminex at LSI's wireless 'shootout' in 2006. Discussions ensued which resulted in them working together to produce systems that talked to each other. dAFTdATA's Chris Crockford and Fabrice Gosnet from Sonoss, Luminex's French distributors, then started thinking about various ranges of equipment and maximum distances - and the Entente Cordiale project (ECP) was born - an Anglo French experiment to prove that DMX could be beamed internationally across the channel between different manufacturer's equipment.
dAFTdATA approached the UK authorities with regards the legality of the event, and Spike Hughes, manager of Dover's Rescue Co-ordination Centre (Coastguard) gave permission for the Project to use the Coastguard Station at Dover as the signal reception point. This is very near to the site of the first England-France radio transmission by Marconi in 1899.
Essential Lighting - which holds a vast rental stock of dAFTdATA eDMX - supplied two 7K BigLites that were positioned on top of the cliffs in Dover, along with the Avolites Pearl lighting console on the French side, used to control one of them. Sonoss supplied all the Luminex encoding gear, and dAFTdATA all the radio transmission and reception kit.
The receiver in Dover was located on top of a World War II gun battery, approximately 300ft above sea level, overlooking the ferry port. Light and Sound International Editor, Lee Baldock, witnessed the Dover end of the link, whilst Isobelle Elvira from Sono magazine witnessed the Calais end to prove that the signal was reaching its destination in a timely fashion.
The signal went from the Avolites Pearl to a Luminex Art-Net box to a dAFTdATA 5.4 GHz wireless transmitter. This beamed it over the Channel to the dAFTdATA 5.4 GHz wireless receiver in Dover, then into the dAFTdATA Art-Net decoder which then fed DMX out to the two searchlights. The exact frequency used was 5.47GHz, which Crockford and Gosnet checked was compatible with both French and UK outdoor wireless 802.11A transmissions.
Crockford says, "I was always confident that it would work. It was a great exercise in inter-company relations, like-mindedness and teamwork. Above all, it's really put the system to the test, and has lifted the bar to new heights, with regards what is possible for wireless show control systems."
(Jim Evans)
