Aberdeen/Straubing - Deep-sea diving is one of the most hazardous of occupations, with decompression sickness and oxygen toxicity a constant menace. Descents to depths down to 500 metres pose a massive challenge not only to divers and their equipment but also to their support teams: the crews of the dive support vessels that accompany every dive.
DOF Subsea recently commissioned the Aberdeen-based diving equipment specialists Divex to install a communications system in its dive support vessel Skandi Singapore. A key factor influencing its choice was Divex's HeliCom Matrix?, one of the most advanced diving communications systems in the world. Among other things, the HeliCom Matrix? performs the automatic digital unscrambling of divers' voices. This is essential because, due to the extreme depths at which the divers are operating, their gas supply contains a mixture of helium and oxygen that renders their voices virtually incomprehensible – the dreaded 'Donald Duck' effect. What was essential here was to ensure that no outside interference entered the signal chain and that the unscrambling technology could be applied to communications emanating from decompression chambers at a variety of depths. "Divex was commissioned to install a communications system offering up to 30 channels and capable of unscrambling helium-influenced speech," explains Steven Coull, Senior Electronics Engineer with Divex. "The stipulation then was for a further ten channels to support telephone and entertainment systems as well as the remote keypanels." The HeliCom Matrix? from Divex was therefore complemented by an RTS/TELEX system. "After a demonstration of the system, it became clear to us that RTS/TELEX, with its first-class components of a uniformly high quality, offered the solution that best satisfied our requirements," says Coull.
Three Cronus matrices from RTS form the nerve centre of the communications system on board the support ship. The Cronus is a modular, 32-port digital matrix intercom, which is only two rack units (2U) high, but allows in its standard configuration the creation of matrices of up to 128 ports through the combining of multiple units. It is also fully compatible with all keypanels and other peripherals of the RTS matrix product line, can be expanded with analogue and RVON cards, and linked to ADAM/Zeus matrices via trunking.
Two Cronus units on the Skandi Singapore compose the master matrix, with a third providing backup. A TIF-2000A single-line digital telephone interface from RTS permits phone lines to be integrated into the communications network. As keypanels, RTS KP-32 were preferred along with four RTS MKP-4 and thirty RTS WKP-1 wall units.
"The appeal of RTS/TELEX systems lay in their remarkable audio quality. They also offered precisely the functionality we needed," explains Steven Coull. "Our favourites are the KP-32 keypanels because they are simple to operate and pack a host of features into their compact 2U housings." Thanks to Divex's speech unscrambling technology and the crystal-clear signal transmission of the RTS/TELEX systems on board, the Skandi Singapore dive support vessel is now equipped with what is described as "a professional communications solution with excellent audio quality."