COMPUTER Xios EyeSea Wreck Diver
Electronics have revolutionised navigation of ships, planes and even cars. However, GPS doesnt work under water, as H2O absorbs radio waves, so designers of electronic navigators for divers have turned instead to sound waves.
The idea of a sonic sounder that responds to a transmitter and indicates the way back to the boat anchor or shotline is not new. I tried one three or four years back called the Sonic Seeker.
It was not a resounding success, however, and fellow-passengers on a liveaboard enjoyed watching me having to hunt for the transmitter in the dark by the red light it emitted, after I had lost it during a day-time test. The Sonic Seeker might have been cheap, but Ive found more effective devices in Christmas crackers!
Then came the Uwatec Neverlost. It worked, but the beacon is so expensive that I would be reluctant to leave it unguarded, especially on a shotline. You never know who might be hanging about. The seeking unit is also very big (about the size of a good underwater lamp). While it worked perfectly, it tended to dominate the dive.
The new Xios EyeSea Wreck Diver is a more economical package and the seeker unit can be strapped to your wrist. Its about the same size as the earliest diving computers. Instead of having to scan round to get a signal, it provides the diver with a permanent LCD display, rather like an electronic compass. Barring interruptions, it always indicates the way back, even if that way is behind you, unless you block its view of the transmitter beacon.
A little anchor icon moves round a circle on the display. Line this up with the lubber line and youre on your way back. It also displays a calculated distance-to-beacon up to a kilometre! I didnt swim that far from the boat, but I guess it gives good warning if the boat leaves without you - as has been known to happen.
The lesser distances I swam seemed accurate enough, except on one dive during which I saw more than 600m displayed at a time when I could clearly see the beacon. Thats what I call good viz! It must have been caused by one of those anomalies one is always reading about.
You need to deploy the transmitter beacon sensibly. Hanging at about 15m proved perfect, but being nearer the surface cluttered the receiver/seeker with reflections from its underside. Being upside-down also renders it useless, and hang it too deep and underwater obstructions will block the sonic waves.
You must initiate the receiver/seeker to the beacon before diving. If a lot of you plan to use a single beacon, all your receiver/seekers must be initiated at once and left switched on until all the dives have been completed. The manual suggests placing the beacon and receivers/seekers in a bucket of water to do this, otherwise everyone has to hang off the boat with the units under water, which is not ideal.
You have to learn to fly on instruments. Its like when you first use a compass - you often cant believe what its telling you. Even the most experienced diver can get disorientated, so you have to trust the EyeSea or theres no point in having one.
I didnt much like the method of switching on the receiver unit by tightening the battery compartment. This seems to offer users the chance to flood the compartment, and after one obviously inadequate freshwater rinse I had to get the pliers on it to turn it on again.
The Xios EyeSea Wreck Diver with one transmitter beacon unit and one receiver/wrist unit costs £399. Additional wrist units cost£269.
  • Sea & Sea 01803 663012, www.dive-team.com

  • Divernet Divernet Divernet
    + You always know your way back
    + More economic that the Neverlost

    - Beacon is still vulnerable to dishonest divers on busy sites
    - Method of switching receiver unit on is suspect