COMPUTERScubapro Xtender
MANY PEOPLE NO LONGER WEAR WATCHES. If they want to know the time, they look at their mobile phones. Time-keeping has been relegated to a secondary function, and I bet John Harrison is turning in his grave.
John Harrison He was the 18th century fellow who won the prize for inventing the marine chronometer. Before then, time-keeping was done in a more relaxed fashion, and people were accustomed to missing the boat.
More recently, divers got into the habit of wearing their computers on their wrists, not so much for time-keeping as for stopping them getting misplaced. However, to do so might draw the unwelcome attention of other divers and precipitate an unwanted exchange about the size of your lobbies when you enter a pub for a quiet pint.
Suunto came up with the idea of a diving computer that could double as an everyday watch, and after a protracted interlude all the other computer manufacturers are now clambering aboard the bandwagon.
Scubapro/Uwatec has recently woken up to the fact that it is no longer alone in the marketplace, as it was in the late 80s, and has showered its dealers with a barrow-load of new products. The Scubapro Xtender is one of them, and its a computer that doubles as a watch.
Dont confuse this with the other Scubapro computers that hail from Uwatec in Switzerland. In a departure from the norm, Scubapro has dispensed with input from those who dive in Swiss lakes, and I was not surprised to discover that this model was made in Japan.
It looks like a typical Japanese digital watch. In fact, dare I say it, it looks very like the computer-watch made by Seiko and sold by Apeks as the Pulse. Unlike the Pulse, it is a single nitrox-mix computer.
I found the instruction manual very hard to follow, as I do other manuals of sophisticated electronic goods written by computer nerds in Japan. I resorted to doing what I thought I should with the four buttons provided, and managed to set the time and date; a dual time for another country; a nitrox mix of 32%; and the extra caution-factor available.
I considered this a personal triumph, especially as I never once jumped up out of my chair in exasperation while doing it.
The Scubapro Xtender has a pre-set ppO2 of 1.4 bar and, unusually for such a simple computer, it can be set to up to 100% O2.
Nitrogen-loading is indicated by a graphic that grows up one side of the display, while the oxygen-loading builds up along the opposite side of the watch-face. Thats for those who have trouble understanding numbers.
I was unable to find out who wrote the algorithm for this computer, but experience of computers from the same source in Japan tells me that it is as cautious as any.
It might not have fancy settings such as Deep Stops, but it will see you safely back to the surface, even after a dive with decompression stops.
I was surprised that it offered no safety-stop display in the 5-3m range, but I noted that it did hold you at 3m for longer than I would have expected from the time of the 3m deco-stop indicated.
In common with every other computer, this one enters Dive Mode as soon as you go diving. The display was easy to read, even for someone as optically challenged as me. You can download its data via a PC, but I understand that the software and interface cost extra.
As modern nitrox computers go, the Xtender is a fairly basic bit of kit, but it is a very wearable watch.
The Scubapro Xtender costs£299. An ice-blue womens version is also to be launched.
  • Scubapro UK 01256 812636,

  • Divernet
    + Single nitrox-mix computer in a watch format

    - Basic computer with non user-replaceable battery
    - More expensive than an Aladin Prime when PC accessories are included