Im getting old, and the world has changed. In the days when most divers made their own wetsuits, people would try to rip my computer off my arm, because I was a rich git who obviously had more money than sense.
     Today I often see people wearing twin VR3s and mega-expensive rebreathers, so I suppose the grand that a Suunto D9 might set you back is comparatively small beer.
     The D9 is the new top-of-the-range nitrox computer from Suunto. It is made of titanium, has the dimensions of a (large) watch and is gas-integrated via a radio transmitter that looks a lot like that of the sibling Vytec.
     The computer can be switched during the dive through three previously programmed nitrox mixes. It is primarily aimed at the diver who wants to go deep on, say, air, yet speed up his deco by switching to, say, nitrox 32 and then an even richer mix of nitrox in the shallows.
     It also has a built-in electronic compass which will point to your chosen route, or a steel wreck, or the mass of steel tanks that you might be carrying.
     Yes, using any compass is fraught with difficulty if you dont accept its limitations. I hear of Inspiration rebreather users strapping compasses onto their handsets, not realising the effects of those magnetic switches.
     Once you have got the hang of what the four buttons do, and the differences between a short push and a long one, this instrument is fairly intuitive to use. It does not, however, follow the same format as the Suunto Stinger, so I did get a bit confused at first.
     You can choose either the RGBM100 algorithm or the more aggressive RGBM50. You can set degrees of personal caution.
     You can choose whether to have deep stops displayed, and their duration, or whether to have the 5m safety stop displayed instead. You can set your main nitrox mix, and any two deco mixes you might want to use. Or you can simply use gauge mode.
     The D9 is a calendar watch with stop-watch, has a self-illuminated display, and you can set various audible alarms.
     I asked Nico Ghersinisch, dive-guide from mv Sea Hunter, to use it for a week while I was diving with him in Cocos. He told me he found it very logical to use, with its clear and easy-to-read display.
     The alarms were always very discreet, he felt, which spares a dive guide unnecessary embarrassment. They seemed more sensitive than the older computer he was using alongside the D9, and a simple push on a button turned them off under water once his attention had been drawn to whatever the computer was trying to tell him. The downside was that he slept through the alarm when he used the D9 as an alarm-clock.
     In Cocos, upwellings mix cold water from the depths with warm water at the surface. There are many thermoclines. Nico commented that the temperature display was very precise and much quicker to change with water temperatures than any other computer he had ever used.
     It paired instantly with its transmitter, but the duties of a dive-guide are such that Nico often got his kit ready on the pick-up skiff, then had to reboard the main vessel for some task. So the computer on his arm would lose the transmitter signal during the intervening period.
     However, he found that, provided he made a pressure change to his tank immediately before diving by, for example, taking a couple of breaths from his regulator, the pairing was resurrected.
     This was certainly an improvement over what has been available before, and you have the option to change a transmitter code if you find that someone else nearby is using the computers first choice.
     During the dive, the D9 displays all the deco information you need. However, querying if he had it set up correctly, Nico found that he had to press a button to see the ongoing dive duration instead of the water temperature. He felt this was the wrong way around.
     In fact, thats a setting-up option. You can choose to have either one of those settings, current ppO2 or current OLF (Oxygen Limit Fraction) as a primary display, with the others as secondary. Most will opt for dive duration as their primary choice.
     Logbook mode is fantastic, because with the usual information the D9 can also display a graphic of your dive profile. You can examine the profile minute by minute by using the Up and Down buttons of the computer. I can imagine people passing long surface intervals playing with this feature.
     The compass function is called up by pressing the Select button for two seconds or more. Its a cinch to use. You can mark a course and it tells you whether to swim left or right to follow it. It displays bearings as well as the usual N, S, E and W and so on.
     So, price apart, whats wrong with the Suunto D9 Well, its a bit ugly for a watch. Titanium is too garish to look nice as jewellery. Also, I noticed another early user wearing a large Band-Aid on his wrist under the buckle. Its probably a bit too manly for some! Nico experienced no such problem after having it permanently on his wrist for a week.
The Suunto D9 with interface and Dive Manager costs £750 - with the optional transmitter it comes to £1050.
  • Suunto Diving & Marine UK 01420 587272,

  • Divernet
    up to three separate nitrox mixes can be indicated
    Log mode gives a profile of the dive-section by section
    electronic compass mode
    surface mode
    + Everything you need in a nitrox computer

    - A bit ugly for a watch