Christopher Cartwright spends his time recording wildlife footage on video for potential sale to TV producers. He works mainly with sharks and for this has found the long dive duration possible with the Buddy Inspiration closed-circuit rebreather invaluable. I met him while he was working in French Polynesia.
     I too was intending to use an Inspiration, and had arrived equipped with the latest version of Kevin Gurrs VR3 computer to use alongside it.
     The VR3 is unlike any other diving computer I have seen. It looks like something salvaged from the command centre of a battleship. It is well-loved by one group of technical divers but disliked by another, those who have found it to be unreliable.
     It certainly looks like the only computer a diver would ever need, with options for either open- or closed-circuit use, and the possibility of switching through 10 different gases including those with helium in the mix, throughout the most complex technical open-circuit dive.
     Christopher, seeing that I had the latest VR3 with the improved cover for its battery compartment, told me some horror stories about his own.
     I had been diving, recording shark action, in Tikehau and I had been at 27m for 197 minutes, he said. I had noted that my CNS oxygen limit was getting near to maximum, which meant that it was time for me to end the dive. Then the display froze. It was just like Windows 98!
     I asked him what he did next. Luckily, I knew the dive well and I was diving with air as a diluent. It was all very familiar, so I did the stops I knew that I would normally do. Everything seemed to work out OK.
     Did he still use the VR3 Its the only computer I own, so I still use it, but it freezes all the time now. It also stops without warning that the battery is low. For example, the other day it froze on me while I was 60m deep in the Tiputa Pass in Rangiroa. I simply cant rely on it to complete a long dive.
     In the light of this account, I decided to use the VR3 alongside another computer. However, I first had to familiarise myself with this very complicated item.
     I had downloaded the latest version of the manual and, with some long evenings aboard the Tahiti Aggressor ahead, was confident that I would have time to be thoroughly familiar with the VR3 before the cruise was over, and before changing over to my own Inspiration closed-circuit rebreather. I was to dive in the meantime with open-circuit scuba and another computer.
     The first evening aboard, I sat down with the VR3, handbook at the ready. It was set for a date in the last century, so I decided to change it. My first failure. I couldnt get the instrument to remember the new date until I had tried many, many times.
     The VR3 is set up with two buttons. You push one or the other or both, either a long push or a quick push, to get the desired result. After several rotations of the display (long pushes on two buttons) I managed to get it to confirm that it was already set to CCR use and with a ppO2 of 1.3 bar. But this moment of triumph was short-lived. The left button released itself from the unit and fired itself across the saloon, closely followed by its spring.
     So, game over. No VR3 for me to use on that trip. I didnt bother to ask to borrow Christophers either! I sent mine back to Kevin Gurr at Delta P Technology as soon I returned to the UK.
     Kevin sent me back the latest version, complete with the port for a CCR fourth-cell on one side. He also sent me the tool needed to open the battery compartment. Lucky I had it! I found that I needed to take out the battery and start again before I was able to get it to remember the current date and time.
     I started by asking other VR3 users in the UK to help me set it up, and was astounded that so few of them knew how to use their own. Invariably they had a friend with the knowledge. So I set off again on a dive trip with the daunting prospect of wading through the instructions.
     The VR3 uses the same modified Buhlmann ZH-L16 algorithm as ProPlanner, Kevins well-used software for planning technical dives using a PC. It promises to provide every bit of information a diver could possibly need. As such, it is necessarily complex.
     I went to the Cortez Club at La Paz as one of four divers using Prism Topaz closed-circuit rebreathers. I asked fellow Prism-diver Andy, who had his own VR3, to set mine up for me. He confessed that he had bought his secondhand and already configured for use with a CCR with a ppO2 of 1.3 bar. He could read it but didnt know how to set it up.
     I did several long dives (with a Buddy Nexus on my wrist) looking over his shoulder at his VR3 while my own sat unused back on shore.
     The VR3 I had was not configured for CCR, but I had a PIN number to enter into its memory that would allow me to do that.
     I had to bite the bullet. Entering this hexadecimal number, composed of both figures and letters of the alphabet, enabled me to start getting inside the mind of the inventor, whoever Kevins backroom-boy is.
     A short push on both in fact turned out to be a quick push on the left followed, without break, by a quick push on the right.
     Once I had this knack, it made all the difference. I was finally ready to use this VR3, still complete with its buttons, and with air as a diluent to a fixed ppO2 of 1.3 bar, but only after a remarkable 90 minutes of button-pushing.
     I got the impression that this computer will do anything you want once you find out how to make it work. That might take some people a long time. It did me.
     The display under water looked straightforward enough, with depth and time, no-stop time, stop depth, stop time and total ascent time all clearly displayed.
     When you reach a stop, there is an animated graphic of a little diver on a line which indicates the zone in which it is safe to ascend during continuous decompression. If you pass a stop ceiling, a down arrow gives you 60 seconds, counted down, to get back to the right depth.
     The VR3 requires deep stops, which are quite convenient on a multi-level dive on a coral reef but might take some nerve, as total deco-time begins to mount, while hanging on a shotline. Of course, to see all this I had to use the computer in open-circuit mode. My CCR dives were all no-stop. So, more button-pushing.
     By my third dive trip, this time an open-circuit expedition to the Red Sea, I seemed to have got the hang of it. However, on several occasions a clock display with the current time appeared.
     I confess that I dont know what made this suddenly show up. There seems to be layer upon layer of information lurking within this computer!
     I know that I have hardly scratched the surface of what this instrument can do. The owner will need to wade through the poorly written instruction manual to find out. I guess that this is aimed at those for whom using the kit is the principal reason for going diving. If you need a computer to monitor a dive for which there is another purpose, such as filming wildlife, you might well not have the patience to bother getting to grips with setting it up.
     But writing as one who made it through the long dark tunnel of learning about the VR3, I can now say that its excellent!
The VR3 can cost up to £1000, according to the specification made accessible. As you pay more, you get the hexadecimal PIN number supplied to access what you need.
  • Delta P Technology 01202 624478, www.vr3.co.uk

  • Divernet Divernet
    + For computer enthusiasts
    + The only computer you will ever need

    - Daunting to set up for use
    - Not for technophobes or the impatient