I just bought the VT3, but I'm thinking about returning it. The FO2 setting for transmitters 2 and 3 have to be set higher than the FO2 for transmitter 1 (and 2). Additionally, on transmitter 1 the FO2 for dive 2 and later, must be equal to or greater than that for dive 1. That means that I can't make a NITROX dive followed by an air dive. Has anyone found a work-around for this feature? Does anyone know why Oceanic included this feature on the VT3? Thanks!
Not being able to change FO2 to a lesser number after a dive is absolutely incorrect. I have dove a leaner mix on subsequent dives. Just remember, you have to wait until 10 min after your last dive before you can change
ANY settings. The computer considers any dives made within the 10 min period a continuation of your existing dive. After 10 min you can re-set any of the FO2's, even back to 21% if you want.
I do agree that having to set GAS2 and GAS3 to the same or richer mixes than GAS1 is a limitation, but the intent is you are supposed to switch to richer gasses for deco. For me I might be diving a single with Nitrox, but have an air filled pony bottle and if I had to switch, I would like the computer to calculate my nitrogen loading. However, there is a workaround to this limitation.
Let's assume I have EAN32 in my main tank and air in my pony bottle.
You set GAS1 to Air, and GAS2 to your EAN32. If you are using a transmitter, make sure you punch in your main transmitter S/N to GAS2 instead of GAS1.
The computer automatically makes you start out with GAS1, but after you desend 5 feet and the computer goes into normal dive mode, immediatly do a gas switch to GAS2 (which is your richer EAN32 main tank), and simply dive on GAS2. If you had to later switch to your bail out air mix, you just switch back to GAS1. It is working the gas switches backwards.