First time subsurace usage surprises

[Lutz Vieweg]

On 08/02/2012 12:46 AM, Linus Torvalds wrote:
> There seems to be this crazy tech diver community that thinks wireless
> air is a bad idea. They're wrong.

That is very true!

> Sure, you want to have a gauge for backup

If you consider a single mechanical gauge safe enough, then a single
wireless sensor is at least as safe.

A mechanical gauge always "displays" a value, even if that value
is total bogus because something inside is corroded or broken.

Once when I dived in Mexico, an inexperienced guest from Poland
actually believed his (rented) mechanical gauge when it indicated
a nearly full tank still after 30 minutes. He suddenly went out of air,
and performed some less-than-healthy ascend using the octopus of
another diver. The gauge stll displayed ~190 bars after it was detached
from the tank.

Using a wireless pressure measurement, chances of being displayed
a total bogus value are smaller - the pressure sensor itself it
practically "solid state", and if the electronics of either the
sender or receiver fail, you will most likely see no value or some
sort of error indication. And in that case, you can still end your
dive doing a very normal ascent.

Also, without wireless transmission, there is yet another hose
that adds some risk of its own (it can leak, it can get entangled etc.).

> Sad. Because HW is so close in many other respects, and I love the
> open-source side of it.

Apart from no wireless measurement, for me it is also too bulky.
It's an important feature of a DC to me that I can wear it like
a watch - and look at it without having to take the hand it is attached
to from the camera.

Regards,

Lutz Vieweg