Re: Diving with Handheld GPS & VHF Radio - Red Sea Debacle at the weekend

Richard Faulkner wrote:
> Would it be possible to dive with a both handheld VHF radio and GPS,
> protected by those waterproof plastic packet things that you can buy
-
Even better, you can get them integrated into one unit - so that you
can use DSC and stuff to send your location to the coastguard along
with your Mayday. The two technologies go hand in hand so it seems to
make sense.

"Mayday, mayday, mayday - this is ######, ######, ###### - at ...
bugger where am I?"

> i.e. would they survive the depth/water pressure?
They probably wouldn't survive the pressure.
I think you'd need to put them in a box/canister that would, maintain
1ata pressure.

> And would this have helped the diver who were mislaid at the weekend?
Yep.

I expect a few people will come along now and tell you to get an EPIRB
because the range of a VHF radio is more limited - what they forget is
that if you have an EPIRB you've got to get a signal to a helicopter
looking for you, whereas with a VHF radio you only need to manage to
reach your own dive boat (or any other boat).
They'll also say that you'll have problems with range because you'll be
in the water (same with EPIRB), but since the maximum range from the
line of sight is proportional to the sum of the square roots of the
heights (may be wrong about that - just did the calculation on the back
of an envelope), and the coastguard will use recievers much higher up
than you can manage in a RIB, you don't lose much range.

I've not done this myself though - it's just an idea I'm playing with
in my head.

Alun Harford

<alunharford@yahoo.com> wrote

> Even better, you can get them integrated into one unit - so that you
> can use DSC and stuff to send your location to the coastguard along
> with your Mayday. The two technologies go hand in hand so it seems to
> make sense.

If you're looking for rescue assistance, it's hard to beat a pressure proof
EPIRB. ACR makes one as well as a directional receiver to allow dive boats
to find their missing divers more easily.

Lee