Quantum - Is it a random number generator?

[davesnapeuk]

I have recently under taken 2 dives with buddies who were both diving on Suunto computers (D9 and Vytec).
Our dive consisted of a leasirely drop to 36m where we stayed there for a good few minutes and entered deco. During this dive my Quantum has logged a 39.3m depth whilst my buddies, both approx 1-2m below me, both logged 36m dives on their Suunto's. I can understand that the different dive models have an effect on the required deco stop (my Apeks Quantum is set to 0% safety whilst both Suunto buddies are set to 50% RGBM) but how on earth did my Quantum decide that for a split second I was 3m below my buddies?

I can only assume that my Quantum has become a random number generator for depth around the moment that it has to think about me going into deco.

Has anyone had a similar problem? I remember a previous diver on a quantum entering deco who had a random deco time appear on his computer.

[NeilP]

I had one like that once.
It gave a load of wierd readings.
Send it back to Apeks and they will send you a brand new one.

[shog69]

Salt or Fresh Water ?. Can't remember which way round but my friend has one and it reads a lower depth than my Stinger depending if we dive in Salt or Fresh water.

[philmed]

Salt or Fresh Water ?. Can't remember which way round but my friend has one and it reads a lower depth than my Stinger depending if we dive in Salt or Fresh water.

In fresh water some computers read shallower than actual depth because they are calibrated for sea water. The manual for my wife's Vyper 2 says it is calibrated for seawater and will read 3% smaller depth in fresh water.
My old clockwork Mares Guardian on the other hand has automatic saltwater to freshwater calibration so always reads the actual depth.
I don't know how the Quantum is calibrated but it should say in the manual.
Phil

[Pubbloke]

There is an option on the quantum for salt or fresh that you set before the dive, you could have had it in the wrong mode.

[NeilP]

There were some a few years ago that were always going wrong.

The one I had was one of those I think - used to do things like jump from 10 minutes no deco time upto 15 minutes deco. And freeze.


Good job it was a backup.