Shearwater Owners with AI, do you dive with a SPG?

[Seaweed Doc]

I use both, for two reasons.

1. I'm a Luddite that likes teaching things. Now look up Luddite and consider yourself taught. (More seriously, I trust brass-and-glass more than AI. The only issues I've had with AI were user error, but I'm user that occasionally errs.)

2. I'm teaching SCUBA. Occasionally a student's reg set up as a leak at the gauges I can't quickly fix. I can transfer my SPG to them, loan them my backup computer, and put a plug in the HP port where the SPG plugged in to my first stage.

 

[NAUI Wowie]

I've had my an AI Shearwater computer, for a few years now (I'm knocking on wood), but have not really had any issues and am really considering ditching my SPG. I really like a very minimalistic kit and would love to get rid of it. How many Shearwater users have ditched the SPG?

Thanks,

Pete

Gone from day 1. not needed.

 

[DreadnoughtNH]

AI + SPG for me. Over my years on and in the ocean, I've had enough electronics go wrong on me for me to solely rely on one piece of mission critical gear. My Perdix AI has never acted up, but at 100' down I like some redundancy.

 

[Tigerpaw]

Personally I like redundancy, so I dive with both and also check both of them.

 

[OhioDivingDude]

Yes I dive an SPG when/if I use my transmitter.

I find the transmitter is frequently dead (out of battery) so I don't rely on it. If I leave it pressurized it stays on and drains the battery. Since I leave my doubles regs assembled on the tanks this happens quite often.

you leave your kit pressurized? doesn't seem like a good practice over periods of time.

 

[OTF]

you leave your kit pressurized? doesn't seem like a good practice over periods of time.

No, but if a valve gets bumped on the boat or whatever and I forget to completely purge the reg then the pressure keeps the transmitter on and kills the battery.

 

[NAUI Wowie]

Why would you end your dive if the AI fails, but you still have a SPG?

AI is a function of the dive computer. If your dive computer fails its a good idea to call the dive. You will know before a dive if you have a low battery so any failure is likely the computer.

 

[Joneill]

AI is a function of the dive computer. If your dive computer fails its a good idea to call the dive. You will know before a dive if you have a low battery so any failure is likely the computer.

Not true at all! The DC will continue to work just fine if your transmitter stops working for any reason - it just won’t display tank pressure or other AI data.

 

[Wibble]

AI is a function of the dive computer. If your dive computer fails its a good idea to call the dive. You will know before a dive if you have a low battery so any failure is likely the computer.

There's a battery in the dive computer. It should warn you if it's too depleted to last the dive.

There's also a battery in the AI transmitter(s). If that battery is dead, as will happen if you leave it switched on under pressure, then you'll need to replace it. If the battery is low, it should "warn" your dive computer that the battery is low (this happens with Shearwater).

SAFT batteries last a lot longer than most others. BUT SAFT batteries will suddenly drop their voltage at the end of their life.

If you're using Shearwater computers, the batteries can be easily replaced in situ. 30 seconds to unscrew the battery compartment with a coin and replace the battery. Not the case with Suunto who seem to think you'll take it to a local dive shop for a gouging as you need to remove the transmitter and unscrew some screws...


My experience with my two AI transmitters on my rebreather are that it seems to be an annual thing that at the end of the AI battery, the Diluent transmitter will probably not work when turning on the gas if the unit's been unused for a couple of weeks. Not a problem as I just replace both batteries at the same time and that's that for another year.

The Perdix & Petrel I monitor the voltage as part of my build process and when it starts to fall I'll simply replace the battery. I've seen a low battery warning once on a dive; the computer worked for the whole dive.

 

[Capt Jim Wyatt]

SAFT batteries last a lot longer than most others.

The problem is getting genuine SAFT batteries....seems that its just as likely to get cheap/useless chinese knockoffs as the real thing. What source do you use for Saft? I have a Predator that only uses SAFT and I'd like to power it up again.