Questions about AI Transmitter

[BoltSnap]

I've been diving since I was 16 years old.

Two years ago???

 

[dmaziuk]

Two years ago???

Taking the lower end of Craig's stated 1,000-2,500 dives, that's 1000/(2*365) which makes one dive every day and a 2nd dive every other day for the last two years. No holidays, no days off, no exceptions.

 

[Joneill]

I had an Aeirs ai computer. 2-3 of them any way. and I believe they turn on at 50 psi. The real question for me is . Is the same depth sensor used to shut down or is it a separate sensor. If separate then you can not use the AI INPUT to say when it shuts off. All and I mean ALL my AI units after a year or there abouts got a 300# error in them. That was proved by using an independant tank gage. In that case one would be inclined to think that it turned on at 350 psi and not 50 psi. My Ai errors varied from being at the high end low end or over all. The one most noticed is on the high end when you know you have 3000 psi gage and the ai reads 2700. I don't use AI any more because of that and the cost of refurbing them. 100$ or more each time. I hope they have improved over the years. The Aeris and Oceanic are the same I think. Also when you vent the reg you have to do it again in a few minutes becasue you will get 50# again and it will start transmitting. All you have to do is remove the reg and listen to the air slowly drain from it through the regs tank fitting. I ultimately had use an spg with the AI.

Once I turn off the tank and vent the reg for surface interval, it does not build back up to 50# again - it goes to 0 and then no signal - it does not start transmitting again as there is zero pressure!

I have used 2 transmitters (Teric and Perdix AI) and they always read within 5-10 psi of each other. My old SPG always showed 100-150 psi more than the AI. That SPG broke (dropped it) in the middle of my last trip in Feb and the replacement SPG pretty much matches the AI - so I suspect my old SPG was a little off calibration. I suspect AI tech is more accurate and precise as well?

 

[NAM001]

Once I turn off the tank and vent the reg for surface interval, it does not build back up to 50# again - it goes to 0 and then no signal - it does not start transmitting again as there is zero pressure!

I have used 2 transmitters (Teric and Perdix AI) and they always read within 5-10 psi of each other. My old SPG always showed 100-150 psi more than the AI. That SPG broke (dropped it) in the middle of my last trip in Feb and the replacement SPG pretty much matches the AI - so I suspect my old SPG was a little off calibration. I suspect AI tech is more accurate and precise as well?

My mk25's do not give me the same indications as yours does. I remove them and put my finger over the regs hp tank port and feel the pressure build up. I can totally vent it like you are suggesting and in a few minutes it comes back on again and I then have to purge the reg again to deplete remaining air. I can purge the reg remove the reg form the tank put on the reg cap and then go back in a couple minutes and purge more air, not a lot, but air just the same.

 

[Joneill]

My mk25's do not give me the same indications as yours does. I remove them and put my finger over the regs hp tank port and feel the pressure build up. I can totally vent it like you are suggesting and in a few minutes it comes back on again and I then have to purge the reg again to deplete remaining air. I can purge the reg remove the reg form the tank put on the reg cap and then go back in a couple minutes and purge more air, not a lot, but air just the same.

That's interesting - mine is an Atomic T3 and once it's purged, it's completely unpressurized (actually the seat saver orifice pulls back and stays slightly open, so all the air bleeds out).

 

[tursiops]

My mk25's do not give me the same indications as yours does. I remove them and put my finger over the regs hp tank port and feel the pressure build up. I can totally vent it like you are suggesting and in a few minutes it comes back on again and I then have to purge the reg again to deplete remaining air. I can purge the reg remove the reg form the tank put on the reg cap and then go back in a couple minutes and purge more air, not a lot, but air just the same.

Where is the air coming from? Is it being stored in your SPG hose?

 

[NAM001]

Where is the air coming from? Is it being stored in your SPG hose?

I have no idea some where in the stage one body itself. That would be a reasonable source for it but the gage goes to zero when I vent it or take it off the tank. Im sure the lp purge will vent much faster than the hp air will back feed from the spg to teh first stage.

 

[scubadada]

Two years ago???

Don't I wish, 49 years ago

 

[BoltSnap]

I have used 2 transmitters (Teric and Perdix AI)

One transmitter for Perdix and another one for the Teric??? Why? Cant the two computers work off the same transmitter?

 

[Joneill]

One transmitter for Perdix and another one for the Teric??? Why? Cant the two computers work off the same transmitter?

Sure - and 2 computers can use 2 transmitters too. I set that up instead of a transmitter and an SPG. More streamlined redundancy.