Opinions on Luna problem

[soltari675]

I am having a weird problem with my Galileo Luna computer with air integration. I was diving with it Monday in the ocean with no problems. Today though, I went diving to three different locations, all of which were overhead environments. This was the first time I have done any sort of cavern diving. My problem is as soon as I would get under an overhead, my computer would lose the signal from the transmitter. I couldn't see my psi. The rest of the computer worked fine. If I came out of the cavern, I got the signal back. While in the cavern, I tried holding my computer on my shoulder near the transmitter with no luck. Near the entrance to the cavern, it would work for a few moments. I don't quite understand why going into a cavern would interfere at 3 separate sites?

 

[jh_MacLeod]

I am having a weird problem with my Galileo Luna computer with air integration. I was diving with it Monday in the ocean with no problems. Today though, I went diving to three different locations, all of which were overhead environments. This was the first time I have done any sort of cavern diving. My problem is as soon as I would get under an overhead, my computer would lose the signal from the transmitter. I couldn't see my psi. The rest of the computer worked fine. If I came out of the cavern, I got the signal back. While in the cavern, I tried holding my computer on my shoulder near the transmitter with no luck. Near the entrance to the cavern, it would work for a few moments. I don't quite understand why going into a cavern would interfere at 3 separate sites?

Well obviously I have no way of really knowing the cause of your problem, but since I do know a little something about RF, I'll offer a few thoughts. The first thing to check is your power level on your transmitter battery. If the battery is weak, it's transmitted signal may be weak, and thus the effects of any attenuation caused by the cavern would be more obvious. But, if we assume that your battery is fine, then the only other logical conclusion I would come to from the symptoms you describe is that there is probably something in the rock of the caverns in the area where you're diving that is having a dramatic effect on the strength or pattern of your transmitter's RF field. You don't say what region of the country these 3 dives took place, but geological formations in some areas may contain high amounts of iron, other metals, or even magnetic elements which could have a strong effect on RF fields. Beyond that, I would only suggest that you try a different transmitter in the same conditions and see if you get the same or different results. Good luck solving the mystery.

 

[DA Aquamaster]

A couple thoughts...

Back in the day, divers I knew who used air integrated wrist computers often used a 6" High pressure hose to get the transmitter out away from the reg/back of the head.

I also noted that they tended to use the computer on the same side as the transmitter, so with an SPG on the left side, you need to carry the transmitter on the right side of the reg with the computer on the right wrist.

But lets be honest here...you are now doing overhead environment diving. I don't know any cave divers who actually trust the air integrated functions of a wrist computer, so a "back up" SPG is mandatory (for reasons that you have already discovered).

And, if you have the now manadatory - and very reliable - SPG along already, you don't really need the wireless air integration information so it makes more sense just to leave the transmitter at home.

I do have a Luna that I will use on cave dives, mostly for the excellent electronic compass, log and bookmark features, but I have never even owned a transmitter for it.

 

[Jax]

The OP asks a question about his computer system, and instead of answering it, you have to say, "you [-]shouldn't use[/-] don't need it." Seriously?


Solitari, I have a couple of AI Uwatecs. Do you know what the 'born date' is for your Luna? My new SmartTec was actually a year old when I purchased it, and once the battery is in, it "seems to" be using a little power continuously.

I agree with the possible weak signal transmission. However, make sure you replace the O-ring, use silicone lube, and tighten the screws carefully. If you do flood it, it cannot be repaired (says ScubaPro). However, when mine flooded, they (through the dealer) offered me a refurbished one for 1/2 price. Had to ship the flooded one in, of course.

Good luck!

 

[RickPeck]

The OP asks a question about his computer system, and instead of answering it, you have to say, "you shouldn't use it." Seriously?

Read it again. He didn't say "don't use it." That's your take on the post.

He suggested that the OP not depend on a wireless signal and use an SPG, eliminating the need for the TRANSMITTER. Not a bad suggestion at all. If you want to leave the transmitter on, no harm done. Other than a leak point if you break it off your 1st stage.

Rick

 

[Jax]

Read it again. He didn't say "don't use it." That's your take on the post.

He suggested that the OP not depend on a wireless signal and use an SPG, eliminating the need for the TRANSMITTER. Not a bad suggestion at all. If you want to leave the transmitter on, no harm done. Other than a leak point if you break it off your 1st stage.

Rick

You're so right. Fixed it for you.

For the OP - if you happen to break the transmitter, as long as you do not break the stainless steel part that screws into the first stage, you will not have a leak. If you break the stainless steel part, you have so much more to worry about . .

 

[DA Aquamaster]

Read it again. He didn't say "don't use it." That's your take on the post.

He suggested that the OP not depend on a wireless signal and use an SPG, eliminating the need for the TRANSMITTER. Not a bad suggestion at all. If you want to leave the transmitter on, no harm done. Other than a leak point if you break it off your 1st stage.

Rick

Right.

Jax, read the OP's post again. She clearly articulates a problem related directly to using wireless AI in technical diving and he clearly indicates she is transitioning to cavern/cave/overhead diving.

Granted, Cavern is designed to be done with a more or less OW configuration, but if the OP is headed down the technical diving path, things like wireless AI transmitters are going to get left on a shelf in the garage.

Despite that, I also gave her a couple suggestions to improve reception based on divers who had similar issues around rocks with lots of iron in them.

Now, I could feed her full of BS about how great wireless AI is in technical diving, but the reality is that the quickest and most effective solution relative to the diving she is now doing, or at least considering doing, is to get an SPG and consider dumping the wireless air integration feature of the Luna as it adds relaibility issues that are not consistent with the demands of technical diving.

If you re-read my post, you'll note that I use a Luna. It has some great features that are consistent with technical diving and it works well in conjuction with a Predator as each computer offers something the other does not. And when the Trimix upgrade for the Luna/Sol is out of beta and generally available, it will be a solid choice for trimix diving.

As it is now, with the PMG upgrade a Luna is a fine multigas nitrox computer for AN/DP, Cavern, Intro to Cave, and Full Cave at less than Trimix depths, or in gauge mode.

 

[Jax]

Or, you could not go off topic at all. People ask questions for an answer, not to be lectured about their gear. He didn't ask if anyone thought a transmitter was okay for an overhead environment.

It's like asking a question about what size pony, and having someone come back and question why you think you need one.

Why can't the OP be given the respect of assuming he made his own decisions on his equipment, without someone interrupting his thread and saying he doesn't need it?

 

[soltari675]

Easy guys I am a she by the way. Thanks for the information from all of you. I did have a dive shop nearby replace the battery. I bought the computer last August, but like you said, who knows how long they had it before I got it. I used it in an ocean environment today without any hiccups at all. I will be in some overhead environments tomorrow and will see if it fixed it. I'll bring an SPG as a backup just in case.

As for continuing to use the transmitter. I think I will. I don't plan to do very many cavern dives like this. This trip was all about trying new kinds of diving like ocean and caverns. It's ok. I like it, but I don't think I will do a lot of it. I will probably find myself doing more wrecks and taking pictures of fish. But I did learn to get a backup just in case something goes wrong with my transmitter again.

I am in central Florida by the way. I believe the divemaster at the first site said it was a lot of limestone. Didn't sound like it would interfere, but I don't know much about the rocks. I'll see tomorrow if the new battery fixes it all. Thanks again for the comments.

 

[jh_MacLeod]

I did have a dive shop nearby replace the battery. I bought the computer last August, but like you said, who knows how long they had it before I got it. I used it in an ocean environment today without any hiccups at all. I will be in some overhead environments tomorrow and will see if it fixed it. I'll bring an SPG as a backup just in case.

I am in central Florida by the way. I believe the divemaster at the first site said it was a lot of limestone. Didn't sound like it would interfere, but I don't know much about the rocks. I'll see tomorrow if the new battery fixes it all. Thanks again for the comments.

I agree, limestone shouldn't be a factor. I thought perhaps you were doing these dives in Missouri (your profile home) or somewhere there might be lots of granite. Battery is the likely culprit.

Besides the convenience of having the air guage on my arm, I like AI for dive analysis on the computer later. It's nice to be able to see your consumption rates at different depths or in different situations (exertion, current, etc.)