What is your guys' opinion on transmitters in a system. I feel there's no place for it but I have a buddy who is hell bent on they will never fail.
Printable View
What is your guys' opinion on transmitters in a system. I feel there's no place for it but I have a buddy who is hell bent on they will never fail.
I have had problems more than once on a Suunto computer that I used to use for OW only, I won't use them on anything now. I've never had my analog pressure gauge fail during a dive.
Sent from my iPhone using Tapatalk
This discussion comes up frequently, and I think a large majority agree they don't belong in cave diving. We have gotten more technology dependent in cave diving,but somethings have a higher failure rate, and their failure can be less forgiving than in open water
Has your buddy never owned a car, a house, a computer, a cell phone, or any other artifact of human endeavor?Quote:
Originally Posted by TaylorP
A couple of thoughts:
1) Everything fails eventually.
2) Time until failure and mean time between failures are both inversely proportional to complexity.
Complex electronic things are more likely to fail during a dive than simple mechanical things. And electronic radio transmitter SPG's are an example of something designed specifically to transfer money from the pocket of the diver to the pockets of the manufacturer, distributor, and retailer. There is no other conceivable reason for the existence of such a thing. Tell your buddy to buy a regular old fashioned SPG and spend the money he's saved on something worth having, such as bacon.
I have not had enough coffee yet this morning and am still cranky. Can you tell? :)
Mike
I got a good kick out of it!Quote:
Originally Posted by MORGAN
We tried talking to him last night at dinner and he just would not listen to a word anyone had to say about it. He's strictly CCR, will not dive oc. I don't think he realizes that when we're diving a mixed team we don't have the time he does. What's one way I can bring it up to him to where he realizes that it is just another failure point?
Is he diving CCR because he's doing dives that require a rebreather, or is he using a rebreather to do dives that could be done OC because he enjoys using complex equipment? If the latter, than he's an incurable technophile and gearhead and thus impervious to logic. That doesn't make him a bad person... :)
I have to plead partially guilty to those tendencies myself - in all aspects of my life outside of work I'm a low tech Luddite keep it simple guy. But at work I'm a critical care nurse at a university teaching hospital and love numbers and waveforms and digital displays. The more blinking lights and machines that go "ping" the better!
if he dives CCR and has them on dil and O2 I have no problem with it, and actually am surprised CCR's haven't moved to wired AI with the sensor in the head and the regs connected to it with controller displaying pressure. With the current generation out there I actually see no issue with them. On sidemount, put a button gauge on the top so you can check pressure without the computer at the surface predive if you want, but if you have a transmitter fail, it's just like any other failure underwater, turn the dive. It's not life ending if you don't know your pressure, you aren't going to lose any gas for your exit. With some of the older transmitters that were prone to dropping connections and had trouble syncing I get it, we were ahead of the technology, but if Shearwater came out with an AI option, I would likely try it. Going to try to convince Seabear to send a set around for some of the cave divers to try on our sidemount rigs and see if it is a legitimate option.
I do think it's the way of the future, but its too cost prohibitive on the newer transmitters right now to justify buying in with the bugs they still seem to be ironing out.
No, he's a fantastic guy I'm very glad to have him as a dive buddy. He has a smaller frame, almost 0 body fat so he gets cold easy. He enjoys the warm gas and how light they are and all that, I just see a transmitter getting knocked off of his bailout and him losing his saving grace. I'll suggest the button gauge, they're cheap enough to slap a few on!Quote:
Originally Posted by MORGAN
Which shouldn't be an issue when swimming back and forth from Olsen or when exploring the depths of the horseshoe circuit.Quote:
Originally Posted by tbone1004
On the other hand when you're 70 minutes from the exit or a stage tank, you won't want half of your gas to fade away because one unnecessary component of your gear blew an o-ring.
SPG's are currently the simplest and most reliable form of gauging the pressure, why add additional failure points?
if you have transmitter straight on the first stage and a button gauge it should actually be less O-rings. Button gauges use the same single O-ring as a port plug, and the transmitters if not on a hose extension should be the same single o-ring on the first stage.
Failure points for air leak I don't buy, failure due to batteries sure, but that's not catastrophic, just means you have to turn
I have been using an Oceanic Data Trans Plus since 1997, for all of my open water dives and some of my cave dives. I have had zero transmitter failures. The only reason I don't use it for cave dives any more is it is a one-gas computer.
I worry about the transmitters also. I believe that if you will just line the inside of your hood with tin foil, you will be safe.
Does anyone have experience with the Liquivision Lynx? My understanding is that it has now a sidemount mode where you can monitor both tanks simultaneously on the main screen. Does that work well? And, do you notice the transmitters under your armpits at all? It sounds like a neat concept, but I'd like to hear from someone who is actually using it. And I would keep the analog gauges as backup, for sure.
My big question is: Who is having such a hard time reading SPGs that they can justify $1k+ on transmitters? If reading your SPG is too much task loading....maybe diving isn't for you.....
I have not heard of any failures with them, and quite frankly SPGs get stuck often enough that they're far from perfect either. If you can afford them, I don't really see a lot of harm in using them.
.....but I also think it's a waste of money.
I have had connectivity issues with every Transmitter I have ever had from different manufacturers. The signal would just drop out & take forever to regain. They are no where nearly as reliable as an analog SPG. The biggest failure of them, I see is battery.
My wish is that they would come back with a 2" low profile gauge. I have a ScubaPro one that I absolutely love, easier to read! Anyone know why they quit manufacturing them? To get a 2" face, you have to have a full sized SPG or you can get a 1-1/2" face with the low profile, which is a bit harder to read.Quote:
Originally Posted by victorzamora
There is nothing wrong with using a transmitter cave diving so long as it is mounted to avoid hitting the ceiling. The data some computers give you while using a transmitter is valuable.
My suggestion is to hang it from a 6" HP hose and dangle it down in between back mounted doubles.
http://www.cavediveflorida.com/xmitt...0hp%20hose.jpg
That's not a bad idea Jim. His are mounted to his bailout and they kinda poke out, at least the way I see it.
I'm starting Cavern / Intro to Cave in two weeks. I have enjoyed using the Suunto EON Steel with transmitter because it (with latest firmware) gives you an estimate of gas consumption and gas time. I glance at this periodially to give myself feedback on how well I'm conserving gas. As I move into Cave I will be trained back mount first. My thought was to use two transmitters and two SPGs for redundancy. I have no experience with the Suunto switching between transmitters and that effort is probably a waste of time. I do not think the Eon Steel will monitor both at once. I do see the simplicity of just using SPGs without adding any more variables to this new experience. Advice appreciated.
Suggest speaking to your instructor first.Quote:
Originally Posted by Joe Schofield
Excessive redundancy is usually frowned upon, e.g. carrying two SPG's or two transmitters when using double tanks.Quote:
Originally Posted by Joe Schofield
Carrying one transmitter with a regular SPG as a backup should be plenty.
As Kelly suggested, you may want to ask your instructor. Chances are he would even recommend or require you to ditch the transmitter altogether.
There's no need for two spg's on a set of manifolded doubles and it's just adding to unwanted clutter. If you have an SPG failure, your dive is over, head home.
When estimating how much time you have left, your brain is better than any gadget out there. Electronic gadgets that estimate your gas consumption rarely take into consideration things like stress or changes in work rate.
Your instructor should teach you these things.
Best of luck!
I will go with my instructors advice. I figured he'd probably ask me to ditch the transmitter too. I also figured he'd not appreciate a call at 2am when I came across this thread and posted my question. ;)
Reasons I use a transmitter:
- I can monitor and quickly check the pressures in up to 6 tanks by looking at 1 screen (instead of finding 6 different SPGs)
- Computer provides 'gas time remaining' calculation based on breathing rate. Optional alarm if significant change is detected
- Fewer failure points than an analog SPG (1 o-ring vs multiple o-rings and a spindle)
- No chance to get an incorrect reading, such as with a stuck needle. Either you have a valid pressure reading or no signal.
- Audible and vibrating alarm when pressure reaches a set limit (extra safety if you are task loaded)
- If all of my lights went out, I could still see my tank pressures on the illuminated computer screen
I don't see the transmitter batteries as a problem, as they last for hundreds of dive hours and most wireless computers will give you plenty of warning in advance (just like the computer's own battery). I also like that when I download my dive log, it tracks my air consumption throughout the dive. I can see what my exact RMV was for each part of the dive and track this over time to see improvement.
Some people have told me that transmitters may malfunction in certain environments, but I have taken them in wrecks and caves with no issue (these are the Oceanic/Hollis transmitters). They are not for everyone, but in my opinion they offer some nice advantages!
biggest issue with two transmitters and two SPG's is your hose routing will look atrocious with things going every which way. Will also require your transmitters to point in towards the manifold and that will restrict your ability to do valve drills.
No issues with one on the right post, but you don't need 4 things to monitor pressure when most only use one....
[QUOTE=madmosche;290902]Reasons I use a transmitter:
- I can monitor and quickly check the pressures in up to 6 tanks by looking at 1 screen (instead of finding 6 different SPGs)
- Computer provides 'gas time remaining' calculation based on breathing rate. Optional alarm if significant change is detected
- Fewer failure points than an analog SPG (1 o-ring vs multiple o-rings and a spindle)
- No chance to get an incorrect reading, such as with a stuck needle. Either you have a valid pressure reading or no signal.
- Audible and vibrating alarm when pressure reaches a set limit (extra safety if you are task loaded)
- If all of my lights went out, I could still see my tank pressures on the illuminated computer screen
1-You using more than one gas at a time? You dont see a chance of confusion here?
2-This is auto calculated on a dive. As Ken said: in your head.
3-Maybe valid, if you dont consider an electronic gadget a failure point in itself.
4-Really? NO chance?
5-God No. No alarms.
6-Perhaps. And how would this help? Just get out, already. If 3 lights fail, its a bad day...expect a cave-in. Or snow.
Here is what to keep in mind from my worthless dribble: I dont care if you use them; I dont think they are necessary (hell I dont even have gauges on my bailout); when I dive OC, I MAY look at my pressure twice on the entire dive. Maybe.
That's me, though. My consumption doesnt consume me (sorry) and seldom dictates the dive.
REMEMBER: use them, I do not care...dont feel you need to defend this choice. Doc Deep used them and they worked fine...probably still are working.
Bob
[QUOTE=floridabob;290907]Might be too soon. Just sayin'.Quote:
Originally Posted by madmosche
Doing a valve drill with your isolator is a huge waste of time.Quote:
Originally Posted by tbone1004
The MTBF for spgs seem to be very minimal,otherwise you'd see a lot of posting from people about failures. But,when you've invested this much money in technology, ultimately you will use it. The big thing is have you practiced scenarios when something does fail? Do you have an automatic protocol for battery replacement, for example after x# hours dive time? I don't trust the device to give me dependable battery tracking. My Shearwater (as an example) will be in the red when it has a new battery sometimes, also I have had the computer go from yellow, then dead within a 30 min span.Quote:
Originally Posted by madmosche