Does everyone really need an SPG? (w/transmitter)

[hedonist222]

If you've installed an air pressure transmitter that shows you remaining pressure on your dive computer, do you really need the hose SPG?

Sure, if the transmitter or computer malfunctioned, you needn't end the dive because the spg is there.

But to retain the spg in the unlikely event of a malfunctioning transmitter and be able to continue that dive?

You'd bring and store your spg and of the transmitter malfunctions, it takes a movie with a wrench between dives to connect.

Or are there other reasons to have the spg?

 

[BoltSnap]

If your computer malfunctions and you don't have a backup computer on you during the dive, you are going to end the dive anyways because you can't continue the dive without your knowing your depth, NDL and the other essential information provided by the computer, your spg in itself isn't critical and won't be a reason to continue your dive in this scenario. Your dive is over and you're going up.

I have two computers with two different transmitters on my regulator, no spg.

 

[Edward3c]

This goes back to then computers first hit the mainstream. Did we still need to have a watch and depth gauge? No, but for a number of years people did.

I got an integrated computer 2 years ago, and yes I still have the spg attached. Do I use it during dives? Rarely. Has it saved a dive? Yes. When I’ve forgotten to attach the transmitter.

However, when the current spg fails I’ll most likely not replace it.

 

[GreggS]

Is an SPG necessary? Not really. Lots of divers don't use one with a hoseless AI computer. But I do. Last year on a trip to Fiji, the battery in my transmitter died midway thru our 2nd dive. But I was able to continue the dive since I had an SPG and all other info was still available on the DC. Since I did carry a new battery with me, I changed it before the next day's dives and all was good.

On that dive it was nice having it. Otherwise I rarely look at. I"ve thought about taking it off my rig but haven't yet.

 

[hedonist222]

If your computer malfunctions and you don't have a backup computer on you during the dive, you are going to end the dive anyways because you can't continue the dive without your knowing your depth, NDL and the other essential information provided by the computer, your spg in itself isn't critical and won't be a reason to continue your dive in this scenario. Your dive is over and you're going up.

I have two computers with two different transmitters on my regulator, no spg.

Good point but the topic is about a redundant spg when you have a transmitter installed.

 

[hedonist222]

I took mine off about eighty dives ago last year.
I still have it in my dive bag back at the dive center.

 

[J-Vo]

The only time I have had a transmitter fail is when I put the wrong O-rings on the battery compartment. Both failed at the same time on the checkout dive at the beginning of a trip in Cozumel. I cleaned the salt water and battery acid out of those SPGs with alcohol and a cotton swab and they have been functioning fine for several years since. Carry SPGs and batteries for backup in your save-a-dive kit and your good. Check the battery level before each dive day or just put fresh batteries in before the trip.

 

[Marie13]

I did my recent cavern/intro to cave class with just two transmitters, NO spg. I’d been open water diving SM with SPGs, but I realized checking in a dark cave would be a two handed operation, and having it on my wrist is just so much easier. Especially when you have to switch regs every X PSI (whatever your switch number is). I have a Perdix on each arm and both transmitters are fed to both computers.

I had no issues at all. SPGs were in my bag.

 

[BoltSnap]

I did my recent cavern/intro to cave class

Where did you do this course? FL?

 

[Marie13]

Where did you do this course? FL?

No. Wisconsin. Former lead/zinc mine.