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

[cruisekingkris]

Mid dive the battery died in my AI pod and I just went to my SPG for the rest of the dive. No need to turn the dive or tell DM that I had an issue. I changed batteries on the boat in between dives and was back to using the AI and having the SPG for backup. I use a very short 20" hose for the SPG and clip it to my BP so its always out of the way.

 

[CanadaDan]

I always run a thin 1.5" SPG on a thin miflex hose. I've had recurrent problems at our local dive area with my ai computer. I suspect it has something to do with the magnetic anomalies in the Canadian Shield (it eats cell signals, radio transmissions etc) I rarely get a proper pairing before the first dive, it tends to connect underwater away from the rocky area where I set up but I wouldn't enter the water assuming that.

 

[Marie13]

Diving backmount (single or doubles) I always had both SPG and transmitter. It’s different SM. The redundant SPGs can get in the way.

 

[tbone1004]

keep it in the dive bag in case it fails, but I don't keep them on, even in a cave

 

[Blackcrusader]

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?

I use the Cressi Digital SPG. So if my dive computer failed for any reason I have the SPG. It's no hassle to have both.

 

[MaxBottomtime]

If there was a way to read the battery life on my transmitter I might remove the spg, but I'll keep it for now. My spg is accurate, while my computer reads 200psi less.

 

[scubadada]

Hi @Corrupted_Diver

The main reason I have an SPG, in addition to an AI computer, is to quickly check all my tank pressures before leaving the dock. I find this faster and easer than using my computer. I have picked up several significant short fills that could be taken care of before the boat left. It's a pretty good way to screen for bad O-rings also. I use the SPG for my air on check just before diving.

In the last 10 1/2 years, I have had to use my SPG on 11/1448 dives 0.8%. Six of these 11 dives were entirely my fault, 2 AI computer battery dead, 2 transmitter battery dead, 2 forgot to transfer the transmitter when I switched regulator sets. Five dives were because a transmitter failed.

Over this period, I have dived a couple of different configurations. For 9 years, I dived an AI computer, a non-AI computer, and a SPG. For the last year and a half, I have dived 2 AI computers off a single transmitter, and a SPG. Due to my previous failures, I improved by battery habits and always have spares with me. I would probably not need my SPG on a dive unless my transmitter failed. I run the SPG under my left arm, attached to my left chest D-ring, easy to see, out of the way.

 

[tursiops]

I always run a thin 1.5" SPG on a thin miflex hose. I've had recurrent problems at our local dive area with my ai computer. I suspect it has something to do with the magnetic anomalies in the Canadian Shield (it eats cell signals, radio transmissions etc) I rarely get a proper pairing before the first dive, it tends to connect underwater away from the rocky area where I set up but I wouldn't enter the water assuming that.

What brand transmitter/computer?

 

[GreggS]

If there was a way to read the battery life on my transmitter I might remove the spg, but I'll keep it for now. My spg is accurate, while my computer reads 200psi less.

This was my problem on the Fiji trip. I had no way of reading the battery level of the transmitter until it died. I was using a Suunto Vyper Novo. Now I am using an Oceanic OCi which does read the battery level in the transmitter so I can check it before a trip (I still do carry a spare battery, though.) Plus the battery in the Pelagic transmitter is a lot easier to change than the Suunto and you don't have to worry about cracking the cover or stripping the plastic threads like you do on the Suunto.

 

[jonhall]

do you really need the hose SPG?

The answer for me is no. Although I have an air integrated console (Suunto Cobra), a transmitter attached to my Mikron reg would take the same, and only, HP port - so I can't attach a SPG. Have been without a backup for quite some time. For those wondering, the AquaLung Mikron today comes with 2 HP ports and 4 LP ports - I got mine in 2010 - it only has 1HP and 4 LP ports.