Transmitters on Short Hoses?

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

Two of the very best cave divers/instructors/explorers that I have ever met use transmitters instead of SPGs. So apparently its not mandatory to use SPGs, unless you meant to say 'SPGs or transmitters'. I.E. some kind of instrument that tells you how much gas you have.

I'm sure at some point in the aviation world there were all kinds of discussions about replacing mechanical instruments with electronic ones, and resistance to that transition. Maybe there still is, I really don't know.
Just be wary that that some technical/recreational divers are given gifts as a means of promoting a new fad. A good diver should be comfortable with any equipment arrangement or adapt very quickly.
 
Transmitters have been around for a quarter century now. They aren't a new fad. They're steadily replacing mechanical SPGs the same way dive computers have largely replaced plastic dive tables. Transmitters are more dependable, more accurate, more durable, and more streamlined for sidemount than brass & glass SPGs. Although SPGs still have a couple advantages.

While first generation transmitters often had connection issues, that's no longer the case. With the exception of a negligent diver failing to monitory battery life, it's rare for a modern transmitter to lose connection for more than a few seconds. Even if that rare case occurs and the transmitter should fail, the display turns to garbage and provides an obvious and immediate indication to turn the dive within the Rule of Thirds. In contrast, when mechanical gauges fail they tend to stick indicating more gas than is actually available, presenting a potentially dangerous situation by overestimating remaining gas.

The transducer in a transmitter is accurate to within 2 bar/30 psi compared to the standard bourdon tube SPGs which are only accurate to within 15 bar/220 psi. That lack of SPG accuracy is a secondary reason recreational divers were taught to end a dive at 50 bar or 500 psi. The thick plastic shell and static internal parts of a transmitter are much more difficult to damage from impact stress than the glass face and moving mechanical parts of a SPG. For sidemount, the transmitter is tucked out of the way along the lower valve and tank neck and protected within the diameter of the tank rather than alongside it or above it. It is further protected by its position against the diver's body. For many divers, a transmitter is also easier to read on a backlit digital wrist-mounted computer than a SPG's analog glow-in-the-dark face on a short hose.

The benefits of an SPG over a transmitter are no need for a battery (although the hose & spool must be maintained) and a significantly lower price point. A high quality SPG costs just 20% of the price of a transmitter (US$70 vs. US$350 not factoring in customs duties or taxes). SPGs can also be more comforting for people less at ease with technological change. It's this final point which causes some divers to use a SPG as "redundancy" to a transmitter where they would never place two SPGs on a sidemount tank.
 
Transmitters have been around for a quarter century now. They aren't a new fad. They're steadily replacing mechanical SPGs the same way dive computers have largely replaced plastic dive tables. Transmitters are more dependable, more accurate, more durable, and more streamlined for sidemount than brass & glass SPGs. Although SPGs still have a couple advantages.

While first generation transmitters often had connection issues, that's no longer the case. With the exception of a negligent diver failing to monitory battery life, it's rare for a modern transmitter to lose connection for more than a few seconds. Even if that rare case occurs and the transmitter should fail, the display turns to garbage and provides an obvious and immediate indication to turn the dive within the Rule of Thirds. In contrast, when mechanical gauges fail they tend to stick indicating more gas than is actually available, presenting a potentially dangerous situation by overestimating remaining gas.

The transducer in a transmitter is accurate to within 2 bar/30 psi compared to the standard bourdon tube SPGs which are only accurate to within 15 bar/220 psi. That lack of SPG accuracy is a secondary reason recreational divers were taught to end a dive at 50 bar or 500 psi. The thick plastic shell and static internal parts of a transmitter are much more difficult to damage from impact stress than the glass face and moving mechanical parts of a SPG. For sidemount, the transmitter is tucked out of the way along the lower valve and tank neck and protected within the diameter of the tank rather than alongside it or above it. It is further protected by its position against the diver's body. For many divers, a transmitter is also easier to read on a backlit digital wrist-mounted computer than a SPG's analog glow-in-the-dark face on a short hose.

The benefits of an SPG over a transmitter are no need for a battery (although the hose & spool must be maintained) and a significantly lower price point. A high quality SPG costs just 20% of the price of a transmitter (US$70 vs. US$350 not factoring in customs duties or taxes). SPGs can also be more comforting for people less at ease with technological change. It's this final point which causes some divers to use a SPG as "redundancy" to a transmitter where they would never place two SPGs on a sidemount tank.
I'm not here to dissuade anyone from purchasing several transmitters for all their diving needs. You put in a different brand in a Shearwater and the battery life symbol fails to monitor how much time before you need a new battery. I use the ones that don't leak. SPGs running down the tank on sidemount is as streamlined as you get. 50 bar rule is for novice divers. 4 transmitters for 5 sets of regulators adds up in cost. As I mentioned on my last post, when an incident occurs everything will blur on screen. An SPG mounted on a shoulder D-ring (doubles) takes one glance to know exactly where you stand. I believe this is one reason why novice divers don't monitor consoles well. It's called information overload.
 
Just be wary that that some technical/recreational divers are given gifts as a means of promoting a new fad. A good diver should be comfortable with any equipment arrangement or adapt very quickly.

What are you talking about, if you don't mind me asking? Are you suggesting that the expert divers I was referring to are acting as influencers for a computer company that has an AI option?
 
Transmitters have been around for a quarter century now. They aren't a new fad. They're steadily replacing mechanical SPGs the same way dive computers have largely replaced plastic dive tables. Transmitters are more dependable, more accurate, more durable, and more streamlined for sidemount than brass & glass SPGs. Although SPGs still have a couple advantages.

While first generation transmitters often had connection issues, that's no longer the case. With the exception of a negligent diver failing to monitory battery life, it's rare for a modern transmitter to lose connection for more than a few seconds. Even if that rare case occurs and the transmitter should fail, the display turns to garbage and provides an obvious and immediate indication to turn the dive within the Rule of Thirds. In contrast, when mechanical gauges fail they tend to stick indicating more gas than is actually available, presenting a potentially dangerous situation by overestimating remaining gas.

The transducer in a transmitter is accurate to within 2 bar/30 psi compared to the standard bourdon tube SPGs which are only accurate to within 15 bar/220 psi. That lack of SPG accuracy is a secondary reason recreational divers were taught to end a dive at 50 bar or 500 psi. The thick plastic shell and static internal parts of a transmitter are much more difficult to damage from impact stress than the glass face and moving mechanical parts of a SPG. For sidemount, the transmitter is tucked out of the way along the lower valve and tank neck and protected within the diameter of the tank rather than alongside it or above it. It is further protected by its position against the diver's body. For many divers, a transmitter is also easier to read on a backlit digital wrist-mounted computer than a SPG's analog glow-in-the-dark face on a short hose.

The benefits of an SPG over a transmitter are no need for a battery (although the hose & spool must be maintained) and a significantly lower price point. A high quality SPG costs just 20% of the price of a transmitter (US$70 vs. US$350 not factoring in customs duties or taxes). SPGs can also be more comforting for people less at ease with technological change. It's this final point which causes some divers to use a SPG as "redundancy" to a transmitter where they would never place two SPGs on a sidemount tank.

A guy dropped turned on his tank and dropped the spg from waist-height onto the boat floor.
It shattered. And this was before the first dive of a two-tank dive (boat wouldn't be returning to shop after first dive).
Luckily we managed to install the boat captain's emergency bcd spg on his first stage.
 
What are you talking about, if you don't mind me asking? Are you suggesting that the expert divers I was referring to are acting as influencers for a computer company that has an AI option?
Yes, I do recall quoting your post, but maybe you can clarify the expert divers you were referring too? My point was that instructors are given dive equipment to try out, and that influences novice divers into thinking it will be good for them without weighing up the pros and cons. An indirect way of marketing equipment. Any more queries you need to clarify?
 
https://www.shearwater.com/products/peregrine/

Back
Top Bottom