Vytec transmitter

[WreckWriter]

Scubaroo once bubbled...
Aren't both the SPG and the HP port on regs 7/16"? Didn't realise they were different - at work at the moment so can't check.

Not talking about that, I'm talking about the fact the the HP hose, the end that goes into the port, has a tiny hole (too keep HP volume down). Possibly the transmitter also has this, in which case it wouldn't matter.

Tom

 

[Scubaroo]

I think it's become all hypothetical anyway. I put the transmitter on the reg last night, and on the DST first stage at least, it's not sticking out at an angle where it's going to be the first thing to hit the deck if the worst happened. It's almost at a right angle to the DIN connection, and there are a couple of hoses running about it, so it looks fairly well protected. Anyway I've just screwed it into the first stage and will leave it there. Diving it this weekend so will know for sure then

 

[TexasMike]

One thing to practice with is getting the transmitter and computer to synch up....

At first...there were be several times that I would set up everything and then walk out of transmission range...Then the unit would lose its "lock" and not synch back up when I was ready to get back into the water.

The best thing to do is to not turn on the computer or air until you are ready to get into your BC and dive.

But if something does go strange, shut down your valve and purge the regs (causes the transmitter to reset). Then with the computer on, hit the lower right button several times until you see CODE: - -. Then turn on the air. Your transmitter and computer should re-synch.

Practice this a bit so that you don't hop in the water just to find that your computer is not showing you your air data.

 

[DiveRite-SW]

I believe the DST has a large hole opening in the body (not thread size, but the actual air-hole) and therefore assumes the neck-down is in the hose-end fitting.

It may make a difference too, to see which side of the 1st stage the transmitter works better on. I have one computer that works better the farther away from the transmitter (within reason, duh!) it is, even though the book (I read the directions on that computer, how about that, TexasMike?) said to put it on the same side as the wrist-unit is worn, so it ended up on opposite side of the reg-body.

For those considering (or who have already) converted over to the Vytec or other hoseless computers and eliminated the big long SPG-hose altogether, consider getting a little finger-gauge to screw into the other HP port. Thataway, you can easily check yer tank-pressure without firing-up the Vytec or making it lock and then possibly unlock later (as TexasMike pointed out). They have a itty-bitty gauge-face and are only about 1" long overall. Have seen several different brands, but probably all the same mfgr.

Ok, yeah, it introduces a few more failure-points. But it is very convenient, if yer willing to sacrifice a little bit. DIR'ers can unread this entire post ;-})

 

[Scubaroo]

It's the one piece of my gear that's decidely not DIR. But I want the air integration feature (it's called Progress ). I kept the 24" SPG as a backup.

 

[TexasMike]

Currently, I've got the transmitter pointed "to the right" when I'm in my BC, and the Vytec on my left forearm.

So far, with the batteries being as new as they are, there have been no problems getting the signal between the first stage and my arm.

I've also noticed that I could walk to the other side of the dive boat and still receive a signal (the little lightning sign flashes).

And so far I'm very happy with my purchase (yes ronbo...you get some credit for this ut: )

 

[divernva]

Might be a good idea to continue using your SPG as the primary. Will help to keep core skills sharp.

AI will provide good stats for your logbook. Have fun.
Ken

 

[TexasMike]

Here's a good question for debate....

When the cylinder presure is getting down on the low side (say 1200 psi and less), which device is giving you the more accurate reading?

Remember, the mechanical SPG is designed to give you the most accurate reading in it's middle range (that's why many SPG's go up to 5000 psi).

Since obtaining my Vytec, I've noticed that when the dive is ending, and I'm on my way up the line, the difference between what the Vytec displays and what is shown on my Dive-Rite SPG is sometimes as much as 200 PSI. Of course I'm following the more conservative reading (the Vytec), but Divernva's question just above made me more curious about this situation.

What do the rest of you folks think? Is the pressure sensor in the transmitter more accurate than the SPG? Or the other way around?

 

[Scubaroo]

Got any other SPGs you can hook up to the regulator to test it? Mine won't be getting wet until at least after this weekend, I'll let you know how mine compare. 200psi is a lot - that's almost 10% accuracy error in a LP tank.

 

[DiveRite-SW]

The question becomes more of whether a specific electronic or analog sensor is more accurate.

In general, an electronic sensor is usually a piezo-material (Piezo-materials are semi-crystalline structures that have very precise, accurate and repeatable electronic characteristics when subjected to pressure). Analog sensors are mechanical devices (that have springs, gears, and pointers) and are subject to bigger errors and deviations.

Given any typical dive-computer, it will have the electronic sensor to interface with tank pressure, water pressure, etc, while the analog SPGs are making-do with their mechanics. Therefore, the electronic one is going to be more accurate throughout its range of use.

So, unless TexasMike wants me to open up his beloved Vytec (please, Mike, I wanna see what's in it) and do some exacting measurements, I'd guess the mechanical ones are generally more inaccurate.