Full face masks?

[dry heat diver]

I use an AGA FFM and am extremely pleased with it. Compared to the normal mask and regulator set up I find it to be much more comfortable and nearly impossible to flood. When I deliberately flood it with water in training it is virtually self clearing. I also have no problem clearing my ears with the built in blocks used to close off the nostrils and I find less need for clearing than with a mask and reg. It does draw slightly harder than a reg but that feature can be adjusted. A full face mask does consume more air than a reg. The disadvantages are a slight restriction of vision when looking down and in an OOA situation it must be removed in order to use a buddy's octopus. I carry a regular mask in a bag on my BCD and practice switching back and forth, which really isn't all that difficult. I am a newbie diver and may change my opinion as I gain more experience, but right now it works very well for me.

 

[james croft]

I use an AGA FFM and am extremely pleased with it. A full face mask does consume more air than a reg. The disadvantages are a slight restriction of vision when looking down and in an OOA situation it must be removed in order to use a buddy's octopus.

You can get a gas switching block manifold that allows you to switch to a pony bottle, etc. without having to remove the ffm. There are several on the market. I use the Kirby Morgan and it is bulletproof. In an ooa situation you turn a knob and your now breathing off a pony. It can also be used when diving with surface supplied air and in the event of a failure you can switch to your bailout bottle. It has a check valve on it and is made of brass, unlike some of the other blocks out there that are made of delrin and are prone to leaks due to sand scratching surfaces, etc.

 

[Thalassamania]

But this brings me to my second point, has anyone ever used the comm port on a FFM to install a portable radio system. I think that would pass the time

Radio waves don’t penetrate water. If you mean sending entertainment down a wired system, sure … it’s done all the time.

Does anyone have any experience with the JMC Super Mask?

Pro's / Cons / Comments?

I’ve not used that one specifically, but I’ve used perhaps a half dozen similar items, none of which served well. But if anyone could make the concept work (and it’s a sound concept) it’s Bev Morgan and his crew, I’d be more that willing to try it again just based on the fact that it’s in the Oceanic line.

You can get a gas switching block manifold that allows you to switch to a pony bottle, etc. without having to remove the ffm. There are several on the market. I use the Kirby Morgan and it is bulletproof. In an ooa situation you turn a knob and your now breathing off a pony. It can also be used when diving with surface supplied air and in the event of a failure you can switch to your bailout bottle. It has a check valve on it and is made of brass, unlike some of the other blocks out there that are made of delrin and are prone to leaks due to sand scratching surfaces, etc.

Oceanic makes one too.

Oceanic Block



also:

RSV-1 Redundant Supply Valve



There are a lot of different FFMs out there, the range form the USD and IST masks that just had a little cup that kept your chin dry and had a regulator moughpiece inside to very sophisiticated masks to go for thousands of dollars.



Here are a few that are available:

IST

AGA

ScubaPro

Ocean Reef

Poseidon

EXO-26

TEC I

Aquadyne

Kirby Morgan

 

[MikeFerrara]

Radio waves don’t penetrate water.

Yes they do. Radio is currently being used to map UW caves to the surface. A diver takes a directional transmitter UW and transmits from survey stations. The signal is recieved on the surface by a directional antena and the location marked. It can also be used for voice communication althoutgh the mapping equipment isn't designed for that.

Radio mapping has been done at Peacock. Jason Gully radio mapped Vortex and I was present when Jasons crew mapped a cave in Kentucky using equipment designed, built and oporated by Brian Pease. Brian was there and being an electronics guy myself, I got to hear plenty about how it works. I think Jason eventually got his own equipment and used that at Vortex. In fact, I was supposed to build and test it but I got busy with other things while Jason was rounding up parts and I think he eventually got someone else to do it.

As of the time I had the chance to talk with Brian, I think the UW and UW to surface com units that Wes Skiles was using was also radio. If I remember right Brian built that stuff as well. Also, If I remember right (a lot of memory involved here), they used regular ultrasonic FFM comms and stripped out the ultrasonics and replace it with a radio...don't quote me on the details though.

Aside from parks like Peacock or Vortex where the cave is mapped to the surface for the ammusement of guests, another primary use is where mining or quarry oporations may be close to a flooded cave. If the cave can be accurately mapped to the surface, mining oporations can more easily avoid breaking into the cave and getting flooded.

Another interesting point is that the equipment can be roughly calibrated to measure distance. Not only can you map the survey station to the surface but you can get a prety good idea of how far below the surface the survay station is.

I'm probably a little out of touch with what's been going on lately so they may very well have made some improvements in this stuff that I'm not aware of.

 

[MikeFerrara]

For any one who is interested here's Brians website where you can read all about how it works and is used, including schematics. http://radiolocation.tripod.com/

From the site

Be Sure to Check out this Website!
Visit http://www.floridasprings.org/expedition/dispatch2 to see examples of real-time diver tracking at 300 ft depth with 3496 Hz gear and also 2-way voice comms with a diver through rock using modified 32 KHz gear designed for acoustic comms. Photos, video and audio clips are included. Dispatch3 shows diver tracking at more reasonable depths. For practical reasons, the restaurant and bowling alley tracking were simulated, but the cave really does go right under the alleys! The Website is supported by the State of Florida for educational purposes.

If I had remembered that I had Brians business card I would have skipped the last long winded post and just linked to the website in the first place. LOL

 

[Thalassamania]

Sorry Mike, I was inexact. I dont't believe you can receive commercial radio stations underwater (which is what the OP was asking about, not mapping water traps).

 

[scarefaceDM]

If you never tried a Fullface..give one a try.

I use to dive with the Nira II, Ocean Reef. I loved it and hated it. It took me about 10 dives to get use to it. Once I mastered the Mask..I loved diving with it. The only thing I realy did not like was the fact that it was a hard breather. and if you happen to look down too much you had to switch the vent valve to UP to avoid it from freeflowing. Aside from that, It was great.

I tried the new Ocean Reef Space, that too is a nice mask. I also dove with the AGA...EXO 26. Great FFMasks.

I sold my FFM after 80 dives on it...i did not see a need for it as the Novelty wore off and I was going into more streamlined configuration. I was the cool guy on the boat when I whipped out the mask...but the coolness wore off. On the flip side. It was nice in extreme conditions, water where I would not want to swim in...but recuperating things made the work more comfortable.

Do not knock it if you have not tried it.

Safe dives
Stephen

 

[MikeFerrara]

Sorry Mike, I was inexact. I dont't believe you can receive commercial radio stations underwater (which is what the OP was asking about, not mapping water traps).

Nope, I don't think you'll get your local country station.

 

[james croft]

Thallassamania,
That Oceanic block looks suspiciously like a Kirby Morgan Block unless my old eyes are deceiving me. Maybe it is produced by KM ?

 

[Thalassamania]

I think it is.