PLBs Can Save Your Life

[CuzzA]

My Custom Divers canister arrived. Nice! Easy to operate. Slick design webbing case to hold it on my belt. Very well made. I like it much better than the HDV one.

What PLB do you have? On my ResQLink + I had to shave about a 1/16" of an inch off a section of the antenna cover to get it to fit. I'm wondering if they make the canisters slightly bigger now.

 

[tursiops]

What PLB do you have? On my ResQLink + I had to shave about a 1/16" of an inch off a section of the antenna cover to get it to fit. I'm wondering if they make the canisters slightly bigger now.

FastFind 220

 

[JohnnyC]

Holding your hand above your head for 45 minutes is harder than you'd think, even with minimal weight. I'd clip it to a d-ring with the antenna vertical and float on my back.

PLB manuals are very clear that they want a vertical antenna. I'm not sure how it would affect the unit with it being in some other orientation, but every manual I've read specifically states that the antenna should be vertical. I don't know a lot about antennas but I'd trust them if they said it's important.

PAB's where the antenna flips up from the case seem to have a little bit better form factor. You could easily hang one from a d-ring on top of an SMB and have a pretty good chance of the antenna being close to vertical.

 

[tursiops]

Holding your hand above your head for 45 minutes is harder than you'd think, even with minimal weight. I'd clip it to a d-ring with the antenna vertical and float on my back.

PLB manuals are very clear that they want a vertical antenna. I'm not sure how it would affect the unit with it being in some other orientation, but every manual I've read specifically states that the antenna should be vertical. I don't know a lot about antennas but I'd trust them if they said it's important.

PAB's where the antenna flips up from the case seem to have a little bit better form factor. You could easily hang one from a d-ring on top of an SMB and have a pretty good chance of the antenna being close to vertical.

Those antennas try to have a cardioid pattern, meaning conical lobes at about 45 deg. The vertical antenna maximizes the chance of hitting a satellite. A horizontal antenna points the cone toward the horizon, in some direction, which may not be the direction where a satellite is.

 

[Akimbo]

Holding your hand above your head for 45 minutes is harder than you'd think, even with minimal weight.

Agreed, to say nothing of 45 minutes being exceptionally optimistic. Miami probably has among the fastest responses in the world. Compare that to somewhere off sparsely populated islands in the south Pacific or Caribbean with no SAR capacity. Now add being swept away from the leeward side of the island(s) with 3'+ swells and wind blowing white water over your head.

You could also be lost off a world-class SAR base, except it is in a place like the North Sea or US north Atlantic. You find yourself in 6'+ seas, the sun is setting, your drysuit is leaking, and need both hands free to manage the situation.

Hope for the best, but plan for the worst.

 

[KevinNM]

on the canister why does it need to be delrin is that is so costly?

Delrin is what pretty much everyone makes battery canisters out of. They typically they are rated to 100 meters. There isn't that much demand for high-end gear, so it's made by the vendors at low volume. 10-20 parts a week is really different from 1000 parts a week, at that point you get economies of scale and can justify much more expensive equipment that is much faster and takes lots less manual work per unit.

 

[Akimbo]

on the canister why does it need to be delrin is that is so costly?

Delrin is what pretty much everyone makes battery canisters out of.

Delrin is a relatively expensive plastic, but machines very fast and is widely available in different diameters and thicknesses. It is a favorite in many industries to make assembly fixtures and other types of low production parts. Unfortunately most of the material for a housing is waste because they are machined from solid round-stock, which also adds to the machining time.

An alternative is to make a housing out of Polycarbonate tubing, but that requires machining plugs for both ends since it can't be effectively bonded or welded at the closed end. Here is an example of an out-of-production product from OMS:

IMO, a threaded cap is less desirable than retainers than can be easily operated with small, gloved, cold, and wet hands.

 

[KevinNM]

Battery will discharge with time. You need to test your PLB at least once a year. That'll shorten the battery capacity further. You don't want to have still enough charge to transmit the emergency alert when you need it. It would be bad deal when you are lost at sea, pressing the red button and finding out that it only last for say 2 hours.

When the El Faro freighter went down in a hurricane a few years ago the non-GPS EIPRB didn't last long enough to get a fix. They detected it, but when the next sat passed over it was gone.

 

[KevinNM]

It might be the type of pipe or end cap that you used, there are different pressure ratings for the pipe and fittings. I will try to make one with the higher pressure fittings and take it to depth to see if it leaks.

You really don't want to be around it if it implodes. PVC also breaks down over time, which is why it's incredibly unsafe to use it for air lines in a shop.

 

[KevinNM]

This thread has opened my eyes to many things that I did not pay super attention before. I will get the PLBD but am also thinking of getting one that has a strobe on it or get a small waterproof strobe.

Need to figure out the container portion to keep the stuff in. @Akimbo hinted at something earlier and in other posts which I will look into. So did @CuzzA above. Also need to find radar reflecting tape for my current SMB.Ultimately though the light monkey one being proposed maybe the way to go.

You can get a strobe that is rated for deeper than you will ever need and just stick it in a
pocket. AQ-4 MkII Strobe Light I Jotron I Your Communication Partner

But the ACR ResQLink has a strobe too, not sure how it impact the battery life or how good the strobe is.