PLB for NE

[arkstorm]

So you’re saying the plb is better because it’s in someone’s pants pocket versus on their console? I’m not really sure I get your point. Both devices transmit your gps location via a satellite network afaik..

…Yes that is exactly what I’m saying…because if I find myself overboard, the rescue beacon in my pocket will be a lot more helpful then the one still sitting in the cup holder on the boat that is now speeding away from my position.

 

[Nick_Radov]

For those who don't know, an InReach is a satellite based two-way texting device that also has an SOS feature. You can communicate with the wives on shore, communicate with other boats when you don't want to broadcast information on an open VHF channel, get the weather, other features. It is subscription based (though I'm not sure if the SOS feature requires an active subscription). It uses rechargeable batteries that, depending on the device, last from as little as a few hours to as much as several days.

Garmin inReach devices communicate through the Iridium satellite constellation. The SOS feature requires an active subscription.

If the device is powered off then the rechargeable battery will last months. But then to use it you have to remove it from the dive case and turn it on. There's some risk of losing it if you do this while floating at the surface. Personally I leave mine powered on and clipped in my pocket while out on a boat. That way I could trigger an SOS via Bluetooth at the surface using my paired Garmin Descent dive computer. But leaving it powered on discharges the battery at up to 10% per hour while you're underwater because it continuously hunts for satellites, so for multi-day dive trips you'll need to recharge.

One benefit of the inReach is that it's really compact and can be used for other activities as well. I bring mine along whenever I go hiking/cycling/driving out of cell phone range.

 

[geordy]

In comparing a PLB vs InReach, I have sold them, flown in SAR aircraft, and am currently looking myself. With a PLB, my understanding is that it sends a 406mhz signal with the coordinates of your location when you pushed the button. It does not update that location. So if you are drifting, they may not be looking in the correct location. Some of the units may also put out a 121.5 VHF signal which can be homed in on, but I’m not sure how long it depletes the battery. I would assume no more than a couple hours at most.
The nice thing is that it works with multiple countries satellite systems. Outside of the US, I’m not sure how long it would take for responders to get into your area to search for you.

The inReach, though a subscription, I think is a little better. The key part is the gps sending updates on your location. It also allows you to send messages and receive them. Yes it goes to a commercial operations center, but they have years of experience now to work the bugs out of their system. It would still take time to get a response spun up, but they can be tracking you a bit easier.

I personally would prefer a PLB for over land and the InReach for water.

I welcome any responses that have different ideas about this.

 

[chaad]

With a PLB, my understanding is that it sends a 406mhz signal with the coordinates of your location when you pushed the button. It does not update that location.

I hadn't thought of this possibility. I assumed it would continue transmitting the location every few minutes. I've done a little googling but couldn't find information either way. Can anyone else confirm this is how PLBs function?

 

[Larryjd1]

I use the InReach when I am cave diving in Mexico to communicate with my wife back in the US.

I send a pre-programmed "Going in" message before I enter the cave, and then send an "I'm out" message when I exit. She receives them as text messages on her phone. I don't expect the Mexican authorities to respond in any kind of timely manner, so she has the contact info of local divers who I know well enough that they'd be willing to do a wellness check if need be.

I take it with me in it's waterproof case just in case I should have to do an emergency exit in a different cenote for both it's texting and map capabilities.

While it says that it needs clear access to the sky, I've found that within a couple minutes it ends up connecting with a satellite even while among trees, though obviously I do look for the most open area available.

 

[chaad]

With a PLB, my understanding is that it sends a 406mhz signal with the coordinates of your location when you pushed the button. It does not update that location. So if you are drifting, they may not be looking in the correct location.

I hadn't thought of this possibility. I assumed it would continue transmitting the location every few minutes. I've done a little googling but couldn't find information either way. Can anyone else confirm this is how PLBs function?

I did a little research and found that fortunately @geordy isn't exactly correct. Here's an excerpt from ACR ResqLink 400 manual:

For the first 6 hours after beacon activation, the internal GPS will start up every 30 minutes, search to find your LAT/LON, and incorporate it into your next 406 MHz signal. If for any reason the internal GPS cannot update your LAT/LON, your last position will be used for the next four hours - at that time, the green LED will stop blinking and the red LED will flash once every 5 seconds until new GPS data is obtained. Between 6 hours and the end of operating life (minimum of 24 hours), a GPS location update is attempted every 60 minutes.

The ACR devices will transmit your coordinates every 30 minutes for the first 6 hours and every 60 minutes thereafter until the battery dies.

 

[geordy]

I did a little research and found that fortunately @geordy isn't exactly correct. Here's an excerpt from ACR ResqLink 400 manual:



The ACR devices will transmit your coordinates every 30 minutes for the first 6 hours and every 60 minutes thereafter until the battery dies.

You are correct. I ended up talking to someone from NOAA and the USCG a couple weeks ago and found out I was wrong.

 

[Dan]

I carry both PLB1 & nexGen MRG

 

[chaad]

I carry both PLB1 & nexGen MRG

View attachment 873245

I have seen your custom housing posted around on various threads, it is a beauty! I'd love to have one of my own. Would you be willing to share the specs and schematics you provided to your fabrication shop?

 

[Dan]

I have seen your custom housing posted around on various threads, it is a beauty! I'd love to have one of my own. Would you be willing to share the specs and schematics you provided to your fabrication shop?

Sure, I posted it somewhere in Scubaboard, but I can dig through my record and post it here again.