Author Topic: Emergency signal beacons (EPIRB) (Read 731 times)

lilabner · « **on:** February 13, 2005, 05:16:00 AM »

Can these beacons be set like an alarm clock to go off at a certain time? I hunt the local area alone and carry a cell phone and GPS so could call for help if injured. However, if I was injured and knocked out, the phone/gps wouldn't do any good.

Siskiyou · « **Reply #1 on:** February 13, 2005, 10:33:02 AM »

lilabner: Interesting subject. One that most outdoorsmen should have at least a passing interest in. I think of most EPIRB type units as being fixed mounted in boats or aircraft location devices. PLB (Personal Locator beacons) are about the size of a gps unit. Some come with a built-in gps and others can be connected to your personal gps receiver.

I have question regarding activation. Some are activated when they come in contact with water or manually activated. Does this mean that you must fall out of your stand into a pond to get help? The units will broadcast to a satellite which sends a signal to Virginia. A few years back I was working with helicopters in the field. A late working mechanic trip the location device accidently just after midnight. We soon had security people and the State Police all over the place looking for a down ship.

I phoned a friend who is a LEO in snow country. Avalanche risk, snowmobiles, and skiing is a way of life five months a year for him. The other seven months a year it happens on bare ground. He just completed a S&R training session using new Avalanche Beacons. The avalanche beacons have a short range signal. His thoughts are that a PBL unit would be great 12 months a year.

A question comes to mind if these devices are effective in heavy tree cover? If they are depending on a gps to provide a location the unit might be useless in heavy cover or if a body is on top of the unit, blocking the signal.

Rustyinfla · « **Reply #2 on:** February 13, 2005, 01:30:25 PM »

Here in Fla where boating is a way of life the price of the EPIRBS are coming down but they are still a way over $500. there is a company here that will rent them though. I'm not sure about the rates.
As I understand it, an EPIRB works on a frequency that will tranmit direct to a satalitte. The avalanche beacons work on a UHF or VHF frequency. I have seen the locator antennas and they look just about like the ones we use as ham radio operators to locate beacons as a test in the 2 meter band.

Rusty <><

Siskiyou · « **Reply #3 on:** February 13, 2005, 05:55:32 PM »

Rustyinfla: You are correct. The avalanche beacon has a transmitting range of about 80 meters. Those that are not buried in the avalanche turn their beacon into a receiver to locate those who are buried. I sure wish we had them years ago when probing for victims. I checked with my friend to find out what they are currently using. At this time it does not appear that PLB, ELT, and EPIRB beacons are commonly found in rural S&R's except for down aircraft. I suspect that EPIRB'S are more common off shore and in coastal waters. Maybe the Great Lakes??

I believe the PLB units transmit at 406 MHz and 121.5 MHz. Hopefully the signal is picked up by Satellite and relayed to Langley, Va.(?) The information is then relayed to the appropriate S&R. I understand that ELT and EPIRB transmit at 121.5 MHz and this is the common receiver frequency for S&R. Apparently there is a phase-in period for the PLB 406 MHz units so that S&R units can update their equipment. I am assuming that a handheld scanner could be programed to receive 406 MHz.

In my area a lot of S&R units are volunteers working under the direction of the County Sheriff. Another cost burden for the volunteers? If this is adopted by outdoors folks it will save lifes and money very fast. I believe the cost factor will keep most folks from buying and maintaining them. Cost is around $550 per unit.

In regards to one of lilabner's question, I do not believe there is anyway of pre-setting one of these units to go off at a certain time. I believe that they have to be set off manually or contact with water. My wife is my Personal Locator Beacon. When I take off hunting or on a hunting- camping trip I print up maps of the area I plan on hunting. I also provide Lat/Longs of my primary and secondary camping locations. I have also created (gps) routes of the road systems in the mountains we hunt. These(gps) routes are printed out on USGS California Series software topo maps. When possible I try and contact her via cellphone every two days. One of my favorite camps is up a nasty 4x4 road at 7600 foot elevation. Because of it's location I have cellphone service in my sleeping bag. But that service disappears in a few hundred feet. Another camp has no service and requires a long drive to a location where we can get service. Every season my hunting partner gets his old 3 watt bag phone reconnected.

I guess what we need is a PLB that is set off by the shock of a hunter impacting the ground after falling out of his tree stand. The unit would send out it's signal with Lat/Long while connected to the hunters gps. Of course he always keeps his gps batteries fresh. And his PLB is properly maintained and has a fresh battery. I understand the life of a PLB is about 24 hours with a fresh battery. The next thing our injured hunter wakes up to a scent dog licking his face. The dogs handler is ............... :roll:

lilabner · « **Reply #4 on:** February 14, 2005, 11:43:06 AM »

We are talking sophisticated electronics here so I don't think a timer switch would pose much of an obstacle. On the other hand, the issue of false alarms is a big one and would probably weigh against manufacturing a timer device. Probably a bad idea. Just thinking out loud, which can be dangerous!

Siskiyou · « **Reply #5 on:** February 14, 2005, 01:01:59 PM »

I agree designing one with a timer should not be a problem. Currently they do not charge for false alarms from PLB's and EPIRB's. But if the false alarm rate grows like the false alarms on cars and homes I suspect they would start charging.

Just think about paying the cost of a false alarm: Helicopter $750 an hour. Manpower X cost per hour, vehicle milage, dispatchers, and the cost goes on. And the grand total breaks the bank.

Siskiyou · « **Reply #6 on:** February 21, 2005, 03:34:48 PM »

They did not know how to use their safety equipment. The press is reporting that the rescue of an avalanche victim "may have" been delayed because fellow cross country skiers did not know how to use their avalanche beacons. One skier was killed in the Sierra avalanche.