Mandown in the Backcountry

[repeaterepeater]

Hi all. I have a few Motorola XPR7550e (VHF) units with Radio Man Down entitlements. Just to mention, I have no other infrastructure other than the portables.

Spending time in the wilderness has it's risks and I'm trying to find reasonable ways to use modern technology to minimize these risks. As such, my goal is to see if there is a way to employ the features of the XPR7550e to transmit or even detect distress.

Imagine a group of backcountry skiers and a scenario where one member of the group is separated and suffers an injury. Whether manually activated by pressing the emergency button atop the unit, or by automatic detection via the Man Down settings, I want to see if the unit in possession of the party in distress can (a) initiate an intermittent audible alert to aide the others in discovering their location, (b) transmit an audible alert to the other radios in the group to draw their attention to the emergency condition, and (c) use GPS feature of the radio to transmit a text message to the other radios in the group indicating the victim's last known GPS coordinates.

This sounds like a pretty practical use case for anyone from outdoor excursion operators, to forestry professionals, to wildfire prevention teams, etc. There must be a way to do this!

Thanks in advance for considering and responding to my post. In case it is useful to know, I'm running CPS 16.0 (Build 828). In terms of my skill level, I've tinkered with the Man Down settings and understand enough to get it to initiate the alert tones when triggered. But I know very little about setting up a group of radios with individual IDs, anything to do with radio-to-radio data or messaging, etc. So...in terms of CPS, treat my as a novice (and go easy on me!) Thanks and Happy Holidays.

 

[K2NEC]

Yes, 2 of those 3 things are possible by programming of the radios. Im not sure about the GPS function however I don't believe there is a way to transmit GPS locations to other portables. Just be aware of the range limitations for potable-to-potable coverage. Depending on terrain you may not get more than a mile or 2 of reliable communications coverage.

 

[repeaterepeater]

K2NEC: Thanks for kicking this off.

The range isn't a real issue in our case, as it would be very rare to be separated by a distance in excess of what you note. Unless the terrain necessitates that we not stop (such as descending down a pitch with an extreme grade), we typically pause at intervals to make sure everyone is accounted for. What's more, we're ascending/descending the same face of hill, mountain, etc., so a large feature, like a mountain itself, usually doesn't factor in as an obstruction.

Getting those GPS coordinates, though, would be clutch. For example, imagine the distress call is triggered when you're motoring down the mountain and don't actually hear it. As long as coordinates got fired off early enough that you were still within range, you'd have it in a message log. As much effort as it would be to head back uphill, at least you'd have a destination to head toward.

Speaking of messages, I have to do some homework to understand the basic architecture and settings to permit radio-to-radio text messaging. It's a totally unknown are of knowledge for me. I'm open to any advice is on where to start on this topic. If I'm having trouble figuring it out, that may be my second-ever post in the forums here!

 

[W9WSS]

Correct me if I'm wrong, but don't the radios have to be in digital mode enabled for GPS and text messaging? Or can the XPR7550e do GPS and text messaging in analog mode?

 

[Firebuff880]

@repeaterepeater as @K2NEC said you can do Mandown and Emergency. The person caring the radio can look at the GPS data Enabled in the Menu options of CPS. But there is no firmware based way to send the location or ask the location of a subscriber with out an application server of some form. The only exception to that might be if you had someone develop a custom solution that you load on the Generic Option Board GOB of each subscriber..

The GOB skill set is limited within the ADP community and does not come cheap..

 

[K2NEC]

@W9WSS Correct, text messaging only works in DMR.

@repeaterepeater If I may offer a suggestion, program the radios with the audible alert which would admit an audible beacon that tells where the mandown radio is. In the event of an avalanche or something similar where the person is down and they can't get up, this would be beneficial in aiding to the location of the person. I am also going to suggest that you get speaker mics with the emergency buttons on them (PMMN4025, PMMN4062) for a few reasons. The mandown button on the XPR7550e is rather small and difficult to get to with a gloved hand. With the emergency button on the mic you can easily navigate to the button and can be pressed even with a glove on. Also this allows you to keep the radio in a pocket and all you need to do is run the speaker mic to an external part of your jacket. Both mics will also withstand moisture relatively well, i've used them in snow and rain without any issues.

 

[cmjonesinc]

I too carry my radio when outdoors and with a group to stay in touch. While I can definitely see those radio functions being useful within the group for the limited area a protable covers, I would highly recommend getting a PLB as well. I often try to find radio traffic while hiking and attempt to make contacts on repeaters and nearly always go unanswered red. I would hate to have my life riding on the hopes that I could get an answer on a radio when a PLB is almost guaranteed to work all of the time.

 

[repeaterepeater]

@cmjonesinc Good suggestions.

In terms of the PLB, I like the idea. When the actual scenario is about snow sports, I always have an avalanche transceiver, which for all intents and purposes is only a "near-field" communication device. And regardless of season, I usually have an Iridium phone as well. While a sat phone doesn't share coordinates like a PLB, the key shortcoming of the PLB is getting the data to the most likely rescuers (i.e. the companions on the journey). If a rescue is indeed necessary, time is of the essence and gaining access to the PLB data in the field is usually impossible. These are often places with no cellular voice or data.

@Firebuff880 Most of what I've been told offline is in keeping with your comments, namely that I need a server to achieve my goals. Hard to have this sort of infrastructure as a recreationalist, let alone one that seeks far off places devoid of...infrastructure! In googling around, I found a product called Sprite TW251, which appears to be a piece of code that sits on the radio's expansion board. While the 2-page brochure I read seems promising, it warrants further research to confirm it would do what I want here.

 

[jeepsandradios]

Buy an Inreach if you are worried. The radio wont do what you want.

 

[Stretchman]

Things like this are where the Yeasu Fusion system shines. Group mode, along with xmitted gps coordinates and bearing plus distance work well in these units. But, alas, they do not have a man down feature. Some of the other dmr radios have distance unit to unit, ip67, and have the man down feature as well, because part 90. But, they're not motorola.

So yeah, you guessed it. Why they don't listen to us and make what we would want and pay for, right. No unit does it all. Not for nothing, but in a situation like man down, trying to decode gps coordinates would be a hassle.

The do make some GMRS radios that have direction and distance, but, again, no man down feature that I am aware of. They might have an emergency key.

Ask for it and maybe they'll make it, right. Yeah, maybe. I wouldn't hold my breath.

 

[repeaterepeater]

Thanks everyone for the thoughts and suggestions! This being my first post on here, and having gotten so many thoughtful responses so quickly, I'm very appreciative. This is a testament to the curious and collaborative nature of the radio-tinkering community!

Happy Holidays!

 

[Firebuff880]

@repeaterepeater

I believe you will find that the "Sprite TW251" is a dated product and everything it did is now in the Firmware for Lone Worker, Man Down and Emergency. We have done Crash Detection, indoor GEO Fencing and even QC-II Paging style extensions for the TRBO subscribers with GOB code, but we have not had a business case ($$s) to look at the GPS data in the subscriber at the subscriber level.

Also, of NOTE: The All Call built into the TRBO platform does NOT support data messaging so use a Group other than 255 for your project.

 

[repeaterepeater]

As a complete aside, I have very little understanding of how to implement private calls or send text messages between portables (either in terms of CPS settings or at the unit, once the settings are in). What's more, I can't seem to find a good tutorial on the basic concepts, and how to execute them on any YouTube videos, on this forum, etc. If anyone could be kind enough to point me in the right direction so that I can learn more, I'd be grateful.

 

[K2NEC]

I think there are a few good youtube videos on general programming but if you have any specific questions, feel free to PM me.

 

[ko6jw_2]

This type of thread comes up here frequently. I strongly suggest something like a Garmin Inreach+. Even if you can contact others via an HT, who can they contact to summon help? I have been in places in Alaska where there was no cell service, no ham repeaters and no commercial two-way service even though our truck was radio equipped. A distress beacon would have been the only hope of calling for assistance.

Yes, there is a cost to buy and subscribe to these services. How much is your life worth? Or, the lives of your friends. Don't get me wrong, I'm a ham and I have a GMRS license. I would not rely on either one in case of an emergency.

 

[mmckenna]

I know this can be done on NXDN using the 'emergency' function. It'll key up the radio, send Lat/Lon/Elevation, radio ID, and even hold the mic open so you can hear what's going on. I think it can even be triggered by the man down function, but never tried.

But that requires someone reading the Lat/Lon off the radio screen, then typing that into the GPS.

Might be an option. Might work well. Might not. If everyone is equipped with a radio, and someone grabs the lat/lon quick enough.
But range would be a limitation.
You can do the same thing with the Garmin Rino a lot easier, plus it actually maps it out on the screen.

And +1 on the Garmin InReach. I carry one when working at remote sites. $12/month is cheap insurance, plus that includes some free messages, so I can periodically send check in messages to the wife.

 

[vagrant]

"Man down" could definitely have polarization concerns as well as body interference. Five watts could become 0.01 watts, plus body or pack interference and terrain. Perhaps three blasts using a whistle in case the radio is damaged, or is no longer in reach of the operator or via RF to others.

A Whistle - Saving people that knew better while others perished for thousands of years.

 

[KN4EHX]

In theory it all sounds good, but as many have pointed out, InReach is probably more appropriate for this type situation. The radio is a useful tool for sure, but it’s only useful if someone is listening for you.

I’d suggest having some calling frequencies in the programming and federal interop channels. Overall a handheld radio as your only life line is an excellent advantage, but it is still a shot in the dark. As suggested, a whistle goes a very long way and probably serves as a means of blowing off some frustration since there is a gratification of loud sound. A signal mirror is probably not a bad ideal and the polished metal ones are very light weight while being useful in other fashions. Still not too much good if you’re buried under an avalanche. I’d add in whatever SAR frequencies are being used in your AO. In a Life or death situation the gloves are off and so are band plans.

The universal 3 blows of a whistle, 3 flashes of a light, or about 3 of anything to signal an emergency has probably saved a lot of bacon.

Perhaps APRS might not be a bad ideal, but there is a fine line between practical and too much weight. Above all else tell someone where you plan to go and when to expect your return.

 

[KN4EHX]

Is there a particular region or state you plan to go skiing? I realize you said imagine, but usually there is some truth to these scenarios.

As others mentioned don’t bet your life on ham radio, but in my world of public service I actually had to use ham radio on one occasion due to not being able to hit any government repeaters and no cell service. Once I said declaring an emergency I had like 3 people on the other end. 2 meter calling, you might not hear the other person, but they might still hear you. I’d definitely add the VTAC channels into a separate zone and the marine band too. You’d be surprised how many people are listening but not speaking.

 

[speedway_navigator]

Imagine a group of backcountry skiers and a scenario where one member of the group is separated and suffers an injury.

I'd rather imagine me twisting an ankle while jogging on the beach where a bunch of girls would come to my aid.

Hytera can do all 3, sound an alarm on the sending radio speaker, activate alarms on other radios and send GPS with the alarm.
(Not sure if the H series can do #4, attract the girls)