Delorme InReach

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DayTrip

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Are there any inReach users here on VFTT? I have decided to ditch my highly unreliable SPOT3 unit and get something more dependable and flexible. I wish I hadn't been so budget conscious back when I originally went the SPOT route. It seems like far more people use the SPOT but I have found mine to be far too unreliable to be worth the cost and effort and their customer service (at least on the three occasions I have emailed them) has been lousy (very long response times and idiotically simple, out of the manual suggestions that ignored what I said I have already tried in my original email).

My primary questions is this: is your inReach HIGHLY RELIABLE in the Whites, even if you are in valleys, under a decent canopy, etc? My main use for this device is to stay in contact with my wife when I am hiking and updating my location. It is my understanding that DeLorme's Iridium network is far more reliable than SPOT's network set up. The main feature I would use are the pre-canned text messages to transmit status updates while I hike. All of the GPS stuff I don't really care about because I already have a standalone GPS. What I really want is satellite text messaging but apparently there is no such device for this without all the GPS baggage.

Any feedback from someone who has an inReach and specifically utilizes the messaging features would be highly appreciated. It is a much bigger investment than the SPOT but I have some trips to Baxter and the Adirondacks planned this Summer and this device may well be my only means of communication for several days at a time and I simply do not trust the SPOT based on my experiences over the past 2 years.
 
Hmmmm. Well, I've had (the original) InReach for a couple of years. I use it to send "I'm starting to hike", "just checking in", and "I'm done for the day" messages to keep my wife off the phone with F&G. The new ones have all manner of blingy GPS stuff that like you, I'm not interested in.

I've had a few occasions where it has seemed to take a very long time for an outbound message, when I'm hiking under cover. But since I don't actually look at it to see the flashing lights while walking, I don't have any "science". I've not had problems with the start/summit/end messages, but pretty much all the time those are in clear areas (parking lots or summits). They've also done a few software updates over the years that have improved the sat link and the battery usage, and maybe my early 'long times' are simply no longer an issue.

You can pick up the "old" version used on Amazon and other places. Be aware that there are really multiple versions, depending on whether you want to pair it with the PN-60w GPS, and Android OS smartphone, or an iPhone. I always use it standalone, I didn't even own a compatible Android phone until a couple of months ago.

They just made the lowest-tier subscription ("Safety") plan a better deal (unlimited pre-canned messages, and lowered the tracking and free-form per-message cost)
 
I have only used my InReach in local dense woods tests right after I bought it, and it worked fine. But I have no other "real world" tests.

I had two Spot versions and found them both utterly useless in the woods.

I also set up my InReach as stand-alone (no smart phone), and with the minimum messaging plan.
 
Are there any inReach users here on VFTT? I have decided to ditch my highly unreliable SPOT3 unit and get something more dependable and flexible. I wish I hadn't been so budget conscious back when I originally went the SPOT route. It seems like far more people use the SPOT but I have found mine to be far too unreliable to be worth the cost and effort and their customer service (at least on the three occasions I have emailed them) has been lousy (very long response times and idiotically simple, out of the manual suggestions that ignored what I said I have already tried in my original email).

My primary questions is this: is your inReach HIGHLY RELIABLE in the Whites, even if you are in valleys, under a decent canopy, etc? My main use for this device is to stay in contact with my wife when I am hiking and updating my location. It is my understanding that DeLorme's Iridium network is far more reliable than SPOT's network set up. The main feature I would use are the pre-canned text messages to transmit status updates while I hike. All of the GPS stuff I don't really care about because I already have a standalone GPS. What I really want is satellite text messaging but apparently there is no such device for this without all the GPS baggage.

Any feedback from someone who has an inReach and specifically utilizes the messaging features would be highly appreciated. It is a much bigger investment than the SPOT but I have some trips to Baxter and the Adirondacks planned this Summer and this device may well be my only means of communication for several days at a time and I simply do not trust the SPOT based on my experiences over the past 2 years.

http://www.vftt.org/forums/showthread.php?54423-GPS-Recommendation&p=420330&viewfull=1#post420330

Some costs may be out of date though....
 
May I get geeky with you for a moment? I am a telecom engineer. Neither will be highly reliable in the Whites -- especially if you are in a valley, under canopy, etc.

The slice of the spectrum allocated for personal satcom devices is in the vicinity of 1.6 GHz -- regardless of which brand is on the cover or which satellite constellation is utilized. They all require a clear view of the sky to work properly, and they all have the same output power. A frequency that high has the benefit of being able to communicate without a lot of battery power. But a drawback is that there are more sources for interference. A device could potentially face interference from fabric (being in a pack, or a pocket), or even raindrops.

All communications systems are oversubscribed -- there are many more users than there are resources to serve the users. Satcom systems tend to be oversubscribed at a greater ratio than terrestrial-based systems. When a satcom system has more messages than it can handle, this results in messages going through very slowly, or not going through at all. Therefore, the risk of data loss does not just occur when going from the ground to the sky, or the sky to the ground -- it can also happen in the sky.

Most satcom transponders (including the GlobalStar constellation used by SPOT) use a "bent pipe" form of transmission. The processing is largely analog -- it goes up to the satellite, gets amplified, and then sent back down, as is. This also means the unwanted aspects to the signal -- including noise, etc -- are amplified and sent back down to earth. The Iridum satellites do not use this. They use regenerative transponders. The signal is IP-based. Once it is received, it is before it is sent back to earth. Digital messages can also be cached or queued in ways that analog messages cannot. This results in greater accuracy and fewer errors. It also offers more queuing options -- this means more chances for a message to go through an overused system even if the message is delayed. However, it also results in a satellite constellation that operates at a much higher cost.

There is a bit of a technological benefit to using a device homed to the Iridium constellation. However, it is still a 1.6GHz device. It still requires a clear view of the sky, and it will not work as well when this is not the case. The regenerative processing of the Iridium devices means are some where the InReach is more reliable. However, in an environment such as the Whites, these differences will be small, not large.
 
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May I get geeky with you for a moment? I am a telecom engineer. Neither will be highly reliable in the Whites -- especially if you are in a valley, under canopy, etc.

The slice of the spectrum allocated for personal satcom devices is in the vicinity of 1.6 GHz -- regardless of which brand is on the cover or which satellite constellation is utilized. They all require a clear view of the sky to work properly, and they all have the same output power. A frequency that high has the benefit of being able to communicate without a lot of battery power. But a drawback is that there are more sources for interference. A device could potentially face interference from fabric (being in a pack, or a pocket), or even raindrops.

All communications systems are oversubscribed -- there are many more users than there are resources to serve the users. Satcom systems tend to be oversubscribed at a greater ratio than terrestrial-based systems. When a satcom system has more messages than it can handle, this results in messages going through very slowly, or not going through at all. Therefore, the risk of data loss does not just occur when going from the ground to the sky, or the sky to the ground -- it can also happen in the sky.

Most satcom transponders (including the GlobalStar constellation used by SPOT) use a "bent pipe" form of transmission. The processing is largely analog -- it goes up to the satellite, gets amplified, and then sent back down, as is. This also means the unwanted aspects to the signal -- including noise, etc -- are amplified and sent back down to earth. The Iridum satellites do not use this. They use regenerative transponders. The signal is IP-based. Once it is received, it is before it is sent back to earth. Digital messages can also be cached or queued in ways that analog messages cannot. This results in greater accuracy and fewer errors. It also offers more queuing options -- this means more chances for a message to go through an overused system even if the message is delayed. However, it also results in a satellite constellation that operates at a much higher cost.

There is a bit of a technological benefit to using a device homed to the Iridium constellation. However, it is still a 1.6GHz device. It still requires a clear view of the sky, and it will not work as well when this is not the case. The regenerative processing of the Iridium devices means are some where the InReach is more reliable. However, in an environment such as the Whites, these differences will be small, not large.

Tree canopy is an issue, just like solar storms and 4km GPS resolution for plbs, but the inreach unit knows whether it's message is received it not, and perhaps it boosts it's attempt rate and it's QOS for an urgent signal. If the signal is not acknowledged, at least you have an option to bite the bullet and crawl or cut to open sky. I would speculate that the short burst transmission opens up the slant angle, especially since the satellites move pretty quickly
 
May I get geeky with you for a moment? I am a telecom engineer. Neither will be highly reliable in the Whites -- especially if you are in a valley, under canopy, etc.
Electrical engineer here. I have been playing with VHF and UHF ham radios since the 1960s and studying communication systems since then...

The slice of the spectrum allocated for personal satcom devices is in the vicinity of 1.6 GHz -- regardless of which brand is on the cover or which satellite constellation is utilized. They all require a clear view of the sky to work properly, and they all have the same output power. A frequency that high has the benefit of being able to communicate without a lot of battery power. But a drawback is that there are more sources for interference. A device could potentially face interference from fabric (being in a pack, or a pocket), or even raindrops.
Actually, 1.6GHz is a pretty good choice. (Right next to the 1.575 GHz GPS L1 frequency. GPS was designed as an all-weather military navigation system.) It is unaffected by the weather and background noise levels are pretty low. Dry pack fabric has very little effect on the signals, but wet fabric or flesh (essentially a bag of salt water...) will attenuate the signals. Rock and vegetation can absorb, diffract, and/or reflect both signals.

All communications systems are oversubscribed -- there are many more users than there are resources to serve the users. Satcom systems tend to be oversubscribed at a greater ratio than terrestrial-based systems. When a satcom system has more messages than it can handle, this results in messages going through very slowly, or not going through at all. Therefore, the risk of data loss does not just occur when going from the ground to the sky, or the sky to the ground -- it can also happen in the sky.
All communication systems have information bandwidth limits (terrestrial or satellite). A properly sized system will be overloaded only a small proportion of the time. (Most communication systems assume that only a small proportion of the users will demand service at any one time.)

Most satcom transponders (including the GlobalStar constellation used by SPOT) use a "bent pipe" form of transmission. The processing is largely analog -- it goes up to the satellite, gets amplified, and then sent back down, as is. This also means the unwanted aspects to the signal -- including noise, etc -- are amplified and sent back down to earth. The Iridum satellites do not use this. They use regenerative transponders. The signal is IP-based. Once it is received, it is before it is sent back to earth. Digital messages can also be cached or queued in ways that analog messages cannot. This results in greater accuracy and fewer errors. It also offers more queuing options -- this means more chances for a message to go through an overused system even if the message is delayed. However, it also results in a satellite constellation that operates at a much higher cost.
Bent pipe uses a simpler satellite with a more complex base station. However, if the link between the ground station and the satellite is high quality, essentially no degradation will occur on that hop. If this condition is met, a receiving ground station will receive essentially the same quality signal as the receiver in a regenerative satellite. So either system can yield the same weak ground-to-satellite signal performance.
* Advantages of the bent pipe:
- Simpler satellites
- Ability to add new kinds of signals after launch. (The satellite will simply copy the signals to the new ground-station receiver.)
* Disadvantages of the bent pipe:
- Requires simultaneous up and down links
* Advantages of regenerative:
- Data received by a satellite can be saved for later transmission
- Up and down links need not be simultaneous
- Data can be relayed to another satellite for transmission to the ground.
* Disadvantages of regenerative
- More complicated satellite
- less ability to change signal types

There is a bit of a technological benefit to using a device homed to the Iridium constellation. However, it is still a 1.6GHz device. It still requires a clear view of the sky, and it will not work as well when this is not the case. The regenerative processing of the Iridium devices means are some where the InReach is more reliable. However, in an environment such as the Whites, these differences will be small, not large.
InReach and Spot both use short burst data messages. Thus a sender only needs a link to be functional for a short period (eg through a gap in the forest cover) and the sender can keep trying until an acknowledgement is received. (This works for short messages, but not for a long continuous service such as a telephone call.)

Doug
 
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Tree canopy is an issue, just like solar storms and 4km GPS resolution for plbs, but the inreach unit knows whether it's message is received it not, and perhaps it boosts it's attempt rate and it's QOS for an urgent signal. If the signal is not acknowledged, at least you have an option to bite the bullet and crawl or cut to open sky. I would speculate that the short burst transmission opens up the slant angle, especially since the satellites move pretty quickly
Resolution for a GPS is the same whether it is in a PLB or not (~10 meters). You may be referring to the spacial resolution of a non-GPS PLB.

The advantage of the short burst messages is that the link only has to be functional for a short period and you can keep trying until you receive an acknowledgement. As local conditions change and satellite positions change, the link quality may change dramatically.

For example, there are ground-to-ground communication systems that send short high-data-rate bursts hoping that the signal will bounce off meteor trails (which can last from a fraction of a second to tens of seconds with long gaps between successive trails).

Doug
 
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Ummm ... yes ... so would I be wiser to spend my money on InReach or semaphore flags?
 
Resolution for a GPS is the same whether it is in a PLB or not (~10 meters). You may be referring to the spacial resolution of a non-GPS PLB.

The advantage of the short burst messages is that the link only has to be functional for a short period and you can keep trying until you receive an acknowledgement. As local conditions change and satellite positions change, the link quality may change dramatically.

For example, there are ground-to-ground communication systems that send short high-data-rate bursts hoping that the signal will bounce off meteor trails (which can last from a fraction of a second to tens of seconds with long gaps between successive trails).

Doug

I disagree. Check the size of the message that a GPS PLB can transmit. You will find that its resolution is in the km range, depending on latitude. There is no more space in the protocol for additional data to carr y more precise location information. Its fine for oceans and large bodies of water where an aerial or radar search can ensue; not so good for hiking.
 
I disagree. Check the size of the message that a GPS PLB can transmit. You will find that its resolution is in the km range, depending on latitude. There is no more space in the protocol for additional data to carr y more precise location information. Its fine for oceans and large bodies of water where an aerial or radar search can ensue; not so good for hiking.
While possible, it appears not to be a protocol limitation*:
http://www.sarsat.noaa.gov/emerbcns.html said:
(121.5 MHz homing beacon) This allows rescue forces to home in on a beacon once the 406 MHz satellite system has gotten them "in the ballpark" (about 2-3 miles).Some newer PLBs also allow GPS units to be integrated into the distress signal. This GPS-encoded position dramatically improves the location accuracy down to the 100-meter level
The "100-meter" figure probably refers to when selective availability was in use. (The web page is undated.) It was permanently turned off in May 2000 so the current accuracy is more likely ~10 meters.

The location accuracy from tracking the 406 MHz ground-to-satellite signal depends critically on the frequency and phase stability of 406MHz signal--poor stability will degrade the accuracy.

* FWIW, with proper protocol design it is possible to break the location data into several parts and send them in separate messages so it is technically possible to send the location in full precision. GPS does this to send the orbital info.

Doug
 
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While possible, it appears not to be a protocol limitation*:

The "100-meter" figure probably refers to when selective availability was in use. (The web page is undated.) It was permanently turned off in May 2000 so the current accuracy is more likely ~10 meters.

The location accuracy from tracking the 406 MHz ground-to-satellite signal depends critically on the frequency and phase stability of 406MHz signal--poor stability will degrade the accuracy.

* FWIW, with proper protocol design it is possible to break the location data into several parts and send them in separate messages so it is technically possible to send the location in full precision. GPS does this to send the orbital info.

Doug

Refer to https://www.cospas-sarsat.int/en/user-location-protocols... The reported position has a resolution of 4minutes. That's what Sar gets. That is in the km range for certain latitudes. I have little doubt the GPS in the plb is good to 10 meters. But it cannot convey the location to that precision.
 
Refer to https://www.cospas-sarsat.int/en/user-location-protocols... The reported position has a resolution of 4minutes. That's what Sar gets. That is in the km range for certain latitudes. I have little doubt the GPS in the plb is good to 10 meters. But it cannot convey the location to that precision.
Yes, that doc says the user location protocol has a resolution of 4 minutes (= 4 nautical mi = 7.4km N-S, less E-W).

However, if you look a little farther on that website, you will find the "standard location protocol" https://www.cospas-sarsat.int/en/st...oding-guide&id=286:standard-location-protocol which has a resolution of 4 sec which means a rounding error of at most 2 sec (~61m N-S, less E-W).

The ~61m rounding error of the standard location protocol matches the statement "This GPS-encoded position dramatically improves the location accuracy down to the 100-meter level" found in http://www.sarsat.noaa.gov/emerbcns.html and therefore a PLB/ELT/EPIRB could transmit its location with ~100-meter accuracy by using this protocol. (The allowable accuracy appears to be a legal issue: countries choose which protocols are authorized for their users: https://www.cospas-sarsat.int/en/be...ation/beacon-coding-guide-tutorial-pro?id=246)

The "more information" section on the web page for the ACR PLB-375 says
https://www.acrartex.com/products/catalog/personal-locator-beacons/resqlinkplus/ said:
With its powerful 66-channel GPS, the ResQLink+™ guides rescuers to within 100 meters or less of your position.
Thus the 100 meter accuracy is authorized for USA users. (The spec sheet gives the same 100 meter accuracy: https://www.acrartex.com/media/1374724/resqlinkplus-usa_-spec_lores.pdf)


The example given in https://www.cospas-sarsat.int/en/st...oding-guide&id=286:standard-location-protocol suggests that it uses two messages (PDF-1 and PDF-2) to gain the extra data space to send the additional resolution.


So the 100-meter accuracy is built in to the protocol, but it might have been chosen to match the ~100 meter accuracy of GPS with selective availability.

Doug
 
Here's a small amount of "real world in the Whites" data. DeLorme InReach this past weekend. I sent a few checkin-messages, all were received, and show pretty close locations.

owlloop.jpg

Other than the begin/end in the Lincoln Woods parking lot, I'm deep in the woods -- on the Franconia Brook Trail or Lincoln Brook Trail. I carry the device on the "lid" pocket on my pack, so it is transmitting/receiving through pack-cloth + trees.

The Delorme website is pretty bad for showing locations at that resolution, but when you zoom in, you can see my "going to bed" check-in and "starting to hike" at the 13 Falls Tentsite 13falls.jpg were sent from the tent-pad (on the right) and the cooking area (on the left), respectively.
 
Yes, that doc says the user location protocol has a resolution of 4 minutes (= 4 nautical mi = 7.4km N-S, less E-W).

However, if you look a little farther on that website, you will find the "standard location protocol" https://www.cospas-sarsat.int/en/st...oding-guide&id=286:standard-location-protocol which has a resolution of 4 sec which means a rounding error of at most 2 sec (~61m N-S, less E-W).

The ~61m rounding error of the standard location protocol matches the statement "This GPS-encoded position dramatically improves the location accuracy down to the 100-meter level" found in http://www.sarsat.noaa.gov/emerbcns.html and therefore a PLB/ELT/EPIRB could transmit its location with ~100-meter accuracy by using this protocol. (The allowable accuracy appears to be a legal issue: countries choose which protocols are authorized for their users: https://www.cospas-sarsat.int/en/be...ation/beacon-coding-guide-tutorial-pro?id=246)

The "more information" section on the web page for the ACR PLB-375 says

Thus the 100 meter accuracy is authorized for USA users. (The spec sheet gives the same 100 meter accuracy: https://www.acrartex.com/media/1374724/resqlinkplus-usa_-spec_lores.pdf)


The example given in https://www.cospas-sarsat.int/en/st...oding-guide&id=286:standard-location-protocol suggests that it uses two messages (PDF-1 and PDF-2) to gain the extra data space to send the additional resolution.


So the 100-meter accuracy is built in to the protocol, but it might have been chosen to match the ~100 meter accuracy of GPS with selective availability.

Doug

OK, I stand corrected... 2 of 3 possible digital location messages sent to Sarsats by epirbs elts plbs etc can report position with 4 seconds of a latitude or longitude line. The 3rd protocol only supports 4 minutes resolution and is probably not used by current generation GPS plbs
 
I carry with me the McMurdo FastFind 210 PLB. No subscription fee, lightweight & compact. It transmits directly to the international COSPAS-SARSAT international satellite network. According to their materials a GPS location is embedded in the 406 MHz giving a precision within meters. Since it's a PLB it has a secondary 121.5 MHz homing signal for SAR to use once they're in the vicinity. The GPS positioning, & I imagine the 406 MHz signal can be inhibited by tree cover, cliffs, canyon walls, but I would assume that you're not going to find anything that works better than a PLB. The downside is that I can't send an "I'm OK signal," but my family knows that if they haven't been contacted by SAR, then I'm OK, or I've fallen of a cliff.

The FastFind 210 is no longer made, but you can get its successor, the FastFind Ranger at MEC. REI sells its competitor, the ACR ResQLink+. If you really feel compelled to send back messages, ACR's AquaLink View 406 allows you to send "I'm OK" messages to preprogrammed emails, with a subscription plan.
 
The 3rd protocol only supports 4 minutes resolution and is probably not used by current generation GPS plbs
And I learned that the GPS location is limited to 4 sec resolution (~100 meter accuracy).

It appears to depend on the country--some allow only the lower resolution by restricting users to the user location protocol (4 min resolution). https://www.cospas-sarsat.int/en/be...ation/beacon-coding-guide-tutorial-pro?id=246

Some countries require a license and some prohibit use. See https://www.acrartex.com/media/1374729/y1-03-0251-1e.pdf pg 5 for a list.

Doug
 
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I carry with me the McMurdo FastFind 210 PLB. No subscription fee, lightweight & compact. It transmits directly to the international COSPAS-SARSAT international satellite network. According to their materials a GPS location is embedded in the 406 MHz giving a precision within meters.
I think that we have established a best accuracy of ~100 meters by now...

Since it's a PLB it has a secondary 121.5 MHz homing signal for SAR to use once they're in the vicinity. The GPS positioning, & I imagine the 406 MHz signal can be inhibited by tree cover, cliffs, canyon walls, but I would assume that you're not going to find anything that works better than a PLB. The downside is that I can't send an "I'm OK signal," but my family knows that if they haven't been contacted by SAR, then I'm OK, or I've fallen of a cliff.
Both the 121.5 MHz and 406 MHz signals will be affected by the local vegetation and topography but less so than the ~1.6 GHz signals used by SPOT and InReach. The 100 meter accuracy of the GPS position should get rescuers within range of the 121.5 MHz and the (direct) 406 MHz signals in almost all cases (except maybe under salt water or in a cave...).

I agree--a PLB probably has the best chance of getting word out to rescuers. However, the ability to compose and send messages can also be very valuable--you can tell rescuers what you need and how soon. Or call them off... (FWIW I have presided at two different accident scenes and in both cases I was able to tell the rescuers what was needed before they started out.)

Doug
 
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