Jonathan,
Read your previous DSP/Pulse/S1 review on another website, sent you a PM on TGR, and then saw this on Lou’s site. I will repeat the gist of my PM:
You did not mention anything about deep burials in your previous review. Do three antaenae beacons help with deep burials? Do you discuss this in the reviews to come on Lou’s site? Can you refer me to any other sources of info on this?
I think Couloir did a beacon techinique article on deep burials a few years before it shut down, but I can’t find it now. Anyone know of any online sources of old Couloir articles? You could access back issues of Couloir from the old Couloir website, but I can’t find them on the merged Backcountry website.
I am asking because our SAR team has a budget to upgrade our fleet of Trackers, and I am doing preliminary research on what to buy.
Here’s a very detailed exposition on the subject: http://www.beaconreviews.com/transceivers/Spikes.htm
(Also lots of other good material there, though my approach to beacon reviews is to provide the information and let the prospective purchaser decide, rather that give numerical ratings.)
My (far more brief) take is:
– If a beacon has less than three antennas, you are almost certain to experience at least some amount of incorrect readings during the pinpointing phase. Hence, a third antenna is a benefit for any depth of burial.
– Contrary to the findings there, in my tests, the D3 and X1 eliminated nulls and spikes when they were within 2.0 meters (as indicated on their distance indicator, which of course is not necessarily the actual distance for any beacon), but were subject to nulls/spikes just outside of that distance (and much further out such nulls/spikes to do not occur for any beacon). I did this by identifying the places at which a two-antenna registered incorrect readings (with the transmitting beacon on the surface, and the searching beacon at about waist level), and then saw how the D3 and X1 performed over that same range.
– I have not tested the Patroller (i.e., basically renamed X1) and the latest D3, so I still have to verify whether the point has changed at which the third antenna is activated. (This will be clarified in the upcoming review series.)
Matt KinneyNovember 12, 2008 - 12:48 pm
Once again John your reviews on beacons on are outstanding and not based on blind allegiance due to sponsorship and/or “bro” deals…Thanks for your “volunteer” effort and dedication to the topic.
Cheers .. Matt
“mechanized ascension ” ..that’s funny!
nitsujNovember 12, 2008 - 2:06 pm
Looking forward to this. Seems like most of the data out there is hearsay or reeks of being funded by one co. or the other.
GregNovember 12, 2008 - 5:06 pm
I’m looking forward to reading the reviews. As an electrical engineer I’m curious what it is about iPods which create such interference? 457kHz is well outside the audio band of the iPod, and as far as I know the non-touch iPods have no RF transmitter.
I’m pretty curious about the iPod issue myself, having a modicum of knowledge about radio stuff.. perhaps it’s a harmonic or something, from some RFI that comes from the iPod even though it doesn’t have a transmitter? Would be easy to check with a frequency checker. I know some hams with those, all I need is an iPod and could easily check for RFI.
Paul S.November 12, 2008 - 10:29 pm
Any electronic device that is not designed to specifically avoid it will put out radiation at lots of frequencies. Any battery-powered audio devices such as the iPod designed in the last 10 years will use a switching power amplifier (technically called a “Class-D amplifier”) which may use a switching frequency anywhere from 30kHz up to several hundred kHz, and this frequency may change over time. The problem is that a harmonic of the switching frequency could fall on top of the signal from the beacon. The only way to make sure this is not the case is for the device designer to spend a significant amount of money and testing to avoid this frequency. This is why devices that are designed to be used in sensitive environments cost a lot more money; not due to the manufacturing, but due to the extra design and testing.
Hope this clarifies the risk associated with using other electronic devices in proximity to an avalanche beacon.
Thanks,
Paul
coryNovember 13, 2008 - 10:45 am
Couple of Q’s-
-What about the otorvox M2? I’ve had one for 5 years and love it! It works well for me, but I just wanted your thoughts.
-How often should a beacon be sent back to the company for a test/recallibration? What are the different companies policies on this?
Re iPod, thanks for everyone’s feedback. Of all the devices I tested, it was the only one to interfere with all brands of beacons, and enough to totally mess up a search for a user who didn’t realize that it was still on. (Fortunately I never have to worry about that since all my partners listen instead to my detailed expositions on the merits of Dynafits and Gu . . . or are they really listening to me?)
Re M2 (and very similar predecessor M1), definitely a highly innovative design, and certainly appeals to those with well-practiced analog search skills who still want the benefits of very long range and analog acoustics, but also want the benefits of visual indicators via digital processing for signal strength/distance, alignment with flux line, and whether the volume/sensitivity should be increased or decreased.
However, with only one antenna, it is not a directional beacon. Now, granted, it is the next best thing, since it will tell you whether you’re going in the correct direction (as well as about how far away you are), but if you’re not going in the correct direction, it won’t tell you whether to go left or right. This was the Tracker’s big breakthrough, and it still remains a critical advantage of any multiple-antenna beacon.
I am concerned that many people will buy an M2 (often used) then are lulled into lack of practice because it’s a “digital” beacon. (Yes, even a directional beacon should require regular practice, but let’s face it, you can get away more easily with being out of practice.) For example, my otherwise responsible local biking and skiing partner, a backcountry newbie, took the same avy course I was teaching last year. During the beacon practice session, I was rather distressed to discover that he was pretty much incompetent. (You’d think he’d take have taken advantage of knowing me to get in some practice!)
Re maintenance, separate post coming up soon on that…
Okay, maintenance info. First, a DSP can test the frequency drift for any beacon, and an S1 can test frequency, transmission period, and total cycle time, so helpful to have those beacons around for testing other beacons.
Also, warranty is five years, except for Pieps Freeride’s two years.
I’ll include some add’l info below that might be of interest to prospective buyers of used beacons.
Barryvox Opto 3000
– The later (and much beloved) versions were in a red housing, and marketed/labeled by Mammut. But an earlier version was in a blue housing, and marketed/labeled by Red – these had much slower processing.
Barryvox Pulse
– Runs self-test upon start-up.
– Recommended functional test at service center every five years. How to tell your three years are up? Yes, of course, in keeping with the Pulse’s theme, the date is accessible from the menu.
– Can also combine test with firmware upgrade.
BCA Tracker
– I don’t see anything in the user manual re period testing.
– I have heard quite a few reports of failure in older models, i.e., oval housing, microwave-style membrane buttons, all-strap harness. When no longer under warranty, BCA offers a new beacon for around $180.
– Even older versions had auto-revert the default upon start-up, and had an overly stretchy all-strap harness.
Ortovox
– Free inspection service within five years of manufacture. See seal in battery compartment with quarter (roman numerals) and two-digit year.
– After that, service recommended every two years (at a fee).
– Old F1 beacons seem especially prone to frequency drift, or maybe I’ve just had the opportunity to test lots of old F1, some so drifted they were impossible to find.
– Old M1 and M2 beacons start to lose LCD sections from their stacked flux line alignment display. I’ve also seen one M2 had its on/off switch get stuck.
– Old X1 beacons lacked a third antenna, and the very first generation had very slow processing. I’ve also seen an X1 fail entirely (although it had been subject to lots of abuse).
– S1 inspection can also be combined with firmware upgrade.
Pieps DSP
– Runs a self-test upon start-up so sophisticated that it searches for its own signal (which means you need to keep it away from other beacons, or else it senses multiple signals and will return an error message, although it will still function fine).
– Pieps has come out with firmware upgrades once a year recently, some significantly, some fairly minor. With each firmware upgrade ($20 at Liberty Mountain, plus postage to them, although other services centers can do this too), a test is performed, complete with detailed printout of results.
Unhappy CamperNovember 13, 2008 - 6:21 pm
Lou,
I think your comment about not trusting someone with an analog beacon without a gray beard was a bit unfair. I do feel practice with a beacon, digi or otherwise, can mean the difference between life or death. I won’t argue that practice with a digital beacon is probably the best of both worlds, but that isn’t exactly how you put it.
Jonathan’s comment, “For example, my otherwise responsible local biking and skiing partner, a backcountry newbie, took the same avy course I was teaching last year. During the beacon practice session, I was rather distressed to discover that he was pretty much incompetent. (You’d think he’d take have taken advantage of knowing me to get in some practice!)” sums up my point nicely.
Unhappy Camper, that’s Jonathan’s take and your disagreement is duly noted. I’m actually the greybeard, and am comfortable using an analog beacon, though I use a Tracker as does the rest of my family, as I believe these are far superior to analog, especially in a panic situation. Jonathan, what say you?
The gray beard comment is mine (or rather, my approving repetition of someone else’s comment), so I’ll take any heat for it.
More elaborately, when I see someone with an F1 or M2 (or more rarely, Pieps Optifinder/Opti4 or SOS), my reaction is that the person is:
– an old-timer who is very skilled with a single-antenna beacon (personally I’ve never come across one of these, although I’m sure they exist);
– more likely, an old-timer who *thinks* he is very skilled with a single-antenna beacon, but really is much worse than a kid handed a Tracker (or D3) and given only several seconds of instruction; or,
– even more likely, a newbie who bought one on the cheap and is unlikely to ever put in the far more extensive practice that is necessary just to become competent at even a single-burial search (e.g., my local partner, or the dozens of posters at TGR who have bought an F1 from a big used batch from a construction company this year or a mechanized bc ops last year).
Another problem for newbies with single-antenna beacons is that their partners with multiple-antenna designs are going to ready almost immediately to progress to practice with multiples and deep-burial pinpointing, along with strategic shoveling and other elements of the rescue process. (Meanwhile, I’m going to pressure my partner to replace his M2 with something else…)
13 comments
Jonathan,
Read your previous DSP/Pulse/S1 review on another website, sent you a PM on TGR, and then saw this on Lou’s site. I will repeat the gist of my PM:
You did not mention anything about deep burials in your previous review. Do three antaenae beacons help with deep burials? Do you discuss this in the reviews to come on Lou’s site? Can you refer me to any other sources of info on this?
I think Couloir did a beacon techinique article on deep burials a few years before it shut down, but I can’t find it now. Anyone know of any online sources of old Couloir articles? You could access back issues of Couloir from the old Couloir website, but I can’t find them on the merged Backcountry website.
I am asking because our SAR team has a budget to upgrade our fleet of Trackers, and I am doing preliminary research on what to buy.
Here’s a very detailed exposition on the subject:
http://www.beaconreviews.com/transceivers/Spikes.htm
(Also lots of other good material there, though my approach to beacon reviews is to provide the information and let the prospective purchaser decide, rather that give numerical ratings.)
My (far more brief) take is:
– If a beacon has less than three antennas, you are almost certain to experience at least some amount of incorrect readings during the pinpointing phase. Hence, a third antenna is a benefit for any depth of burial.
– Contrary to the findings there, in my tests, the D3 and X1 eliminated nulls and spikes when they were within 2.0 meters (as indicated on their distance indicator, which of course is not necessarily the actual distance for any beacon), but were subject to nulls/spikes just outside of that distance (and much further out such nulls/spikes to do not occur for any beacon). I did this by identifying the places at which a two-antenna registered incorrect readings (with the transmitting beacon on the surface, and the searching beacon at about waist level), and then saw how the D3 and X1 performed over that same range.
– I have not tested the Patroller (i.e., basically renamed X1) and the latest D3, so I still have to verify whether the point has changed at which the third antenna is activated. (This will be clarified in the upcoming review series.)
Once again John your reviews on beacons on are outstanding and not based on blind allegiance due to sponsorship and/or “bro” deals…Thanks for your “volunteer” effort and dedication to the topic.
Cheers .. Matt
“mechanized ascension ” ..that’s funny!
Looking forward to this. Seems like most of the data out there is hearsay or reeks of being funded by one co. or the other.
I’m looking forward to reading the reviews. As an electrical engineer I’m curious what it is about iPods which create such interference? 457kHz is well outside the audio band of the iPod, and as far as I know the non-touch iPods have no RF transmitter.
I’m pretty curious about the iPod issue myself, having a modicum of knowledge about radio stuff.. perhaps it’s a harmonic or something, from some RFI that comes from the iPod even though it doesn’t have a transmitter? Would be easy to check with a frequency checker. I know some hams with those, all I need is an iPod and could easily check for RFI.
Any electronic device that is not designed to specifically avoid it will put out radiation at lots of frequencies. Any battery-powered audio devices such as the iPod designed in the last 10 years will use a switching power amplifier (technically called a “Class-D amplifier”) which may use a switching frequency anywhere from 30kHz up to several hundred kHz, and this frequency may change over time. The problem is that a harmonic of the switching frequency could fall on top of the signal from the beacon. The only way to make sure this is not the case is for the device designer to spend a significant amount of money and testing to avoid this frequency. This is why devices that are designed to be used in sensitive environments cost a lot more money; not due to the manufacturing, but due to the extra design and testing.
Hope this clarifies the risk associated with using other electronic devices in proximity to an avalanche beacon.
Thanks,
Paul
Couple of Q’s-
-What about the otorvox M2? I’ve had one for 5 years and love it! It works well for me, but I just wanted your thoughts.
-How often should a beacon be sent back to the company for a test/recallibration? What are the different companies policies on this?
Re iPod, thanks for everyone’s feedback. Of all the devices I tested, it was the only one to interfere with all brands of beacons, and enough to totally mess up a search for a user who didn’t realize that it was still on. (Fortunately I never have to worry about that since all my partners listen instead to my detailed expositions on the merits of Dynafits and Gu . . . or are they really listening to me?)
Re M2 (and very similar predecessor M1), definitely a highly innovative design, and certainly appeals to those with well-practiced analog search skills who still want the benefits of very long range and analog acoustics, but also want the benefits of visual indicators via digital processing for signal strength/distance, alignment with flux line, and whether the volume/sensitivity should be increased or decreased.
However, with only one antenna, it is not a directional beacon. Now, granted, it is the next best thing, since it will tell you whether you’re going in the correct direction (as well as about how far away you are), but if you’re not going in the correct direction, it won’t tell you whether to go left or right. This was the Tracker’s big breakthrough, and it still remains a critical advantage of any multiple-antenna beacon.
I am concerned that many people will buy an M2 (often used) then are lulled into lack of practice because it’s a “digital” beacon. (Yes, even a directional beacon should require regular practice, but let’s face it, you can get away more easily with being out of practice.) For example, my otherwise responsible local biking and skiing partner, a backcountry newbie, took the same avy course I was teaching last year. During the beacon practice session, I was rather distressed to discover that he was pretty much incompetent. (You’d think he’d take have taken advantage of knowing me to get in some practice!)
Re maintenance, separate post coming up soon on that…
Okay, maintenance info. First, a DSP can test the frequency drift for any beacon, and an S1 can test frequency, transmission period, and total cycle time, so helpful to have those beacons around for testing other beacons.
Also, warranty is five years, except for Pieps Freeride’s two years.
I’ll include some add’l info below that might be of interest to prospective buyers of used beacons.
Barryvox Opto 3000
– The later (and much beloved) versions were in a red housing, and marketed/labeled by Mammut. But an earlier version was in a blue housing, and marketed/labeled by Red – these had much slower processing.
Barryvox Pulse
– Runs self-test upon start-up.
– Recommended functional test at service center every five years. How to tell your three years are up? Yes, of course, in keeping with the Pulse’s theme, the date is accessible from the menu.
– Can also combine test with firmware upgrade.
BCA Tracker
– I don’t see anything in the user manual re period testing.
– I have heard quite a few reports of failure in older models, i.e., oval housing, microwave-style membrane buttons, all-strap harness. When no longer under warranty, BCA offers a new beacon for around $180.
– Even older versions had auto-revert the default upon start-up, and had an overly stretchy all-strap harness.
Ortovox
– Free inspection service within five years of manufacture. See seal in battery compartment with quarter (roman numerals) and two-digit year.
– After that, service recommended every two years (at a fee).
– Old F1 beacons seem especially prone to frequency drift, or maybe I’ve just had the opportunity to test lots of old F1, some so drifted they were impossible to find.
– Old M1 and M2 beacons start to lose LCD sections from their stacked flux line alignment display. I’ve also seen one M2 had its on/off switch get stuck.
– Old X1 beacons lacked a third antenna, and the very first generation had very slow processing. I’ve also seen an X1 fail entirely (although it had been subject to lots of abuse).
– S1 inspection can also be combined with firmware upgrade.
Pieps DSP
– Runs a self-test upon start-up so sophisticated that it searches for its own signal (which means you need to keep it away from other beacons, or else it senses multiple signals and will return an error message, although it will still function fine).
– Pieps has come out with firmware upgrades once a year recently, some significantly, some fairly minor. With each firmware upgrade ($20 at Liberty Mountain, plus postage to them, although other services centers can do this too), a test is performed, complete with detailed printout of results.
Lou,
I think your comment about not trusting someone with an analog beacon without a gray beard was a bit unfair. I do feel practice with a beacon, digi or otherwise, can mean the difference between life or death. I won’t argue that practice with a digital beacon is probably the best of both worlds, but that isn’t exactly how you put it.
Jonathan’s comment, “For example, my otherwise responsible local biking and skiing partner, a backcountry newbie, took the same avy course I was teaching last year. During the beacon practice session, I was rather distressed to discover that he was pretty much incompetent. (You’d think he’d take have taken advantage of knowing me to get in some practice!)” sums up my point nicely.
Unhappy Camper, that’s Jonathan’s take and your disagreement is duly noted. I’m actually the greybeard, and am comfortable using an analog beacon, though I use a Tracker as does the rest of my family, as I believe these are far superior to analog, especially in a panic situation. Jonathan, what say you?
The gray beard comment is mine (or rather, my approving repetition of someone else’s comment), so I’ll take any heat for it.
More elaborately, when I see someone with an F1 or M2 (or more rarely, Pieps Optifinder/Opti4 or SOS), my reaction is that the person is:
– an old-timer who is very skilled with a single-antenna beacon (personally I’ve never come across one of these, although I’m sure they exist);
– more likely, an old-timer who *thinks* he is very skilled with a single-antenna beacon, but really is much worse than a kid handed a Tracker (or D3) and given only several seconds of instruction; or,
– even more likely, a newbie who bought one on the cheap and is unlikely to ever put in the far more extensive practice that is necessary just to become competent at even a single-burial search (e.g., my local partner, or the dozens of posters at TGR who have bought an F1 from a big used batch from a construction company this year or a mechanized bc ops last year).
Another problem for newbies with single-antenna beacons is that their partners with multiple-antenna designs are going to ready almost immediately to progress to practice with multiples and deep-burial pinpointing, along with strategic shoveling and other elements of the rescue process. (Meanwhile, I’m going to pressure my partner to replace his M2 with something else…)
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