Woops--typo. That really looks like the way to go. I'm not allergic to soldering.
Recommendations for easy-to-use tracking device for total newb with no smartphone.
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Woops--typo. That really looks like the way to go. I'm not allergic to soldering.
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This is my personal recommendation chart, not a comprehensive list. It's focused on the lowest-cost complete systems so I didn't include ones you have to build. I'll check out the Aim XTRA site and add links to it and the Eggfinder to my article.
Uh oh! Next question. The FAQ for the Eggfinder says that you need to keep it away from things that are conductive, which means it doesn't go in your AV bay. They recommend putting it in your nose cone.
This raises two questions:
This raises two questions:
- How on earth do you install it in the nose cone?
- It seems to me that one of the most common recovery issues is when the upper shock cord breaks/burns and the nose cone separates. In that case, you find your nose cone, but lose the expensive parts of your rocket. I guess that's not a question.
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You make a little sled for it. See my video on making a nose cone bay.
Here's a TeleGPS in my 54mm Defender MKIII:
And here's a Real Flight Systems GPS-1 in my Solar Sailer II upscale:
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If your airframe is made of carbon fiber or aluminum, then you do need to put any radio gear in the nose. Otherwise, it's a convenient place, but not necessary. (I'm not familiar with the Eggfinder specifically, but I would go with their recommendations if you use their unit.)
Well, looking at the amount of assembly required for the Eggfinder, and also the nose cone modifications, I'm now feeling like it would be more cost effective to go with the BRB900. Does anyone know if that can go in the altimeter bay (provided there's room)?
Can you plug those same latitude/longitude readings into Google maps on an IPhone ?
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Yup, or whatever app you use. I personally use MotionX, some of the mapping apps don't like not having Internet access. Not much use for it where I fly, it's all dry lake bed so there aren't any usable landmarks on the map per se.
BTW, my recommendations regarding keeping the antenna away from metallic bits pretty much holds for all trackers, although the 70 cm Ham band trackers are a bit less susceptible to interference issues than the 900 MHz units because of the longer wavelength. The nose cone tends to be a convenient place to mount trackers because the shape works well with an antenna, and they generally don't have a lot of metal in them. A metal tipped antenna is most likely not going to be a problem, because it's at the tip of the antenna where there's very little output anyway.
BTW, my recommendations regarding keeping the antenna away from metallic bits pretty much holds for all trackers, although the 70 cm Ham band trackers are a bit less susceptible to interference issues than the 900 MHz units because of the longer wavelength. The nose cone tends to be a convenient place to mount trackers because the shape works well with an antenna, and they generally don't have a lot of metal in them. A metal tipped antenna is most likely not going to be a problem, because it's at the tip of the antenna where there's very little output anyway.
Is it just that it shouldn't touch the metallic parts, or that it needs to be X inches away from them?
This is important to me, because I am thinking like this:
Anyone?
This is important to me, because I am thinking like this:
- Eggfinder: low cost but lots of work, and if I screw something up, I'm out the cost savings anyway, needs to go in the nose cone, meaning I have to do a lot more customization of the rocket before I can get it to the field.
- BRB900: high cost, but works out of the box. If it doesn't need to go in a nose cone, then I'm sold.
Anyone?
bill2654
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The Eggfinder isn't "a lot of work". I assembled mine in a matter of hrs. without any previous experience. You can modify a NC in an no time. It took me no more than 4 to 5 hrs. total. For me it was well worth the savings.
That's a great photo Bill2654. It shows everyone one would need to duplicate/copy/steal/plagiarize....
I fly mn brb900 in 4" and 3" bays with two altimeters wedged in there.
I understand it's not recommended. In my experiences it works. It's only three flights on two separate days., but all flights tracked and deployed without issue.
it also outputs some cool 3d tracks. My 4" quick and dirty on a pair of I200W's to 2963', and my Darkstar to 6850' on a K805G (i seem to have forgotten to clear the flash between flights, and the weird line away from the field is because I forgot to unplug the tracker after I flew quick and dirty, just tossed it in the car and drove home...track goes for 50 miles...opps.). Also of note - the BRB900 went into the drink with my darkstar. The altimeters died.... BRB900 came back to life after drying out. The cost is higher. the eggfinder is interesting and I may try one. But the BRB900 works, easily and without effort.
It doesn't -need- to go in the nose.... but I'll likely put it there in the future, mostly for space reasons, and all my 3" birds have av-bays in the nose anyways. If you're worried about losing the nose from the body.... build a better recovery harness.
I understand it's not recommended. In my experiences it works. It's only three flights on two separate days., but all flights tracked and deployed without issue.
it also outputs some cool 3d tracks. My 4" quick and dirty on a pair of I200W's to 2963', and my Darkstar to 6850' on a K805G (i seem to have forgotten to clear the flash between flights, and the weird line away from the field is because I forgot to unplug the tracker after I flew quick and dirty, just tossed it in the car and drove home...track goes for 50 miles...opps.). Also of note - the BRB900 went into the drink with my darkstar. The altimeters died.... BRB900 came back to life after drying out. The cost is higher. the eggfinder is interesting and I may try one. But the BRB900 works, easily and without effort.
It doesn't -need- to go in the nose.... but I'll likely put it there in the future, mostly for space reasons, and all my 3" birds have av-bays in the nose anyways. If you're worried about losing the nose from the body.... build a better recovery harness.
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CarVac
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Any GPS needs to have a clear view. Nosecone or not, you can't have metal or carbon fiber over the antenna.
Additionally, you can buy two eggfinders and two receivers for the cost of one BRB900 and one computer-requiring receiver...
"I don't like being walked straight to my rocket, because my phone sucks"
My iPhone doesn't have issues with sun.
Area66
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A CSI bring you right to the rocket too, much more close if you are in a dense forest or a corn field. Of course you have no issues, AltosDroid don't work on iPhone. .... is that petty, you have to enter the coordinate manually in your iPhone ......oh but you have an iPhone, lol
Yep. and it works in the sun.
Area66
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Seriously my phone work in the Sun too , it's nice to have telemetry, gps positioning, the telemetrum is the best for it, the eggfinder provide gps for a low cost. But on the field to simply find a rocket a CSI is hard to beat, it's so simple to use and the build in Antena very convenient to use. Of course you need a HAM. But it's simple to get
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There is another issue between RDF and GPS. With GPS one has a pretty good idea of the distance to the last packet before going off to recover.
RDF one has to shoot a line and hopefully go in the general direction of the rocket. If it goes out of range, one has to hope they get close enough
to get another fix. The sight n' go feature with some of the Garmin handheld GPS units can help in that regard with RDF tracking. Point the Garmin in the direction of the yagi antenna and will lock a datum line to follow. With RDF make sure one has a receiver with a true signal strength meter. A UV-5RS
meter is full on or off. No relative signal strength on the indicator with that radio.
A GPS tracking system can take one right to the last packet which in some cases is where the rocket lies or close enough to pickup a new packet.
Also, with a completely disappearing rocket, one that is launched and no trace is seen of it no events or what have you, it either means total recovery
failure or the rocket is so far out, it can't be seen. RDF will get one a line hopefully, whereas one can determine from the GPS display in some systems that the deployment events have occurred in sequence or lack thereof and the GPS altitude of the decending rocket.
Another factor is time. If one lives in a area where weather is variable, seasonable and the frequency of launches sparse, would be nice to get the rocket back in a quick fashion so one can fly the next one. If one lives with year round flyable weather and an accessible launch site, the pressure to fly might not be as great. If it takes a long time to find a particular rocket, it's not a big deal to them. I'm in the former position and lost a lot of flight opportunities searching for
"lost" rockets before incorporating tracking.
For those that fly in a "featureless" expanse of land, two dots and a line is all that's needed with a GPS tracker. For those in the central part of the country with farmland, it might be helpful to "see" a tentative recovery site with respect to nearby roads and landmarks. Would help with driving close to the landing site.
There are some folks who are masters with RDF and looks to me they are so good, they can smell the direction to point the antenna.
Of course if a visual is had of the descending rocket, RDF certainly can effect recovery out of standing vegetation or corn stubble. One plus of RDF is the transmitters are small and tough. I've witnessed several flights where the rocket landed in sight, was recovered and it was discovered the tracker flew off the shockcord after the rocket was brought back. Sure enough, a signal was heard and led the user right up to the tracker lying in the field.
One comment on GPS screens, phones laptops etc. I've seen 5 handheld Garmin units from a monochrome Legend, VistaHcX to a 60CsX and one can generally
hold them at an angle to see the screen in sunlight. They're designed for that. Laptop screens, unless they are a pricey unit designed for sunlight, forget it.
Either put them in a box on a table for a sunshade or use them inside a vehicle and transfer the coordinates to a handheld GPS or phone.
Phones? If you have one you can read in the sun then great, you're lucky. If not, one can try getting a matte screen protector as that can help a little bit or get a little semi-deep cardboard box fitted to your device and spraypaint the inside with flat black paint. If one faces the sun with the device in the box, they will be better able to see the screen. I've done that with a Nexus 7 with an EggFinder receiver and can use a ham radio H/T with a B/T Mobilinkd TNC for APRS tracking when needed. Kurt
RDF one has to shoot a line and hopefully go in the general direction of the rocket. If it goes out of range, one has to hope they get close enough
to get another fix. The sight n' go feature with some of the Garmin handheld GPS units can help in that regard with RDF tracking. Point the Garmin in the direction of the yagi antenna and will lock a datum line to follow. With RDF make sure one has a receiver with a true signal strength meter. A UV-5RS
meter is full on or off. No relative signal strength on the indicator with that radio.
A GPS tracking system can take one right to the last packet which in some cases is where the rocket lies or close enough to pickup a new packet.
Also, with a completely disappearing rocket, one that is launched and no trace is seen of it no events or what have you, it either means total recovery
failure or the rocket is so far out, it can't be seen. RDF will get one a line hopefully, whereas one can determine from the GPS display in some systems that the deployment events have occurred in sequence or lack thereof and the GPS altitude of the decending rocket.
Another factor is time. If one lives in a area where weather is variable, seasonable and the frequency of launches sparse, would be nice to get the rocket back in a quick fashion so one can fly the next one. If one lives with year round flyable weather and an accessible launch site, the pressure to fly might not be as great. If it takes a long time to find a particular rocket, it's not a big deal to them. I'm in the former position and lost a lot of flight opportunities searching for
"lost" rockets before incorporating tracking.
For those that fly in a "featureless" expanse of land, two dots and a line is all that's needed with a GPS tracker. For those in the central part of the country with farmland, it might be helpful to "see" a tentative recovery site with respect to nearby roads and landmarks. Would help with driving close to the landing site.
There are some folks who are masters with RDF and looks to me they are so good, they can smell the direction to point the antenna.
Of course if a visual is had of the descending rocket, RDF certainly can effect recovery out of standing vegetation or corn stubble. One plus of RDF is the transmitters are small and tough. I've witnessed several flights where the rocket landed in sight, was recovered and it was discovered the tracker flew off the shockcord after the rocket was brought back. Sure enough, a signal was heard and led the user right up to the tracker lying in the field.One comment on GPS screens, phones laptops etc. I've seen 5 handheld Garmin units from a monochrome Legend, VistaHcX to a 60CsX and one can generally
hold them at an angle to see the screen in sunlight. They're designed for that. Laptop screens, unless they are a pricey unit designed for sunlight, forget it.
Either put them in a box on a table for a sunshade or use them inside a vehicle and transfer the coordinates to a handheld GPS or phone.
Phones? If you have one you can read in the sun then great, you're lucky. If not, one can try getting a matte screen protector as that can help a little bit or get a little semi-deep cardboard box fitted to your device and spraypaint the inside with flat black paint. If one faces the sun with the device in the box, they will be better able to see the screen. I've done that with a Nexus 7 with an EggFinder receiver and can use a ham radio H/T with a B/T Mobilinkd TNC for APRS tracking when needed. Kurt
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Unfortunately, the answer is a lot more complicated; it's not a work/won't work situation. Putting an antenna in parallel with threaded rod and near other electronics will attenuate the signal, but whether the attenuation is enough to prevent the signal from being received is a lot more complex.
Grant Saviers, the antenna guru who wrote that Antenna Basics section of my GPS Tracking page had this to say:
I simplified this and added two paragraphs to my introductory section on transmitters:
High Desert Rocketry
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Some personal reflections on easy to use tracking devices. Though this thread is about electronic devices there are some visual tracking methods that can be used: reflective mylar streamer, super bright LEDs and or reflective tape wrapped around airframe for night tracking.
Reflective mylar is really inexpensive and easy to replace if you rocket comes 'down hard'. Last year I saw a rocket go out of site (~8,000') but saw something glinting all the way down about a mile away. I walked out with the owner to see what it was, just about 3 feet of thin reflective mylar rolled up and stuffed into the tube with the small chute. It was light, durable, and could be seen flashing all the way down in the sun. Florescent colored chutes help too.
Reflective tape around the airframe. Not a choice for the daytime but if the rocket comes down on an open area, it can be spotted a long way off with a flashlight and for miles with a cheap $1 hand held red laser. Try it with a stop sign down the street at night, hit the sign with the laser and it lights up like you wouldn't believe; we used a simple mirror reflecting the sun light to locate laser reflectors miles away on the sides of mountains for a National Science Foundation seismic study. Also, it may not hold up if your're flying mach+
Super bright LEDs are cheap, small, lightweight, and last a long time when used in a blinking mode and can be seen in the open at long distances...the more you use the better chance you have that one will be pointed somewhat in your direction.
Then there are small audible trackers, I've used an inexpensive one from the dollar stores that are sold for putting on you house door that goes off when the door opens...easy to install in a rocket for locating in areas with lots of vegetation.
Now for electronics. Unless you are made of money and I'm not, I look for electronics that will do the job and not cost an arm and a leg should you lose the rocket due to a hard landing. I've used both RDF and GPS, both have advantages and some disadvantages.
RDF:
I've used them in the military and in volunteer sheriff search and rescue for downed aircraft (ELTs) and avalanche beacons to save lives. I've also used them in amateur rockets. You need to know their limitations and how to use; practice is advised before needing it to find a lost rocket.
I included an inexpensive Big Red Bee RDF at the last minute in a large hybrid project I was part of to backup the only other system, a single Big Red Bee GPS unit that had just been purchased. The RF was duct taped in the nose cone and I used a homebuilt simple 3-element yagi for tracking on the ground. After launch I listened for the beeps of the beacon as the tracking people called out altitude from the GPS telemetry. When it appeared the rocket was at or near apogee, both units stopped working, that was at 72,000' and to our northwest as I recall. That rocket is still missing. Because both stopped transmitting at about the same time, it is possible an anomalous event occurred during deployment that rendered both inoperable. On a Sugar Shot to Space launch, we had a similar BRB beacon in the nose cone. It snapped off going nearly mach 2 at almost 20,000'. The nose cone electronics freefell to the ground and the under $100 BRB beacon continued transmitting till it was recovered.
Earlier this year we flew a Real Flight Systems GPS-2 on a short flight for testing. Two main chutes were used for deployment and though the deployment charges blew out the chutes they failed to open and simply acted like streamers with the rocket coming down in a flat spin transmitting the altitude, Lat and Long coordinates. Upon impact, the GPS-2 antenna snapped off and the modem popped off and was informed it was not repairable when returned...an $800 expense that was replaced with the less expensive $500 GPS-1 unit. That needed to be purchased since it uses a proprietary ground station that becomes useless unless you buy a new Real Flight System GPS unit, a rather expensive proposition.
We tested an Eggfinder a few months ago on a 4" rocket going to ~10,000'. It was tracked on both a laptop and cell phone. Using Google Earth, it's location was plotted on a satellite image and after driving a distance of about 1.5 miles on a dirt road, we stopped, got out and walked a couple of hundred feet and found the rocket next to the bush shown on the Google Earth image. For about $100, you can't really beat that. I next plan to install it in our next near space balloon flight to 100,000' to determine if it continues working above 60,000' and what the 'in air reception distance' might be with a good ground antenna and receiver. It is far easier to improve on the ground antenna than to improve the rocket antenna.
We have used Big Red Bees for tracking some of our other balloons at 100,000' and over 50 miles distance and at extreme cold temperatures.
A few things about following the signal in RDF units. On a recent balloon flight with both a BRB GPS and a RDF beacon, both transmitted until going behind a mountain. We were about 40 miles distant as 100+ mph winds at 40,000' carried the payload on chute away from us. We had a RDF heading of ~95 degrees to the east. All that told us was somewhere along that direction...could be 10 miles or 100 miles away. The GPS told us the last location received was 38 miles away at 95 degrees to the east. We drove to the last GPS coordinates and found the balloon payload and chute in a ravine about two miles distant by following the direction where the wind would have blown the payload. It was interesting to note, neither GPS nor RDF could be heard transmitting until we were within a few hundred feet of the ravine. If we had relied exclusively on the RDF, we probably would not have found it as 20-100 miles is a long distance to be driving/walking around hoping to pick up a signal even though that balloon carried in excess of $2,000 worth of needed experimental electronic sensors.
Another 'story' is of helping a friend locate his 3" minimum diameter rocket at Black Rock. It was his first time using RDF and could not locate the rocket. We went over some basics and decided the signal was stronger to the north. We drove a couple miles in that direction and tried again, still further in that direction. We drove another mile and it now indicated 180 degrees back to the south. Did we pass it driving that last mile? We drove to the west a mile to triangulate the next direction. It indicated a direction back to the flight line. We drove back to the flight line and no other signals were detected. About two weeks later he got an email that someone had turned it in the the RSO. I'm sure others have stories of tracking their wayward rocket to people's homes.
Reflective mylar is really inexpensive and easy to replace if you rocket comes 'down hard'. Last year I saw a rocket go out of site (~8,000') but saw something glinting all the way down about a mile away. I walked out with the owner to see what it was, just about 3 feet of thin reflective mylar rolled up and stuffed into the tube with the small chute. It was light, durable, and could be seen flashing all the way down in the sun. Florescent colored chutes help too.
Reflective tape around the airframe. Not a choice for the daytime but if the rocket comes down on an open area, it can be spotted a long way off with a flashlight and for miles with a cheap $1 hand held red laser. Try it with a stop sign down the street at night, hit the sign with the laser and it lights up like you wouldn't believe; we used a simple mirror reflecting the sun light to locate laser reflectors miles away on the sides of mountains for a National Science Foundation seismic study. Also, it may not hold up if your're flying mach+
Super bright LEDs are cheap, small, lightweight, and last a long time when used in a blinking mode and can be seen in the open at long distances...the more you use the better chance you have that one will be pointed somewhat in your direction.
Then there are small audible trackers, I've used an inexpensive one from the dollar stores that are sold for putting on you house door that goes off when the door opens...easy to install in a rocket for locating in areas with lots of vegetation.
Now for electronics. Unless you are made of money and I'm not, I look for electronics that will do the job and not cost an arm and a leg should you lose the rocket due to a hard landing. I've used both RDF and GPS, both have advantages and some disadvantages.
RDF:
I've used them in the military and in volunteer sheriff search and rescue for downed aircraft (ELTs) and avalanche beacons to save lives. I've also used them in amateur rockets. You need to know their limitations and how to use; practice is advised before needing it to find a lost rocket.
I included an inexpensive Big Red Bee RDF at the last minute in a large hybrid project I was part of to backup the only other system, a single Big Red Bee GPS unit that had just been purchased. The RF was duct taped in the nose cone and I used a homebuilt simple 3-element yagi for tracking on the ground. After launch I listened for the beeps of the beacon as the tracking people called out altitude from the GPS telemetry. When it appeared the rocket was at or near apogee, both units stopped working, that was at 72,000' and to our northwest as I recall. That rocket is still missing. Because both stopped transmitting at about the same time, it is possible an anomalous event occurred during deployment that rendered both inoperable. On a Sugar Shot to Space launch, we had a similar BRB beacon in the nose cone. It snapped off going nearly mach 2 at almost 20,000'. The nose cone electronics freefell to the ground and the under $100 BRB beacon continued transmitting till it was recovered.
Earlier this year we flew a Real Flight Systems GPS-2 on a short flight for testing. Two main chutes were used for deployment and though the deployment charges blew out the chutes they failed to open and simply acted like streamers with the rocket coming down in a flat spin transmitting the altitude, Lat and Long coordinates. Upon impact, the GPS-2 antenna snapped off and the modem popped off and was informed it was not repairable when returned...an $800 expense that was replaced with the less expensive $500 GPS-1 unit. That needed to be purchased since it uses a proprietary ground station that becomes useless unless you buy a new Real Flight System GPS unit, a rather expensive proposition.
We tested an Eggfinder a few months ago on a 4" rocket going to ~10,000'. It was tracked on both a laptop and cell phone. Using Google Earth, it's location was plotted on a satellite image and after driving a distance of about 1.5 miles on a dirt road, we stopped, got out and walked a couple of hundred feet and found the rocket next to the bush shown on the Google Earth image. For about $100, you can't really beat that. I next plan to install it in our next near space balloon flight to 100,000' to determine if it continues working above 60,000' and what the 'in air reception distance' might be with a good ground antenna and receiver. It is far easier to improve on the ground antenna than to improve the rocket antenna.
We have used Big Red Bees for tracking some of our other balloons at 100,000' and over 50 miles distance and at extreme cold temperatures.
A few things about following the signal in RDF units. On a recent balloon flight with both a BRB GPS and a RDF beacon, both transmitted until going behind a mountain. We were about 40 miles distant as 100+ mph winds at 40,000' carried the payload on chute away from us. We had a RDF heading of ~95 degrees to the east. All that told us was somewhere along that direction...could be 10 miles or 100 miles away. The GPS told us the last location received was 38 miles away at 95 degrees to the east. We drove to the last GPS coordinates and found the balloon payload and chute in a ravine about two miles distant by following the direction where the wind would have blown the payload. It was interesting to note, neither GPS nor RDF could be heard transmitting until we were within a few hundred feet of the ravine. If we had relied exclusively on the RDF, we probably would not have found it as 20-100 miles is a long distance to be driving/walking around hoping to pick up a signal even though that balloon carried in excess of $2,000 worth of needed experimental electronic sensors.
Another 'story' is of helping a friend locate his 3" minimum diameter rocket at Black Rock. It was his first time using RDF and could not locate the rocket. We went over some basics and decided the signal was stronger to the north. We drove a couple miles in that direction and tried again, still further in that direction. We drove another mile and it now indicated 180 degrees back to the south. Did we pass it driving that last mile? We drove to the west a mile to triangulate the next direction. It indicated a direction back to the flight line. We drove back to the flight line and no other signals were detected. About two weeks later he got an email that someone had turned it in the the RSO. I'm sure others have stories of tracking their wayward rocket to people's homes.
dixontj93060
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High Desert Rocketry, thanks for the real-life, practical experiences; it helps us all.
(Snip for Brevity's Sake)
We tested an Eggfinder a few months ago on a 4" rocket going to ~10,000'. It was tracked on both a laptop and cell phone. Using Google Earth, it's location was plotted on a satellite image and after driving a distance of about 1.5 miles on a dirt road, we stopped, got out and walked a couple of hundred feet and found the rocket next to the bush shown on the Google Earth image. For about $100, you can't really beat that. I next plan to install it in our next near space balloon flight to 100,000' to determine if it continues working above 60,000' and what the 'in air reception distance' might be with a good ground antenna and receiver. It is far easier to improve on the ground antenna than to improve the rocket antenna.
------------------------------------------------------------------------------------------------------------------------------------------------------------------
Here's some specs on the Maestro GPS in the EggFinder:
https://www.embeddedworks.net/satl164.html
https://support.maestro-wireless.com/knowledgebase.php?article=14
The second link suggests the speed and altitude is an AND situation. If that's true, should work with a rocket at apogee and low speed above 60k'. But I don't know the reliability of the second link. You may still have to risk a balloon test to find out. It might very well be O.K. above 60k'.
Here is a link about compatible high alt GPS units but it's outdated:
https://showcase.netins.net/web/wallio/GPSrcvrsvs60kft.htm
Here's a newer link on high alt chipsets less than a year old:
https://ukhas.org.uk/guides:gps_modules
Another one that claims 164,000' limit:
https://www.gtop-tech.com/en/product/Advanced-Altitude-Restriction/Software_Services_13.html
Shoot, sorry I couldn't save you some time but remember, the purpose of the EggFinder was to inexpensively
find a rocket. Most everyday fliers don't get near 60k' and for that matter, the chipset doesn't really make a difference. Kurt
We tested an Eggfinder a few months ago on a 4" rocket going to ~10,000'. It was tracked on both a laptop and cell phone. Using Google Earth, it's location was plotted on a satellite image and after driving a distance of about 1.5 miles on a dirt road, we stopped, got out and walked a couple of hundred feet and found the rocket next to the bush shown on the Google Earth image. For about $100, you can't really beat that. I next plan to install it in our next near space balloon flight to 100,000' to determine if it continues working above 60,000' and what the 'in air reception distance' might be with a good ground antenna and receiver. It is far easier to improve on the ground antenna than to improve the rocket antenna.
------------------------------------------------------------------------------------------------------------------------------------------------------------------
Here's some specs on the Maestro GPS in the EggFinder:
https://www.embeddedworks.net/satl164.html
https://support.maestro-wireless.com/knowledgebase.php?article=14
The second link suggests the speed and altitude is an AND situation. If that's true, should work with a rocket at apogee and low speed above 60k'. But I don't know the reliability of the second link. You may still have to risk a balloon test to find out. It might very well be O.K. above 60k'.
Here is a link about compatible high alt GPS units but it's outdated:
https://showcase.netins.net/web/wallio/GPSrcvrsvs60kft.htm
Here's a newer link on high alt chipsets less than a year old:
https://ukhas.org.uk/guides:gps_modules
Another one that claims 164,000' limit:
https://www.gtop-tech.com/en/product/Advanced-Altitude-Restriction/Software_Services_13.html
Shoot, sorry I couldn't save you some time but remember, the purpose of the EggFinder was to inexpensively
find a rocket. Most everyday fliers don't get near 60k' and for that matter, the chipset doesn't really make a difference. Kurt
Last edited:
bobkrech
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The reason GPS units manufactured or sold in the US don't operate above 60 Kft and 1,000 knots has nothing to do with electronics. US ITAR regulations mandate that Civilian GPS units manufactured or sold in the US will not operate beyond these limits. Manufacturers of GPS units outside the US for use outside the US are not necessarily bound by US laws and regulations.
Bob
Bob
They are not hard to find if one desires one: https://www.argentdata.com/catalog/product_info.php?cPath=23&products_id=174
along with some of the other links I posted.
Some of the units the manufacturers do 1000knots AND 60,000' for lockout instead of OR. Meaning if drifting along at 100k' at slow speed, the unit will still report above 60k as long as the speed limit isn't reached. Problem is some makers aren't so clear as to how their device behaves. Kurt
High Desert Rocketry
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Flew the eggfinder again today to over 19,000' at a different launch site and was guided right to it after losing sight using ever clear propellant without smoke tracking. I'm sold.
Salvage-1
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+1 on the BRB900, love mine. I am now getting serious and have got myself a TeleMega, Yagi, and TeleBT.
One thing that I will point out is the you should be aware of WHAT king of GPS co-ords your tracker is giving you, and what type the map app is expecting. You may need a GPS Co-ord converter, like this one.
I have also flown my BRB900 with the aerial (standard wire one) along the same axis as, and only 1/4 inch away from, a 1/4" all-thread. Still found the rocket each time it has flown, not had a problem with receiving data packets either.
Another comment of the BRB900, and most trackers. Write down the last set of co-ords you receive, then turn the receiver off. Turn it back on again and if you still get packets, walk towards them. If at this point you don't get packets, walk towards the last co-ords you wrote down and watch for the receiver to start updating, when it does this you are close.
One thing that I will point out is the you should be aware of WHAT king of GPS co-ords your tracker is giving you, and what type the map app is expecting. You may need a GPS Co-ord converter, like this one.
I have also flown my BRB900 with the aerial (standard wire one) along the same axis as, and only 1/4 inch away from, a 1/4" all-thread. Still found the rocket each time it has flown, not had a problem with receiving data packets either.
Another comment of the BRB900, and most trackers. Write down the last set of co-ords you receive, then turn the receiver off. Turn it back on again and if you still get packets, walk towards them. If at this point you don't get packets, walk towards the last co-ords you wrote down and watch for the receiver to start updating, when it does this you are close.
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jus_rockets
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19K WOW! Did you get signal all the way up and down or when did you regain the signal? Also how far out did you land? What type of antennas did you use? I have thinking of adding a linear amplifier to increase the range but now I am thinking I won't need it at all.
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