Homebrew GPS Tracker

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ksaves2

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I hate to say it but I remember the "old days". ARTS had a GPS system that integrated into their fine deployment altimeter but if I recall correctly it was close to $1k for all the bits. I have a system downstairs I bought second hand for way less. (It has a pretty big footprint.)

Beeline GPS was something like $234.00 back in the day. One had to be a Ham radio operator (at that time) and have an APRS receiver (likely a D7A(g)) so likely pushing a little less than $1k.

Add a Garmin 60Cs or 60CsX into the mix with the D7A(g) gave real time live map tracking. That definitely pushed the cost in the $1k range. I had a BL GPS go in on a core sample rocket and losing ~$250.00 in the tracker and battery hurt not including the deployment electronics. A D72A works well now.

At a much later time, I had an incomplete chute deployment and lost an EggFinder I got at a $50.00 holiday sale. I just shrugged my shoulders and thought it's like fishing, if one wants to catch fish, they're going to lose lures. Fifty bucks was a lot easier to swallow than losing a Beeline GPS.

I will say though the GPS trackers saved many rockets that made the investment/losses worth it.

I laugh when you people gripe about getting the cheapest GPS tracker as the technology cost a heck' uva a lot more back in the day.

I did try to make a super cheap GPS tracker by using 3Dr radios like are used with drones. Problem is the radios expect two-way communication. I saw where there was supposed to be a one-way switch in the software setup but life got in the way and I never completed the project. With two way communication, if signal is lost between units, they shut down. It's advantageous to have one way communication (ie. tracker transmits no matter what whether receiver is in range or not.)

It was kind of cool as I was able to use some GPS chipsets that used the American GPS system and the Russian Glonass system for extra accuracy. I think that's the standard now. The limit of error was incredibly small. As I mentioned, I abandoned the 3Dr thing as life got in the way and I hadn't sorted out the one-way communication thing. There were also some 3Dr radios in the 70cm Ham band and I couldn't use a "cheapo" GPS chipset to get my callsign into a comment line in the NMEA sentences.

A base tracker without considering my labor was (at the time) about $35.00 for the tracker alone. I just looked and I see I tossed a system on the top of the freezer. Once my son gets done with the computer with the scanner on it, I'll post a scan of the system.

It did work mind you though the "receiver" had to be plugged into a USB port of a laptop to work with tracking software.

Kurt Savegnago a.k.a KC9LDH
 

manixFan

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DIY projects to save money is a great way to justify the accumulation of all the neat tools you have always wanted. That's capital not expense.....
OK, I can definitely get behind that part of a DIY project. I bought a couple of the Eggtimer Apogee altimeters and then had to buy a Hakko FX-888D so I could solder them together. The cost of the Hakko is an 'infrastructure' cost, completely independent of the cost of the Apogees themselves. Now I have to buy more kits and things to build to amortize the cost down to a negligible amount per project. It may take 10 years to get there, but if I can use it on 100 projects, then it only added about $1 per project.

That's my story and I'm sticking to it!


Tony
 

Dan Griffing

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Given: GPS trackers are expensive. Discussion of the prices of various models is a different thread. (Not that I wou;dn't appreciate the information, but I can look it up elsewhere.)

Suppose: I have the ability to design, assemble, and test a GPS tracker of my own. OK, I don't really, but I have the bulk of it, and let's suppose I'll successfully learn the rest.

Question: Can a functional, durable homebrew tracker be made for substantially less money than it can be purchased?
I’ve thought along similar lines in the past. What I’ve done is to use Arduino components to breadboard a GPS tracker system with the various GPS and 915 MHz modules to one of the wide variety of Arduino-compatible microprocessors available because the firmware you have to write is then all standard. (I have over a dozen years of experience as a professional firmware engineer, so trust me on the importance of this.)

First, I’ve learned is that there is a wide variation in the quality, sensitivity, and functional positions per second of the GPS modules that are available, and that’s one of the two critical areas of design. Its difficult to find on that’s sensitive to American and Russian satellites and has more than a clunky 1 position per second output.

Second, I’ve also learned that getting at least a 10 mile effective range with the 915 MHz RF technology and not interfering with the other GPS trackers out there is anything but a trivial task.

So after spending a considerable amount for Arduino modules to see what would work at least as good as the suite of Eggtimer GPS tracker that I already built for comparison, I realized how costly it would be to duplicate the development effort that’s already been done. Going the DIY route is not a money saving thing for equal or better performance.

And then I saw the specs for the Featherweight tracker system and what it could do. From the beginning I’ve been drooling over the other rocketeers who had Multitronix trackers in their nosecones with the voice of “Kate” calling out the telemetry as their rocket went four miles high and further down range. It appears that the Featherweight tracker system gives you that for a quarter of the cost and in a very compact package with no years of development hassles.

So although I’m an instrument developer at heart, I’ve boxed up my Arduino stuff because I’d rather be flying rockets instead.
 

KilroySmith

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>>> Question: Can a functional, durable homebrew tracker be made for substantially less money than it can be purchased?
Let's start with "Functional". For some set of requirements, the answer is "yes".
Here's a $11 GPS with a serial output that might hook right up to one of these $20 transmitters (Prices are probably cheaper on Alibaba or Ebay). Use another of the $20 transmitters as a receiver on the ground, hooked up to a $10 Arduino with a $10 Bluetooth board, and use your phone to interpret/display the position. So for about $75 and a number of hours of software, you can build a functional GPS tracker that will probably work for a mile. If you want a longer range, the RC and Drone community has transmitter/receiver modules with several miles of range, but the price goes up.

Now, durable is a different problem. It'll probably be difficult to hook all these together and have them work reliably launch after launch - but with some thought, skill, and hardware it's probably do-able. It's probably not reasonable to expect that the first one you bolt together will last for multiple launches, so expect to be diddling with this for awhile.

As others have said, if your time is cheap and your interest is high, it's certainly a do-able project; but IMHO by the time you get to "Functional" and "Durable", you'll likely have spent more real dollars than it would have cost to buy an off-the-shelf commercial part.
 

llobdelljr

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I get the DIY thing. I even have a background in electronics. However, I haven't figured out a good way to keep a 6L6 in it's socket at launch.

Mike,
Was that a 6L6 (metal), 6L6G, or 6L6GT? How about a 12AX7, 35W4, or 1625? When I built stuff with those tubes I also had a pet dinosaur :) I thought it was difficult then, but compared with the complexity of current technology and SMT, those days were easy. However, there was the disadvantage of not having 2 ounce GPS units for HPR.
Larry
 

jqavins

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I'll say again that I'm now leaning away from the whole thing. So anything further is by way of discussion.

RF electronics, data logging...
Who said data logging? Where was my rocket would be nice, but it's where is my rocket I really want.

"Boards can't be bought in ones"...
One can etch one's own boards in ones. How difficult? Big Clive makes it look easy, but that doesn't mean it is.
 

RocketDestroyer

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If you need some 1625 tubes I think I have 4 of them in a box in the garage. 4 of those in parallel would make a nice final amplifier.

To the OP, several years ago I made my own GPS tracker to use for my L1 flight. Never do anything the easy way. I designed the circuit (all surface mount) and produced the gerber files for the board shop, and populated them by hand. I made several iterations on the board using blue wire and spent countless hours writing code (not my strong point) but eventually realized the processor that I was using wasn't powerful enough. I got as far as bread boarding the next revision when I decided it would be a better use of my time to just buy one. I had fun and I learned a lot but I'm happy with the decision I made to stop work on the unit I was making. I made mine because I wanted to learn some new skills. I sure as heck didn't save any money building my own, far from it.

If you decide to build your own, do it for the right reasons.
 

jqavins

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Going the DIY route is not a money saving thing for equal or better performance.
Ah, but there's the thing. "Equal" is the goal in some respects. Equal in others, and better in any respect, is overkill for me. For example, "clunky 1 position per second output" is more than enough for "Hey, dummy, I'm over here!" Perhaps the vacabulary is wrong; it seems I should never have typed "tracker", but rather "locator". A quick Google search just now did not reveal any results more suited to my desires using either word than the other.
 

ksaves2

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Ah, but there's the thing. "Equal" is the goal in some respects. Equal in others, and better in any respect, is overkill for me. For example, "clunky 1 position per second output" is more than enough for "Hey, dummy, I'm over here!" Perhaps the vocabulary is wrong; it seems I should never have typed "tracker", but rather "locator". A quick Google search just now did not reveal any results more suited to my desires using either word than the other.
Cripes, The one position every 5 seconds per the Ham radio APRS protocol is enough to track and find a rocket. The once per second is overkill and in reality doesn't work so well with the entry level trackers "IF" one wants to get every last position plot for later mapping. Both systems lead to found rockets nonetheless with the 70cm/400Mhz band and the 2 meter band (144Mhz) with a better propagation in air and ground footprint. Nonetheless, the 900Mhz stuff is more than adequate for sport rockets. (Kate not withstanding as it uses a higher powered transmitter than the entry level hardware.)

I've recorded APRS data and later plotted it on a map using Ham radio software and got decent plots. With the 1/sec 900Mhz trackers I find the data is no better than the once every 5 seconds reporting with APRS as far as finding a rocket is concerned. Kate excluded. The issue might be that the 900Mhz stuff is lower power. The onboard GPS chipsets might get a bit wonky travelling at high speed and the tumbling that occurs under drogue or no-drogue descent may upset the polarity of the signal that leads to more difficult reception. Some of that can be obviated with a higher powered transmitter (hint: Kate). A 900Mhz Yagi antenna technically would be hard to aim in a rocket's direction as the beam width is narrow. On the 2 meter and 70cm/400Mhz band a Yagi can help with reception. I've found a 900Mhz Yagi helpful with ground recovery of a rocket as I generally know where to aim the Yagi once the rocket is down, based on the plot. As long as the wind isn't blowing the rocket away, the Yagi gives a quicker fix and final position than not using a Yagi. I simply remove the stock 900Mhz antenna and plug in the Yagi when the rocket is down and I know where to point the antenna as I have the last know position fix with the rocket 100 feet or so in the air.

A so called " super cheap" GPS tracker not related to cellphone towers, good luck! I got close but no cigar at one time. GPS is still the way to go to find rockets.
Ever price a Walston or Rocket Hunter RDF system back in the day? They easily cost more than the currently available GPS trackers now by eons of dollars.

Kurt Savegnago
 

Dan Griffing

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Cripes, The one position every 5 seconds per the Ham radio APRS protocol is enough to track and find a rocket. The once per second is overkill and in reality doesn't work so well with the entry level trackers "IF" one wants to get every last position plot for later mapping. Both systems lead to found rockets nonetheless with the 70cm/400Mhz band and the 2 meter band (144Mhz) with a better propagation in air and ground footprint. Nonetheless, the 900Mhz stuff is more than adequate for sport rockets. (Kate not withstanding as it uses a higher powered transmitter than the entry level hardware.)

I've recorded APRS data and later plotted it on a map using Ham radio software and got decent plots. With the 1/sec 900Mhz trackers I find the data is no better than the once every 5 seconds reporting with APRS as far as finding a rocket is concerned. Kate excluded. The issue might be that the 900Mhz stuff is lower power. The onboard GPS chipsets might get a bit wonky travelling at high speed and the tumbling that occurs under drogue or no-drogue descent may upset the polarity of the signal that leads to more difficult reception. Some of that can be obviated with a higher powered transmitter (hint: Kate). A 900Mhz Yagi antenna technically would be hard to aim in a rocket's direction as the beam width is narrow. On the 2 meter and 70cm/400Mhz band a Yagi can help with reception. I've found a 900Mhz Yagi helpful with ground recovery of a rocket as I generally know where to aim the Yagi once the rocket is down, based on the plot. As long as the wind isn't blowing the rocket away, the Yagi gives a quicker fix and final position than not using a Yagi. I simply remove the stock 900Mhz antenna and plug in the Yagi when the rocket is down and I know where to point the antenna as I have the last know position fix with the rocket 100 feet or so in the air.

A so called " super cheap" GPS tracker not related to cellphone towers, good luck! I got close but no cigar at one time. GPS is still the way to go to find rockets.
Ever price a Walston or Rocket Hunter RDF system back in the day? They easily cost more than the currently available GPS trackers now by eons of dollars.

Kurt Savegnago
Cripes, The one position every 5 seconds per the Ham radio APRS protocol is enough to track and find a rocket. The once per second is overkill and in reality doesn't work so well with the entry level trackers "IF" one wants to get every last position plot for later mapping. Both systems lead to found rockets nonetheless with the 70cm/400Mhz band and the 2 meter band (144Mhz) with a better propagation in air and ground footprint. Nonetheless, the 900Mhz stuff is more than adequate for sport rockets. (Kate not withstanding as it uses a higher powered transmitter than the entry level hardware.)

I've recorded APRS data and later plotted it on a map using Ham radio software and got decent plots. With the 1/sec 900Mhz trackers I find the data is no better than the once every 5 seconds reporting with APRS as far as finding a rocket is concerned. Kate excluded. The issue might be that the 900Mhz stuff is lower power. The onboard GPS chipsets might get a bit wonky travelling at high speed and the tumbling that occurs under drogue or no-drogue descent may upset the polarity of the signal that leads to more difficult reception. Some of that can be obviated with a higher powered transmitter (hint: Kate). A 900Mhz Yagi antenna technically would be hard to aim in a rocket's direction as the beam width is narrow. On the 2 meter and 70cm/400Mhz band a Yagi can help with reception. I've found a 900Mhz Yagi helpful with ground recovery of a rocket as I generally know where to aim the Yagi once the rocket is down, based on the plot. As long as the wind isn't blowing the rocket away, the Yagi gives a quicker fix and final position than not using a Yagi. I simply remove the stock 900Mhz antenna and plug in the Yagi when the rocket is down and I know where to point the antenna as I have the last know position fix with the rocket 100 feet or so in the air.

A so called " super cheap" GPS tracker not related to cellphone towers, good luck! I got close but no cigar at one time. GPS is still the way to go to find rockets.
Ever price a Walston or Rocket Hunter RDF system back in the day? They easily cost more than the currently available GPS trackers now by eons of dollars.

Kurt Savegnago
Having 1 GPS read-out every 5 seconds might be sufficient under normal recovery situations but when your bird has a ballistic arc at over 100 mph from gravity turn or weather-vaning it really helps to have a GPS module that won’t loose satellite position lock to track your bird as it zooms downrange.

In April I had an unfortunate “lawn dart” situation from parachutes that didn’t deploy but my nosecone mounted Feathweight GPS performed its last service by generating high speed location transmissions until just before impact. The Feathweight iPhone app led me directly to the crash sight, which a 1 location every 5 seconds could never have done.

If the issue is spending hundreds of dollars to develop a DIY GPS rocket finder system with a “clunky” GPS in it versus spending a similar amount on a complete high performance one, unless you’re rewarding yourself points for rolling your own, the choice seems to be obvious.
 
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Michael L

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[QUOTE="llobdelljr, post: 2147678, member: 1721"
Mike,
Was that a 6L6 (metal), 6L6G, or 6L6GT? How about a 12AX7, 35W4, or 1625? When I built stuff with those tubes I also had a pet dinosaur :) I thought it was difficult then, but compared with the complexity of current technology and SMT, those days were easy. However, there was the disadvantage of not having 2 ounce GPS units for HPR.
Larry
[/QUOTE]
All of the above. I love tubes, restoring old tube radios and test equipment, and building a guitar amp every now and then.
 
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Michael L

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One can etch one's own boards in ones. How difficult? Big Clive makes it look easy, but that doesn't mean it is.
That's a very good point. Paul Carlson (Mr. Carlson's Lab) also has a good tutorial on how to do it. I've done it. I've made them with my circuit board mill too.
 

RocketScientistAustralia

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There are many acceptable reasonably priced commercial trackers available. There’s no need to reinvent the wheel.
However some people might require something different. At that point you might want to consider building one for your purposes.
A tracker has generally 3 things.
A GPS receiver:- what signals do you want / need to receive. Galileo, Baidu, GNSS, starlink??
what receiving antenna will you use? Flat chip? Only looks away from flat side. Designed to get a signal looking flat through a car window and not ideal in a spinning rocket.
Helical antenna. Good omnidirectional receiving but weaker signal.
Something else.
A method to record locally, gps location into memory:- lots of choices there. TF cards, Arduino etc.
And finally a radio link to talk back to whatever you’re using as a ground station :-900 MHz. 433 415 etc. licence or no licence, transmitter and receiver pair or 2 transceivers. Single antenna or diversity antenna?
There are a whole heap of choices that you might want to make for your specific project.

So what do I use. 2x Telemetrum2 for dual redundancy dual deployment
and Ublox5 with helical antenna connected to a RFDesign 1 watt diversity antennas transceiver as a GPS Link. Simply connected to the UBlox software set in record mode on a laptop.
The Ublox with the Helical antenna gives me the best GPS performance in a real world dynamic rocket environment. There are newer versions.
The Telemetrums are approved for record attempts.

What you might want/ do, depends on you
 

Dan Griffing

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That's a very good point. Paul Carlson (Mr. Carlson's Lab) also has a good tutorial on how to do it. I've done it. I've made them with my circuit board mill too.
For someone who wants to do their own boards I’d recommend KiCad as a complete, quality open source package. Its the European toolset that’s the official board deployment tool used by the scientists at CERN. Most board developers in the US used Altium, but it’s expensive. Surprisingly, KiCad has some quite advanced auto tracing layout features that Altium doesn’t have.

The circuit layout is also constrained by board design rules that board etching companies will tell you are necessary so that the board you have them make will actually work. It does get pretty complicated even if you are an electrical engineer.
 

Michael L

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For someone who wants to do their own boards I’d recommend KiCad as a complete, quality open source package. Its the European toolset that’s the official board deployment tool used by the scientists at CERN. Most board developers in the US used Altium, but it’s expensive. Surprisingly, KiCad has some quite advanced auto tracing layout features that Altium doesn’t have.

The circuit layout is also constrained by board design rules that board etching companies will tell you are necessary so that the board you have them make will actually work. It does get pretty complicated even if you are an electrical engineer.
I've been using Eagle since it was called Cadsoft Eagle (decades?), now it's called Autodesk Eagle. It and Fusion 360 work together though I'm no wiz at Fusion 360. When Cadsoft announced that Autodesk had bought Eagle a lot of people, including me, tried KiCad. The transition was too frustrating for my liking. Nothing against KiCad, I just preferred familiar territory. Autodesk, of course, had to change some things but it's still useable.
 

ksaves2

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There are many acceptable reasonably priced commercial trackers available. There’s no need to reinvent the wheel.
However some people might require something different. At that point you might want to consider building one for your purposes.
A tracker has generally 3 things.
A GPS receiver:- what signals do you want / need to receive. Galileo, Baidu, GNSS, starlink??
what receiving antenna will you use? Flat chip? Only looks away from flat side. Designed to get a signal looking flat through a car window and not ideal in a spinning rocket.
Helical antenna. Good omnidirectional receiving but weaker signal.
Something else.
A method to record locally, gps location into memory:- lots of choices there. TF cards, Arduino etc.
And finally a radio link to talk back to whatever you’re using as a ground station :-900 MHz. 433 415 etc. licence or no licence, transmitter and receiver pair or 2 transceivers. Single antenna or diversity antenna?
There are a whole heap of choices that you might want to make for your specific project.

So what do I use. 2x Telemetrum2 for dual redundancy dual deployment
and Ublox5 with helical antenna connected to a RFDesign 1 watt diversity antennas transceiver as a GPS Link. Simply connected to the UBlox software set in record mode on a laptop.
The Ublox with the Helical antenna gives me the best GPS performance in a real world dynamic rocket environment. There are newer versions.
The Telemetrums are approved for record attempts.

What you might want/ do, depends on you
Yup, All of what you say is totally correct. Helical antennas are better along with a GPS chipset that has an onboard amplifier. The dynamics of rocket flight means one is not likely going to get 100% data recovery but once under drogue or main chute, enough positions will stream in to have a successful recovery.

I had a core sample and there was one received position. It was when the rocket was 75 feet up and that one position was all it took to get to the rocket. It was spiral wound fiberglass so a new nosecone and the rocket still flies.

Kurt
(Grease got in the engine charge hole so the 4F didn’t go off.)
 

yo3ict

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Coming from the field of high-altitude ballooning, there is a number of us that develop and fly homebrew GPS tracking systems. Provided you got an amateur radio license, one of such systems can be build for about 30$. It yields up to 30 hours of runtime on a single AAA cell (first pic).

If you want to go more advanced, I'll be flying my own flight computer that is based on a single-board Pi Zero computer and a daughter board that has the GPS and LoRa components. Add a baro/IMU like I did, boost the LoRa downlink rate to 10kbps, on-board data storage at about 100Hz and that's it. Firmware is a custom PITS - Pi in the sky : https://github.com/PiInTheSky/pits/ This exact hardware already flew on two high-altitude missions, hence the less-than-optimal orientation of the GPS antenna. It is what it is.
 

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The specific antenna and how it’s integrated will have the biggest impact on performance. Not sure I’d agree that helical is “better” for rocketry. Everything is a trade off.
 

ksaves2

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I had a Ublox 5 chipset with an allegedly amplified Sarantel helical antenna. I would get a lock in my basement after a short period of time. If I would have known the technology would go away, I would have bought three of them instead of one. They were pricey at $128.00. I imagine they would have performed well in rocketry given the velocity restraints and paired with a 50 to 100mW transmitter in the 70cm band would have been I think impressive.
I was working with it and dropped it. End of story and weren't available anymore. Kurt
 

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I've never had any problems with the integrated patch antenna in the Ublox SAM-M8Q.
 

rokit

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Time is money . . . but don't forget factors on the other side of the equation, such as the value of any knowledge and/or skills gained, enjoyment of said time spent, and sense of fulfillment when success is achieved -- just to name a few.
 

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Yup, All of what you say is totally correct. Helical antennas are better along with a GPS chipset that has an onboard amplifier. The dynamics of rocket flight means one is not likely going to get 100% data recovery but once under drogue or main chute, enough positions will stream in to have a successful recovery.

I had a core sample and there was one received position. It was when the rocket was 75 feet up and that one position was all it took to get to the rocket. It was spiral wound fiberglass so a new nosecone and the rocket still flies.

Kurt
(Grease got in the engine charge hole so the 4F didn’t go off.)
I had a Ublox 5 chipset with an allegedly amplified Sarantel helical antenna. I would get a lock in my basement after a short period of time. If I would have known the technology would go away, I would have bought three of them instead of one. They were pricey at $128.00. I imagine they would have performed well in rocketry given the velocity restraints and paired with a 50 to 100mW transmitter in the 70cm band would have been I think impressive.
I was working with it and dropped it. End of story and weren't available anymore. Kurt
Wowsers. That took longer to find than I'd anticipated..... https://www.gnss.store/gnss-gps-mod...s-receiver-board-with-sma-for-uav-robots.html Still available but slightly different and certainly more expensive.... I seem to remember that after the Ublox5 was released, although the chipsets became more sensitive and you could pick up GNSS satelites that the dynamic performance became legally reduced to prevent use in guided things that hurt people.
 

RocketScientistAustralia

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I've never had any problems with the integrated patch antenna in the Ublox SAM-M8Q.
The issue I perceive with the patch chip antenna on a flat board mounted vertically is that rockets spin, generally. Usually to help keep them straight in flight. So if you stand and hold your arms out you get the reception pattern of a chip antenna. That is everything in front of you and most of the front sides. Half of the sky....... Now if you start spinning all those satellites are going to go hello/ goodby depending on your rate of spin. Not all, but a good portion. So depending on what your acquisition lock time is and your rate of spin, you may not lock onto the satellite. At least not for long.
With an antenna that has the best omnidirectional reception, the helical antenna, you give yourself the best chance of the best reception and maintaining a gps lock. All other things being equal.
Unless you have an unlocked GPS you'll still lose lock due to your chipset and legal limits, velocity, G's and altitude limits. As Kurt pointed out, sometimes you just need ONE set of co-ordinates to be transmitted. The helical antenna give you the best chance of getting one.

I'm surprised the Tracker Manufacturers haven't tested it. Or at lease made it available as an option.
 
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jqavins

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Time is money . . .
Why? How? I challenge anyone to provide a justification for that statement which surpasses the below.

Length (m, ft, lightyears, whatever) isn't money ($, €, £, whatever). Mass (kg, lbm, Daltons, whatever) isn't money. Why should time (s, whatever.) be money?

Of course the saying is figurative. I guess it refers to the money one could acquire if one were to spend 24 hours a day chasing it. And so one is expected to compare the value of whatever else one gains by using time not spent chasing money (e.g. eating, sleeping, gazing at a sunset, watching the boob tube) to the money one might have acquired in the same period.

But then one could just as well say "Time is sleep", because all the time I spend on other things (eating, gazing at sunsets, chasing money, etc.) could have been spent taking a nap. Or time is nookie. And so on.

So why should money, and the assumption that all available time will be spent chasing it, be the standard against which the value of time is measured? That seems like a really pathetic way to live. I'd rather be taking a nap.
 

manixFan

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Why? How? I challenge anyone to provide a justification for that statement which surpasses the below.

Length (m, ft, lightyears, whatever) isn't money ($, €, £, whatever). Mass (kg, lbm, Daltons, whatever) isn't money. Why should time (s, whatever.) be money?

Of course the saying is figurative. I guess it refers to the money one could acquire if one were to spend 24 hours a day chasing it. And so one is expected to compare the value of whatever else one gains by using time not spent chasing money (e.g. eating, sleeping, gazing at a sunset, watching the boob tube) to the money one might have acquired in the same period.

But then one could just as well say "Time is sleep", because all the time I spend on other things (eating, gazing at sunsets, chasing money, etc.) could have been spent taking a nap. Or time is nookie. And so on.

So why should money, and the assumption that all available time will be spent chasing it, be the standard against which the value of time is measured? That seems like a really pathetic way to live. I'd rather be taking a nap.
Easy, you are trading your time to save money, simple as that. You can spend 5 minutes ordering a tracking system that is complete and ready to go for about $400, or one that requires an hour or three of your time for about $200, or you can try and build one yourself for even less money but potentially far more time. There is a direct correlation between how much money you spend vs. how much time you spend.

So you are chasing money - you said you were a cheapskate and a goal of DIY was to save money. You can only save your money by spending your time on coming up with a DIY tracker, and you said only if it saved you a minimum threshold. It seems to me you have set a specific value on what your time is worth, so Time = Money.


Tony
 
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