TWO VERSIONS Live Tracking with APRS

HAB Guide

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Using APRS for Live Tracking and Recovery

With APRS, the Automatic Packet Reporting System, you can continuously send out information about your payload over HAM radio signals. A HAM radio Technician license is required, but it is not very difficult to study for and pass on your first try. With APRS, your payload will send a stream of basic information on a specific frequency, which is monitored by thousands of stations across the country (and around the world, on other frequencies). Some of these antennas are connected to the Internet where the data is collected and displayed on websites like aprs.fi. Some other recommended web resources for APRS are available on the Byonics website.[1]


Byonics.com is the recommended place to get APRS beacons like the MT-AIO (Micro-Trak All-in-One) HA, MT-1000, and MT-2000. Another chapter again could be written on this, and probably will be.


Explaining APRS — Automated Packet Reporting System

In the United States, on the HAM radio frequency 144.39 MHz, it is possible to transmit basic telemetry and related data to a huge network of ground stations. From these ground stations, it is possible to get updates on your payload from popular websites like aprs.fi.


In order to use an APRS system you will need at least a Technician amateur radio (HAM) license[2] from the FCC.


It is also interesting to note that because of ITAR restrictions, you will need to be careful about the GPS receiver you use. In order not to be classified as a munition, a GPS receiver must not operate when it is at or above 18 km (60,000 ft.) altitude and 515 m/s (1,200 mph) speed. Thanks to the SparkFun high altitude balloon tutorial[3] for pointing this out so clearly by way of the Wikipedia page on GPS.


Comparing Byonics APRS Systems

There are some other APRS manufacturers and systems out there but the ones from Byonics[73] are perfect for intermediate projects.


GPS and ITAR

If you’re not careful, there is an interesting situation you may find yourself in when using a GPS receiver, but it can be avoided if you know what to look for. The interesting situation is known as ITAR, the International Traffic in Arms Regulations, which exist to prevent the export of any goods that can be used in military technologies. This applies to GPS receivers because they could conceivably be used to guide missiles, drones, or any of a number of other things that the United States does not want to make exceptionally easy for other countries (or you) to do.


The regulations state that GPS receivers cannot operate when above 60,000 ft altitude when they are also traveling over 1,200 mph. This can be an issue for your balloon because manufacturers of GPS receivers usually decide to make things simple by directing their devices to simply stop working when they are above 60,000 ft, regardless of their speed. For this reason, you need to make sure that you order a “high altitude” GPS receiver that has been manufactured to only stop working if both of the ITAR-limited conditions are true.


All Other GPS & Tracking Options

If you are still looking for more radio adventures you can take a further look at the Byonics website because they are all about “Electronic Projects for Amateur Radio.” There are also very interesting projects to get into with Pi in the Sky (for Raspberry Pi), HabDuino (for Arduino), and ArgentData (like the Tracker3). In just a few more steps of complexity you will be using ArduPilot to build tracking antennas[5] and studying antenna theory.[6] Satellite communication modules are also available to purchase and use as a custom worldwide telemetry channel.


Advanced Options with Byonics Systems


The Harder, Custom Way

The TinyTrak4[7] is a Terminal Node Controller (TNC) so you will need to add power, GPS, antenna, and a transceiver to get it working. This is a bit more complicated and heavier than the usual HAB project but it has been used many times in this way. The advantage is that you can more easily transmit additional information in your packets from analog or digital inputs. However, once you have reached this level of complexity, it might make sense to consider something like an Arduino to act as a flight computer and then have that information sent out on APRS using the method described next.


The Simpler, Streamlined Way

If you have a custom set of sensor data you want to send out you can use the TinyTrak4, but at that point it might make more sense to repurpose a TinyTrak3[8] (included in the MT-1000[9] and MT-2000[10]) using a firmware replacement from Byonics (called TinyPack[11]). With this alternative firmware, it is possible to send any text-based telemetry you want to the TinyTrak3 and it will be transmitted out on APRS.


Expanded APRS Capability with ArgentData Tracker3

A UCSD launch web page[12] touches on using the ArgentData Tracker3[13] APRS system tracker. The Tracker3 provides the five standard pieces of telemetry that are often reported over APRS as well as has three additional channels (in italics):


This is a nice capability, but not unique to the Tracker3, since the same and more can be done with Byonics’ TinyTrak3 with TinyPack firmware.


ArduPilot Mega for Balloon Avionics and Tracking

The HighAltBalloon[14] page on avionics has some good documentation on using the ArduPilot Mega[15] for their system. You can also use Ardupilot to command a directional antenna toward your payload.


Single Board Computers as an Avionics Platform

If you are using a Raspberry Pi, you can purchase a Pi In The Sky.[16] For Arduino, there is HabDuino[17] from the same team. Using these types of single-board controllers/computeres is a great way to take care of various aspects of flying a high altitude balloon mission.


Space-Oriented Operating System

If you really want to get fancy you can use the open-source KubOS Flight System[18] for your mission. This is uncharted territory for me, but I’m confident that you will accomplish great things if you go this route. Let me know!


Further System Considerations from L. Paul Verhage

It is hardly a surprise that L. Paul Verhage, in his online book Near Space with the BASIC Stamp,[19] ,[20] has some good input on this topic as well. The single most interesting point of the three chapters is in Chapter 2 where he makes a distinction between the three types of avionics:



More details about avionics systems is available in the following chapters of his book:



Tracking and APRS Systems to Avoid

Some items[24] that are either no longer produced or not advised:



#FF0000

Version Two Below


Caution Against Using Cell Phones as Trackers

Using a cell phone is a popular but *completely illegal* way to track your balloon! I would also expect that using a cell phone is unreliable in many places and that’s not something I want to take a chance with. See below for the text directly from Title 47 of the eCFR[29], annotated for clarity.


Subpart H—Cellular Radiotelephone Service

§22.925 Prohibition on airborne operation of cellular telephones.

Cellular telephones installed in or carried aboard airplanes, balloons or any other type of aircraft must not be operated while such aircraft are airborne (not touching the ground). When any aircraft leaves the ground, all cellular telephones on board that aircraft must be turned off.


+----------------+-----------------+-----------------+-----------------+
| Short Name     | MT-AIO HA       | MT-1000 HAB     | MT-2000 (or     |
|                |                 |                 | MT2K)           |
+================+=================+=================+=================+
| Full Name      | Micro-Trak All- | Micro-Trak 1000 | Micro-Trak 2000 |
|                | in-One High     | High Alti- tude | (or MT-2000)    |
|                | Altitude        | Balloon Combo   |                 |
+----------------+-----------------+-----------------+-----------------+
| Design Drivers | High Power      | Lost Cost       | Mid Power       |
|                |                 |                 |                 |
|                | Long Duration   | Low Weight      | Airborne        |
|                |                 |                 | Operation       |
|                | Terrestrial     |                 |                 |
|                | Operation       | LOS/Ballooning  | LOS/Ballooning  |
|                |                 |                 |                 |
+----------------+-----------------+-----------------+-----------------+
| Cost (Without  | Total: \$220    | Total: \$320    | Total: Approx.  |
| Power)         |                 |                 | \$200           |
|                | Includes        | Includes        |                 |
|                | everything      | everything      | MT-2000: \$99   |
|                | except          | except          | w/o GPS or      |
|                | configuration   | configuration   | antenna         |
|                | cable, which is | cable, which is |                 |
|                | optional        | optional        | GPS: \$79       |
|                | because it is   | because it is   | GPS5HA (see     |
|                | preconfigured   | preconfigured   | User Guide for  |
|                |                 |                 | other options)  |
|                |                 |                 |                 |
|                |                 |                 | Antenna:  $19   |
|                |                 |                 | for V2 or V4    |
|                |                 |                 | with unity gain |
|                |                 |                 | or  $40 for the |
|                |                 |                 | V6 with 6 dB    |
|                |                 |                 | gain.           |
+----------------+-----------------+-----------------+-----------------+
| Weight         | Total: 17.9 oz. | Total: 5.3 oz.  | 0.9 oz. with    |
|                |                 |                 | SMA and DB-9    |
|                | MT-AIO: 13.7    | MT-1000: 3.7    | connectors      |
|                | oz. empty       | oz. empty       | (excludes       |
|                |                 |                 | power, GPS)     |
|                | Lithium AA:     | Lithium AA:     |                 |
|                | 0.53 oz. each   | 0.53 oz. each   |                 |
+----------------+-----------------+-----------------+-----------------+
| Size           | 6.37′′ x 2.62′′ | 2.7′′ x 1.9′′   | 1′′x 4.125′′    |
|                | x 2.06′′ case   | overall 2.2′′ x | overall 1′′ x   |
|                |                 | 1.9′′ board     | 3.1′′ board     |
|                |                 | only            | only            |
+----------------+-----------------+-----------------+-----------------+
| Current        | 35 mA with GPS  | 30 mA with GPS  |                 |
|                | 1.7Aon transmit | 700 mA on       |                 |
|                |                 | transmit        |                 |
+----------------+-----------------+-----------------+-----------------+
| Frequency      | 144-148 MHz     |                 |                 |
+----------------+-----------------+-----------------+-----------------+
| Power Output   | Adjustable, 10  | Nominal: 1.7 W  | ≥ 2 W at 9 VDC  |
|                | W Max           |                 |                 |
|                |                 | Operational: ≥  |                 |
|                |                 | 1 W throughout  |                 |
|                |                 | flight on       |                 |
|                |                 | battery power   |                 |
|                |                 |                 |                 |
|                |                 | Maximum: 2 W    |                 |
|                |                 | with 5 VDC      |                 |
+----------------+-----------------+-----------------+-----------------+
| Battery Type   | 8 Energizer     | 3 Energizer     | N/A as built    |
|                | Ultimate        | Ultimate        | but can use 6-  |
|                | Lithium AA      | Lithium AA      | or 8-battery    |
|                | (only!)         | (only!)         | pack with       |
|                |                 |                 | Energizer       |
|                |                 |                 | Ultimate        |
|                |                 |                 | Lithium         |
+----------------+-----------------+-----------------+-----------------+
| Battery        | 24 Hours @ 100% | ≤ 3 days with   | N/A             |
| Endurance      | power and       | 2-minute        |                 |
|                | 2-minute        | intervals       |                 |
|                | intervals       |                 |                 |
+----------------+-----------------+-----------------+-----------------+
| External Power | Intended for    | Nominal: 5 VDC  | Nominal: 9 VDC  |
|                | battery use but |                 |                 |
|                | can use 9-13.6  | Spec: 4.5-5.0   | Rec: 7.5-15 VDC |
|                | VDC             | VDC             |                 |
|                |                 |                 | Spec: 7.2-24    |
|                |                 | Max: 5.2 VDC    | VDC             |
+----------------+-----------------+-----------------+-----------------+
| Adjustments    | Many (path,     | Only through    | Only through    |
|                | power,          | config. cable   | config. cable   |
|                | deviation,      |                 |                 |
|                | etc.)           |                 |                 |
+----------------+-----------------+-----------------+-----------------+
| Case           | Pelican® Case   | Rigid Plastic   | "Toothpaste     |
|                |                 |                 | Tube"           |
+----------------+-----------------+-----------------+-----------------+
| High-Altitude  | Yes             | Yes             | Compatible but  |
| GPS            |                 |                 | not included.   |
|                |                 |                 | Select GPS5HA   |
|                |                 |                 | or see User     |
|                |                 |                 | Guide.          |
+----------------+-----------------+-----------------+-----------------+
| Temp. Sensor   | Yes, Analog     | Yes, Digital    | No              |
+----------------+-----------------+-----------------+-----------------+
| Report Temp. & | Yes, built-in   | Yes, built-in   | Possible with   |
| Voltage        |                 |                 | modification    |
+----------------+-----------------+-----------------+-----------------+
| Resources      | Product Page    | Product Page    | Product Page    |
|                |                 |                 |                 |
|                | User Guide      | User Guide      | User Guide      |
+----------------+-----------------+-----------------+-----------------+
Table 2 APRS System Comparison

Footnotes

[1]: 70 http://www.byonics.com/tinytrak/links.php [2]: 71 http://www.arrl.org/getting-your-technician-license [3]: 72 https://www.sparkfun.com/tutorials/361 [4]: 73 https://www.byonics.com/ [5]: 74 http://ardupilot.org/antennatracker/index.html [6]: 75 https://community.balloonchallenge.org/t/build-your-own-tracker-antenna-theory/666 [7]: 76 https://www.byonics.com/tinytrak4/ [8]: 77 https://www.byonics.com/tinytrak/ [9]: 78 https://www.byonics.com/mt-1000 [10]: 79 https://www.byonics.com/mt-2000 [11]: 80 https://www.byonics.com/tinypack/ [12]: 81 https://sites.google.com/site/ucsdnearspaceballoon/previous-launches/january-15-2011-zp [13]: 82 https://www.argentdata.com/catalog/index.php?cPath=22 [14]: 83 http://www.highaltballoon.com/avionics [15]: 84 http://ardupilot.org/antennatracker/index.html [16]: 85 http://www.pi-in-the-sky.com/ [17]: 86 http://www.habduino.org/ [18]: 87 http://www.kubos.com/ [19]: 88 http://nearsys.com/pubs/book/index.htm [20]: 89 https://sites.google.com/site/acalanesnearspaceproject/the-book-1 [21]: 90 http://nearsys.com/pubs/book/chap2.pdf [22]: 91 http://nearsys.com/pubs/book/chap3.pdf [23]: 92 http://nearsys.com/pubs/book/chap4.pdf [24]: 93 https://sites.google.com/site/ucsdnearspaceballoon/previous-launches/december-5-2009 [25]: 94 http://www.highaltitudescience.com/products/aprs-radio-transmitter [26]: 95 http://www.highaltitudescience.com/products/eagle-flight-computer [27]: 96 http://www.stratostar.net/ [28]: 97 http://www.vernier.com/products/interfaces/labq2/ [29]: 98 http://www.highaltitudescience.com/pages/federal-communications-commission-22-925 points to the e-CFR that says this is illegal, which is 22.295 at http://www.ecfr.gov/cgi-bin/text-idx?SID=3a6f5c68673c71cf564f7db91144bafe&mc=true&node=pt47.2.22&rgn=div5#se47.2.22_1925.
Copyright 2013–2021 Bryan Costanza #kj6.dev#