Member III
APRS... Anal Probe Restraint System... 
no... NO.... that's not right.
Automatic Packet Reporting System. (If this is a duplicate of something already posted please advise and I will remove.)
You're probably saying what is a Packet and what does this have to do with Overlanding? Hang with me for a minute..
A Packet is data and in the case of APRS it is speed, direction, altitude, location, and a message which typically states what frequency you are monitoring. This packet is transmitted via a 2 meter ham radio on 144.39 MHz (North America), so you have to be a licensed amateur radio operator to use APRS.
Your data packet is transmitted from your 2m radio and can be received and decoded directly by another APRS user or it can be picked up by a digital repeater (digipeater or digi) and rebroadcast. If another digi is within range of the first one it will also rebroadcast your packet. Two hops is the generally accepted standard setting. If you have a full featured APRS set up (as opposed to just a simple/dumb tracker) you can view the other stations packet info and see them on a map.
A digipeater may also be an Internet Gateway (Igate) or the Igate may be stand alone, which then copies your packet info to the net for sites such as APRS.fi and APRSdirect.com. These sites map you and your packets. This allows for your friends and family to see where you are on your adventures.
APRS can be used for more than just tracking. You can send messages to other APRS users (as long as they have a full featured APRS set up), you can send text messages, and short emails (both text and emails require that you be within range of an IGate). See this thread for more info on APRS SMS Text and Emails: OB Approved - SMS Text and Email via APRS
The APRS system also allows you to see who is around you, their distance from you, and their direction from you.... as the system was designed for situational awareness.
In addition to tracking and sending messages to check in while on your adventures, this type of system would be good for a trail run event where you could see what trail each group was on and where on the trail they were. It would also be good if you were in search and rescue. Others could see where you had been and if every S&R group had an APRS beacon you could see where everyone had been and make sure the area had been covered accordingly.
The International Space Station has an APRS digipeater on board as well and there are a couple of satellites flying around that are also APRS capable digipeaters. For more info check out this thread: APRS via Satellite
Hardware... what do you need for an APRS set up?
You could take the easy way out and just download an APRS app for your phone (remember you have to be a licensed ham to use this) however this requires that you have a cell signal. If you want to go the RF route here is what you will need.
First off you will need a radio, a radio that operates on the 2m band specifically. There are some dual band radios that allow you to run APRS on one side and voice on the other, but most do not. Most dual band radios are dual receive but single transmit which means you can transmit APRS or voice but not both at the same time though you can listen to both simultaneously. A dedicated single band (2m) radio would work great, either mobile or HT. The mobile would have more watts (and likely a better receiver) which would come in handy for areas with sparse digipeater coverage. The radios that do APRS and voice at the same time also typically have the APRS hardware built in, these radios include the Kenwood TM-D710G (mobile), Yaesu FTM-400XDR (mobile), Kenwood TH-D72A/TH-D74A (HT) and Yaesu FT2DR (HT). The mobiles are quite popular.
You will may also need a TNC or Terminal Node Controller. This device takes the digital info from the GPS and converts it into audio tones to be transmitted by the radio and vise versa. Common TNCs are the Byonics Tiny Trak, Argent Data Open Tracker, TNC-PI (Raspberry PI) and Mobilinkd. The TNC takes the digital information and converts it to audio tones to be sent out over RF. If using a smart phone with an APRS app you can connect the phone direction to the radio and the app will do the audio processing, this using the VOX (Voice activated transmit) to transmit the signal where the TNC will actually key the radio like pushing the PTT on a mic. Some of the TNCs require a GPS puck to obtain the data while others such as the Mobilinkd use the phone for the GPS data.
You may also need a display, some TNCs allow displays some don't. I prefer to have a display to see where others are and send messages, the ones that don't have a display are sometimes referred to as a dumb tracker as you can't really do anything else with it except track your vehicle.
The TNC you get may dictate the display you have to have. Some use old nav units such as the Nuvi350 while others can use small computer displays and others can use tablets/smart phones. I run the Mobilinkd and I like it because it bluetooths to the screen so it is housed in the back of the vehicle by the radio and there is no extra cord to run through the cabin of the vehicle.
There are also standalone units with the radio (10w or less), antenna and TNC in one compact unit such as the Byonics Microtrak series.
APRS is by no means the end all solution to tracking and messaging while off grid, but it's another tool to have at your disposal. APRS largely depends on hams to set up the digipeaters/igates and unfortunately there are still areas with no coverage. APRS still works simplex (radio to radio) regardless of any local APRS infastructure so if running around an area with a group you could possibly still use APRS within the group depending on terrain.
Here is an example of APRS from South Texas to Alaska.
This isn't an all inclusive write up but just something to give you an idea of what you might need to begin your own research to get set up using APRS. I and others would be glad to help if you have any questions.
no... NO.... that's not right.Automatic Packet Reporting System. (If this is a duplicate of something already posted please advise and I will remove.)
You're probably saying what is a Packet and what does this have to do with Overlanding? Hang with me for a minute..
A Packet is data and in the case of APRS it is speed, direction, altitude, location, and a message which typically states what frequency you are monitoring. This packet is transmitted via a 2 meter ham radio on 144.39 MHz (North America), so you have to be a licensed amateur radio operator to use APRS.
Your data packet is transmitted from your 2m radio and can be received and decoded directly by another APRS user or it can be picked up by a digital repeater (digipeater or digi) and rebroadcast. If another digi is within range of the first one it will also rebroadcast your packet. Two hops is the generally accepted standard setting. If you have a full featured APRS set up (as opposed to just a simple/dumb tracker) you can view the other stations packet info and see them on a map.
A digipeater may also be an Internet Gateway (Igate) or the Igate may be stand alone, which then copies your packet info to the net for sites such as APRS.fi and APRSdirect.com. These sites map you and your packets. This allows for your friends and family to see where you are on your adventures.
APRS can be used for more than just tracking. You can send messages to other APRS users (as long as they have a full featured APRS set up), you can send text messages, and short emails (both text and emails require that you be within range of an IGate). See this thread for more info on APRS SMS Text and Emails: OB Approved - SMS Text and Email via APRS
The APRS system also allows you to see who is around you, their distance from you, and their direction from you.... as the system was designed for situational awareness.
In addition to tracking and sending messages to check in while on your adventures, this type of system would be good for a trail run event where you could see what trail each group was on and where on the trail they were. It would also be good if you were in search and rescue. Others could see where you had been and if every S&R group had an APRS beacon you could see where everyone had been and make sure the area had been covered accordingly.
The International Space Station has an APRS digipeater on board as well and there are a couple of satellites flying around that are also APRS capable digipeaters. For more info check out this thread: APRS via Satellite
Hardware... what do you need for an APRS set up?
You could take the easy way out and just download an APRS app for your phone (remember you have to be a licensed ham to use this) however this requires that you have a cell signal. If you want to go the RF route here is what you will need.
First off you will need a radio, a radio that operates on the 2m band specifically. There are some dual band radios that allow you to run APRS on one side and voice on the other, but most do not. Most dual band radios are dual receive but single transmit which means you can transmit APRS or voice but not both at the same time though you can listen to both simultaneously. A dedicated single band (2m) radio would work great, either mobile or HT. The mobile would have more watts (and likely a better receiver) which would come in handy for areas with sparse digipeater coverage. The radios that do APRS and voice at the same time also typically have the APRS hardware built in, these radios include the Kenwood TM-D710G (mobile), Yaesu FTM-400XDR (mobile), Kenwood TH-D72A/TH-D74A (HT) and Yaesu FT2DR (HT). The mobiles are quite popular.
You will may also need a TNC or Terminal Node Controller. This device takes the digital info from the GPS and converts it into audio tones to be transmitted by the radio and vise versa. Common TNCs are the Byonics Tiny Trak, Argent Data Open Tracker, TNC-PI (Raspberry PI) and Mobilinkd. The TNC takes the digital information and converts it to audio tones to be sent out over RF. If using a smart phone with an APRS app you can connect the phone direction to the radio and the app will do the audio processing, this using the VOX (Voice activated transmit) to transmit the signal where the TNC will actually key the radio like pushing the PTT on a mic. Some of the TNCs require a GPS puck to obtain the data while others such as the Mobilinkd use the phone for the GPS data.
You may also need a display, some TNCs allow displays some don't. I prefer to have a display to see where others are and send messages, the ones that don't have a display are sometimes referred to as a dumb tracker as you can't really do anything else with it except track your vehicle.
The TNC you get may dictate the display you have to have. Some use old nav units such as the Nuvi350 while others can use small computer displays and others can use tablets/smart phones. I run the Mobilinkd and I like it because it bluetooths to the screen so it is housed in the back of the vehicle by the radio and there is no extra cord to run through the cabin of the vehicle.
There are also standalone units with the radio (10w or less), antenna and TNC in one compact unit such as the Byonics Microtrak series.
APRS is by no means the end all solution to tracking and messaging while off grid, but it's another tool to have at your disposal. APRS largely depends on hams to set up the digipeaters/igates and unfortunately there are still areas with no coverage. APRS still works simplex (radio to radio) regardless of any local APRS infastructure so if running around an area with a group you could possibly still use APRS within the group depending on terrain.
Here is an example of APRS from South Texas to Alaska.
This isn't an all inclusive write up but just something to give you an idea of what you might need to begin your own research to get set up using APRS. I and others would be glad to help if you have any questions.
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