The APRS most of us know is not the APRS that was intended to be. That's one of the interesting little vagaries of amateur radio -- things that start out as one thing can transform into totally different applications that were never predicted.
When Bob Bruninga (WB4APR) created APRS back in the early '90s, it was never supposed to be a vehicle tracking system. But that's how amateurs used it, distinguishing itself from AX.25 keyboard-to-keyboard (K2K) packet. Those interested in the tactical comms aspect of APRS instead gravitated towards K2K, creating digipeaters, bulletins boards (BBS), mail systems... and eventually, things like WinLink.
APRS continued to evolve, however, adding the CWOP (Citizens Weather Observing Program), for example. This is the network of home weather stations (most of which aren't licensed amateurs) connected through the internet (mostly). The introduction of the CWOP was part of a general overhaul of APRS protocol in the '90s that added the N-Path system, objects, STATUS, etc. and that further refined messaging. New proposals to overhaul APRS continually appear, though they had been squelched by Bruninga. With his death, it seems unclear how any such protocol overhauls would be implemented. The last one took several years to be completely accepted, and involved significant contention. Many, but not all, of these overhaul proposals seem to involve making APRS similar to WinLink, and would likely require a shift to 9600 baud (or more).
Still, acting within the basic established framework of the current APRS protocol, many new aspects have been developed. Most of these new services leverage the functionality of the APRS messaging protocol to work.
For example, SMSGTE. Born in 2014, SMSGTE allows APRS messaging to connect to the SMS cellphone network. Anyone (even non-hams) can send a short text message from their phone to any (messaging-capable) amateur APRS station in the countries covered by the service. And vice versa, of course. Some contention has arisen regarding non-hams using amateur frequencies. How does this differ from the phone patches of old, when hams connected to a phone patch to make phone calls to non-hams? In the pre-cellphone days, this was a big incentive for people to learn the code and get their Novice ticket. You could make phone calls from your car! Wow, how advanced!
Other current services include things like MPAD, WA1GOV, T.ME, APRSH, and WXBOT. The simple truth is that many developers can come up with relatively simple scripts using things like Python to implement novel applications by using the relatively simple APRS messaging protocol. In addition, DMR networks have added the ability of non-DMR operators to message DMR stations through APRS, and for DMR operators to send position packets to APRS. A basic email protocol has existed for decades. QSO confirmations can also be sent using APRS messaging around the world. Satellite digipeaters in LEO (Low-earth orbit) exist to allow operators in remote areas to message other operators hundreds of miles away using APRS messaging protocols. General-target messaging allows a single operator to send bulletins, announcements, and information to potentially thousands of people using APRS messaging.
Other applications, like real-time 2M propagation, have long been possible.
In the metro area, with a plethora of TX and RX-only gateways, any licensed amateur radio operator can send a tweet, connect with Telegram, get a weather forecast, find out which repeaters are nearby, determine the times of sunrise or moonrise, or find out when a particular satellite will be passing over their location by using APRS messaging. They can also participate in global nets, send an SMS message, or use queries to determine if a particular operator has been on-air recently.
Further, some hotspot/MMDVM clients (like Shark RF) have some sort of APRS messaging capability available through a web interface. Many are not aware of this, however, and wonder how their station location is showing up on aprs.fi.
This is why new gateways in rural areas are such a game-changer. Even a basic RX-only gateway can connect RF APRS operators to a world of possibilities. TX gateways are even more valuable, allowing the exchange of information to take place over RF in places where cell data is spotty or challenging. "APRS messaging capability" is much more than being allowed to send one-on-one messages to other operators.
The obstacles
- A lot of amateurs use APRS solutions that aren't messaging-capable. For example, many of the D-Star/Pi-Star MMVDM clients have no messaging capability. In other cases, trackers such as the TinyTrak have no messaging capability. Native solutions, such as Kenwood and Fusion rigs, allow only canned messages or proprietary messaging.
- I-Phone operators don't pay for additional messaging capabilities.
- Amateurs who have Android phones are either unaware of solutions such as APRSDroid, or are unclear how to use those apps to access messaging capabilities.
- Operators who access APRS with Linux-based clients are unaware of how to use the built-in messaging capability of that software.
- Many messaging-capable stations, such as gateways and digipeaters, are unattended and don't respond to messages.
The answer
As with many issues involving APRS, the answer is simple but implementing it is complicated. Amateurs with Windows computers should install the free APRSIS32 or UIView software. These software packages will run on old PCs that you would otherwise throw out. An old Android smartphone is likewise a candidate for APRSDroid, and adding a Bluetooth keyboard will make messaging a lot more enjoyable. Most hams have access to an old PC, an old Android phone, or an old Chromebook that can handle a Linux install. Clients such as YAAC can work on Win XP, Ubuntu, FreeBSD9.0, Raspbian, or Mac OS X. These don't even involve a radio, and will connect to the APRS-IS for messaging.
You can keep your old Byonics tracker, but add a home/portable solution for messaging.
While the Mobilinkd TNC 3 is not currently available, the Kantronics KPC-3+ or Microsat TNC is still around. Either of these will allow any HT or mobile/base rig to instantly become an RF-based APRS station. These will also work with HF rigs. Applications such as DireWolf will also provide APRS access. The KPC3+ will also allow you to connect to K2K stations using AX.25 packet.
As APRS evolves, those without any APRS messaging ability will be left out. Possible future expansions might include traffic reports, integration with EchoLink, propagation reports, satellite distribution, navigation, access to ships, file-sharing via html links, GIS data, or text-to-voice messages over FM repeaters (including 6M and 10M repeaters). Government agencies (such as the NWS or Homeland Security) might use text-to-voice to transmit warnings over FM repeaters (including GMRS) to the populace. SKYWARN and other EmComm EMS organizations might use APRS messaging to leverage location-based data to gather information. Nationwide nets using APRS (and satellites) might spring up to allow isolated operators to contribute to and receive "ground truth" information without the need for HF operation.
The implications
It's entirely possible a second (or third) APRS frequency might be designated to accommodate APRS messaging traffic. While APRS traffic now exists on 144.39 and 145.825 (for satellite), we may have to add 144.37 or 145.70 to exclusively handle messaging traffic. A parallel network of digipeaters and gateways might need to be set up, connected to the APRS-IS. Already, we are seeing busy metro areas being unable to handle the increased traffic from things like APRS Thursday. Remember, APRS takes place on a single simplex frequency.
And, since APRS is essentially FM analog simplex traffic, any expansion will require the same bandwidth as an analog FM simplex channel. A possible alternative is to make one simplex FM channel shared with APRS messaging. Voice Alert traffic already uses 145.520 (the FM calling channel).
The big question is, "Who has sufficient stature to make this happen?".
The League seems to be unaware that operations above 50 MHz exist. Repeater councils are chronically late to the game. We see this with new developments such as simplex digital modes (DMR, P25, Fusion, etc.). The MN Repeater Council fails to recognize the current APRS activity on 144.39 as legitimate, and this has existed for decades already. National packet organizations like TAPR can't agree on a common K2K frequency. Many states don't even acknowledge 145.825 as a national satellite APRS frequency.
There's more of a consensus of the band plan for EME on 2M than there is for the much more popular APRS network. I would hope that we don't need to move any APRS expansion to 6M, 1.25M , or UHF.
Like most new developments, I think that the Powers-That-Be will conform to the masses.
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