Home Ailunce HA2 APRS Functionality Revisited

[Moleculo]

When I first reviewed the Retevis Ailunce HA2, APRS was one of the radio's most interesting features, but it was also clearly unfinished. The radio could transmit position beacons and display received stations, but proper APRS messaging was missing. Incoming messages were treated more like packet comments, there was no way to compose a message, and Bluetooth access to the internal TNC was still a promised future feature.

The good news is that Retevis has now released new firmware that addresses most, if not all, of the missing APRS messaging functionality. I helped test several versions of this firmware and provided feedback about what the APRS implementation needed to do. After using the released version, I can report that all of the new messaging features described below work.

Full APRS Messaging from the Radio​

The HA2 now has a dedicated APRS Messages menu. From here, you can compose a new message, select a predefined Quick Message, review sent and received messages, or clear the stored message history.



Selecting New opens a proper message-composition screen with separate fields for the destination station and message body.


The radio allows you to store up to 20 Message Contacts:

Editable Quick Messages​

Typing a message with a handheld radio keypad is never going to be as convenient as using a phone, so the addition of Quick Messages is particularly useful. The HA2 includes ten editable messages that can be selected and sent without typing the complete message each time.







The supplied text is only a starting point. A user could replace the defaults with messages such as "At checkpoint," "Need assistance," or "Changing frequency," depending on the activity. This could be especially useful for public-service events, group outings, search-and-rescue exercises, or simply coordinating with other operators while traveling.

Receiving, Acknowledging, and Replying to Messages​

Received APRS messages are now displayed properly instead of in the status text, with the sending station, acknowledgment status, and message text shown in separate fields.



This is a significant improvement over the original firmware, which attempted to place incoming message text into the comment portion of a received APRS packet.

Selecting a stored message or a beacon brings up a new Message Action screen (the screen is slightly different when doing this from a beacon)



This is the type of basic messaging workflow that should have been in the radio from the beginning, but what matters is that it is here now—and it works. You can exchange messages, see acknowledgment status, review sent and received message history, and reply without starting over from the main APRS menu.

The HA2 has gone from being primarily an APRS position tracker to a radio with useful two-way APRS messaging.

Finally, an APRS Audio Control​

Another small but welcome addition is a dedicated APRS Audio setting.


Unfortunately right now it doesn't seem to do anything, so I'll be reporting this issue. I think it's supposed to turn off the incoming APRS audio.

The Phone App Is Still Only a Programming App​

The Retevis phone app can connect to the HA2 over Bluetooth and perform basic programming of the APRS settings. However, it is important to understand that the app is not an APRS client. You cannot use the Retevis app to send or receive APRS messages. Messaging must be performed from the radio itself or through a separate APRS application connected to the TNC. The phone app also cannot configure the Smart Beaconing parameters. To change those settings, you still need to use the desktop programming application or CHIRP. The phone app is convenient for making basic changes in the field, but it does not replace the complete desktop software—and it should not be confused with an application like APRSDroid.

Bluetooth Access to the TNC​

The other major firmware improvement is that the HA2's internal TNC is now exposed through Bluetooth. This allows the radio to function as a wireless KISS TNC for compatible applications. But it seems that this still needs some refinement. I tested the HA2 with APRSDroid, and it works for both APRS tracking and messaging. This gives you the larger screen and easier keyboard entry of an Android device while the HA2 handles the RF side of the connection. For normal APRS operation, this is a very useful combination and eliminates the need for audio cables or an external modem.

I also tested the HA2 as a Bluetooth KISS TNC with Winlink on Android, better known as WOAD. WOAD sees the HA2 and initializes the TNC, so the Bluetooth connection and basic KISS interface appear to be working. However, I have not been able to successfully establish a connection with a Winlink packet server. The HA2 appears to transmit the initial connection request, but its TNC does not respond correctly when the remote station answers. To eliminate the server and my operating position as variables, I tried sending the exact same message from the same seat using both the HA2 and my Kenwood TH-D75. The Kenwood successfully established the connection and sent the message. The HA2 did not.

Based on that testing, there still appears to be an issue in the HA2 TNC implementation that affects packet connections requiring a connected exchange. APRS tracking and messaging work, but I cannot currently recommend the HA2 as a reliable Bluetooth TNC for WOAD and Winlink packet operation. Hopefully this is something Retevis can address in another firmware update.

Conclusion​

This firmware represents a major improvement to the Ailunce HA2. For the money, the radio is now a pretty easy and inexpensive way to get into APRS. It can operate as a self-contained APRS messaging handheld, or it can be paired with APRSDroid when you want the convenience of a phone interface. Add the fact that it has an IP67 rating, long battery life, and is very rugged, this is turning into a very capable little radio.