Two-way APRS-IS

Two-way APRS-IS is the messaging half of the Full APRS Controlled Beta. In it you can:

• reply to an APRS message sent to you;
• start a new message to any station, by its callsign and SSID;
• acknowledge messages sent to your station, which HAMORA does for you;
• see whether the other station acknowledged yours, while HAMORA tries again for you.

This page covers APRS-IS, the internet side of APRS. The first Full APRS release also includes sending through your own radio, with HAMORA Bridge and your TNC (In Testing · not approved for use): see APRS over radio.

• Your amateur radio licence.
• A HAMORA account, with your callsign verified for that account and the licence statement accepted. See Verifying your callsign.
• Your own APRS-IS passcode. HAMORA doesn’t create passcodes: you enter the one you already have.
• An internet connection, with HAMORA open on screen.
• A HAMORA build that can send. Today’s public beta builds can’t: sending is only in builds made for testing.

Sending is off until you switch it on, in the APRS station settings (APRS→Map settings→Two-way APRS-IS in the builds being tested; names may change). Before it goes on, HAMORA asks you to confirm that what you send is public, archived, may be passed to radio by IGates, and is your responsibility under your licence.

HAMORA sends only when every one of these holds:

1. the build allows sending;
2. you switched sending on;
3. you set your callsign and SSID;
4. you’re signed in, and HAMORA has verified that callsign for your account;
5. you accepted the licence statement;
6. a passcode is saved for that callsign;
7. an encrypted connection to APRS-IS is available;
8. the APRS-IS server itself says your callsign is verified on this connection;
9. HAMORA’s own sending limits allow it, and HAMORA’s kill switch isn’t stopping it.

A passcode alone never turns sending on. If you sign out, your verification lapses or you switch sending off, the sending connection closes at once. Receiving carries on.

Your passcode

• It’s kept in your phone’s secure storage (Keychain or Keystore), never in HAMORA’s database.
• It’s never synced, logged or sent to HAMORA Cloud.
• It’s sent only to an APRS-IS server over an encrypted connection. If none is available, sending stops and receiving carries on.
• Once saved, the screen shows only “Passcode saved” and a Forget button.

Never share your passcode, and never put it in a screenshot or a report.

Open APRS→Messages→New message, or tap Message on a station’s card.

• To: a callsign with its SSID, such as JA1ABC-7. Bulletins and your own station aren’t accepted.
• Text: 1 to 67 plain characters (letters, digits and common punctuation), without |, ~ or {. A counter shows what’s left, and anything refused is explained.
• Every packet is checked before it leaves.

Your messages

APRS has no delivery receipts. A message is confirmed only when the other station sends back an acknowledgement. Until then HAMORA tries again, up to 6 tries in all, waiting longer each time.

• Retries happen only while HAMORA is open on screen.
• If the retry window passes while HAMORA is closed, the message expires.
• Stop retrying ends the retries for a message whenever you want.
• An acknowledgement counts only if it comes from the exact station you wrote to, is addressed to your exact station, and carries the same message number.

Each message shows where it stands (the wording in the builds being tested):

HAMORA never says “delivered”: only an acknowledgement shows the other station got a message.

Messages to you

• HAMORA acknowledges each message addressed to your exact callsign and SSID that asks for an acknowledgement.
• It never acknowledges messages to your other SSIDs, its own packets, or anything while it’s receive-only.
• A station you’ve blocked never gets an acknowledgement.
• Acknowledgements have their own limit, so a flood of messages can’t use up your own sending.

A conversation goes out on one link only: APRS-IS, or your own radio through HAMORA Bridge. Never both, and HAMORA never switches to the other link if one fails. An acknowledgement goes back on the link the message arrived on.

The first Full APRS release includes both links. Radio stays off until HAMORA approves it. Its status: In Testing · not approved for use.

• Messages you send stay on your phone: up to 1,000, for 30 days. You can clear them.
• HAMORA Cloud doesn’t receive your messages.
• Stopping: switch sending off, or see APRS safety for the kill switch.