PulseModem A

PulseModem A is the APRS client for licensed Amateur Radio operators on iPhone and iPad.

Connect to the global APRS-IS network and watch nearby stations appear on a live map in real time — each one drawn with its authentic APRS symbol icon and a country flag derived from its callsign prefix.

LIVE APRS-IS FEED
- Connects to rotate.aprs.net with a geographic filter centred on your GPS location
- Displays raw packets as they arrive, colour-coded by type
- Auto-connect on launch — PulseModem A is ready before you finish your coffee
- Decodes uncompressed, Base91 compressed, and Mic-E packets (common in Kenwood and Yaesu radios)


INTERACTIVE MAP

- Every station plotted with its real APRS symbol PNG — car, hiker, weather station, digipeater, and hundreds more
- Tap any pin to see a callout; tap the callout to open the full station detail
- Centres on your location at city level the moment a GPS fix is available
- Your own beacon appears on the map immediately after sending

STATION LIST
- Full searchable list of received stations
- Country flag next to every callsign, resolved from the standard cty.dat prefix database
- iPad split-view: select a station on the left, see full details on the right
- One tap to look up any callsign on QRZ.com — right inside the app, no browser switch

GPS BEACONING
- Send your position to the APRS network with a single tap
- Choose your station symbol from a searchable visual grid of all APRS symbols
- Add an optional comment to your beacon packet
- Encoded in Base91 compressed format for maximum compatibility

SETTINGS & COMPATIBILITY
- Callsign and passcode stored securely in the Keychain
- Upgrading from an earlier version? Your callsign, passcode, and preferences carry over automatically
- Adjustable filter radius, fallback coordinates for GPS-denied environments
- Supports receive-only mode (passcode -1) — no transmit license required to monitor

REQUIREMENTS
A valid amateur radio license is required to transmit on APRS. Anyone may receive and monitor.

RF Receive and RF Transmit (direct audio-port TNC operation) are under re-development and will return in an upcoming update.

APRS is a registered trademark of Bob Bruninga.