"PulseModem A" is an APRS client, that reads and reports APRS location and messages. APRS is a digital communications protocol that can exchanges information among large number of stations both local and global. You as a licensed Amateur Radio operators can send and receive APRS location and message in 2 ways: - Direct to the APRS-IS Network - Sent via amateur radios supporting VHF Band at 144MHz. Full AX.25 software AFSK modem is available for off-the-grid operations. Internet optional! APRS is a registered trademark of Bob Bruninga.