APRS Standard Callsign SSID To assist in identifying a stations functionalities/capabilities designated callsign SSIDs are used in APRS . Use the correct SSID for your stations functionality/capability. -0 Home Station, Home Station running IGate. -1 Digipeater, Home Station running a Fill-In Digi, Wx Digipeater -2 Digipeater [#2 or] on 70CM -3 Digipeater [#3] -4 HF to VHF Gateway -5 IGate (Not home station) -6 SatGates & Special function Station. -7 Kenwood D7 HH -8 Secondary Mobile station. -9 Primary Mobile station. -12 Portable Units such as Laptops etc. -14 Trucks -15 Mobile HF station. Note: In TNC Only mobile systems running a GPS sending raw NMEA strings, the SSID is used to establish the Vehicle symbol. These are not very common although you will see a few mobile stations with odd SSIDs. Read the APRS spec for more info.