TH-D7A/E in detail: APRS (Automatic Packet/Position Reporting System) Using APRS, the TH-D7 A/E lets you transmit your co-ordinates to a friend, who can then pinpoint your position using a map on a computer. APRS software has been developed for a variety of platforms; however, what makes the Data Communicator so special is that it enables APRS operation without requiring a computer. And when you receive your friend´s positional data, you can display latitude/longitude, direction and distance on your own Data Communicator. Positional/directional data Just hook up to a GPS receiver (NMEA-0183 compatible) and you can transmit your position for automatic calculation of distance, current speed and heading with icons, short comments or fixed messages. Manual input of latitude/longitude is also permitted. Versatile messaging Transmit alpha messages (up to 45 characters) and bulletins. Alternatively, short comments (up to 20 characters) and fixed messages (8 patterns) can be sent together with your positional data. Station list Store received APRS data in up to 40 memory channels. Other Features: - Grid square locator display - TX interval (0.5/1/2/3/5/10/20/30 min.) - Packet pass selection for DigiPeat - Weather station, PHG* data (fixed stations) & Object data reception - Built-in 1200/9600bps TNC (1 packet, 1 frame, 256 bytes) compliant with AX.25 protocol - High-speed (9600bps) PC-based packet communications for chat, BBS, etc - Monitoring DX cluster - Dual receive on same band (VHF only) for both voice and data (two frequencies simultaneously) - 1750Hz tone burst (TH-D7E only)   PHG (P=Power, H=Height, G=Gain) Please note that not all features and options may be available for the model sold in your region. Operation of DTSS, Pager, DTMF, and CTCSS is subject to local regulations.