ShipPlotter decodes the AIS digital signals from each ship using the sound
card in your PC. You need a suitable VHF band radio receiver tuned to one
of the two AIS channels. The program decodes the received digital data and
displays it in a variety of formats.
Signal mode - In Signal Mode, ShipPlotter displays the raw digital signals
on your PC screen in a diagnostic display which helps you to set up the
system.