Product Introduction: Mygica A681B is an external TV tuner that can help you watch TV programs that can only be seen on home TV sets on PCs and laptops. It receives TV signals through an antenna and decodes and plays them on the computer through specific software (download required). In the United States, the TV signal formats supported by A681B are: ATSC 1.0, QAM. Important: To use this product, you need to install the driver and download the playback software. Please read the instructions carefully and install the driver and playback software -- HiDTV according to the instructions.