QRSS stands for "Quasi-Random Signal Sampling." It is a method used in radio communications, particularly in the field of amateur radio, to transmit low-speed data over long distances. QRSS allows operators to send information using very low power and slow transmission speeds, making it effective for weak signal conditions. The technique involves sending signals at intervals that are not strictly regular, which helps to avoid interference and improve the chances of successful reception. QRSS is often used for experimental purposes and can be a fun way for amateur radio enthusiasts to explore long-distance communication.