What is a commonly used method of sending signals to and from a digital satellite?

The commonly used method of sending signals to and from a digital satellite is FM Packet. This technique utilizes Frequency Modulation (FM) along with packet radio protocols to transmit digital data effectively. FM Packet is particularly suited for communication with satellites because it allows for robust signal handling and is efficient in utilizing bandwidth, making it a dependable choice for transmitting data in space environments where signals may be weak or subject to interference.

The FM mode is compatible with many satellite systems that have been designed to receive and relay digital packets. It typically involves using specific frequencies and protocols that the satellite is equipped to handle, ensuring that the data packets are transmitted and received correctly.

Other methods such as USB AFSK, PSK31, and WSJT are indeed used in various digital communications settings but are not specifically optimized for satellite communication in the same way FM Packet is. USB AFSK is often utilized in sound card digital modes, PSK31 is a specialized digital mode for keyboard-to-keyboard communication, and WSJT is typically used for weak signal digital modes, particularly in Earth-based situations rather than with satellites.