The present document states the minimum requirements for equipment to be used for generation, transmission and reception of Digital Selective Calling (DSC) for use on board ships. DSC is intended to be used in the Medium Frequency (MF), High Frequency (HF) and Very High Frequency (VHF) bands of the Maritime Mobile Service (MMS), for distress, urgency and safety communication and general communications. The present document is part 1 of a multi-part deliverable that covers the requirements to be fulfilled by: - DSC equipment integrated with a transmitter and/or a receiver; - DSC equipment not integrated with a transmitter and/or a receiver.