The invention concerns a system for transmitting information in a digital radio network system (12) between at least two modes of operation, which may be--a direct mode operation (DMO) between two terminal devices (10.1, 10.2) operating independently of the physical radio network system (21) and--a trunked mode operation (TMO) supporting distribution of network resources and operating in the physical radio network system (21). The transmission takes place with the aid of a special gateway unit (22), wherein the gateway unit (22)--listens to each or to a chosen mode of operation (DMO, TMO),--receives the transmission occurring in one mode of operation (TMO, DMO), and--transmits the received transmission to the other mode of operation (DMO, TMO). The gateway unit (22) is formed of two terminal devices (12.1, 12.2) supporting each mode of operation, and whose data transfer interface (23.3*, 23.3') have an audio input (AUDIO In) and output (AUDIO Out) as well as a receiving indication output (RX On) and a transmission connection input (PTT). The terminal devices' (12.1, 12.2) receiving indication output (RX On) is connected to the other terminal device's (12.2, 12.1) transmission connection input SIT), and wherein the terminal devices' (12.1, 12.2) audio output (AUDIO Out) is connected to the other terminal device's (12.2, 12.1) audio input (AUDIO In).