The LD-34 is a 4-channel RS-232/V.24 switch. The unit has one input channel that connects with one or all of the four output channels. The selection of output channel is made by either external digital signals or RTS-activation of the output channel. The LD-34 also features an expansion channel, which provides onward connection of the input channel to further LD-34 units or other equipment. Transmission rates up to 115.2 kbit/s are supported on all channels.