Abstract: A telecommunication system to operate a selected operating device including a digital code generating device to generate first and second coded signals having an actuating input to receive an actuating signal, a digital coded signal output where upon receipt of an actuating signal at the actuating input the digital code generator supplies the first coded signal to the digital coded signal output, and a receiver code input; receiver connected to the digital coded signal output having a receiver input to receive the first and second coded signals, a receiver code output connected to the receiver code input, and receiver code generator device to generate first receiver code signal to the digital code generator receiver code input in response to receipt of the first coded signal and supply a second receiver coded signal to the digital code generator receiver code input in response to receipt of the second coded signal where the first receiver coded signal causes the digital code generator to generate the second c