A signal analyzing circuit with at least a first channel, said first channel comprising: - a digitizer configured to digitize an input signal into a time-and-value-discrete signal; - a decimator unit; - a digital down converter unit; and - an acquisition memory, characterized in that said first channel further comprises a switching unit, wherein the switching unit is coupled to the digitizer, said switching unit being adapted to receive said time-and-value-discrete signal; wherein the switching unit is coupled to said acquisition memory; and wherein said switching unit is adapted to connect said acquisition memory with either said decimator unit or said digital down converter unit such that said switching unit is adapted to selectively: activate said decimator unit in a time-domain operation mode, said decimator unit decimating said time-and-vale-discrete signal to a decimated time-and-value-discrete signal, wherein said acquisition memory is coupled to said decimator unit in said time-domain operation mode to store said decimated time-and-value-discrete signal, said acquisition memory being not coupled to said digital down converter unit in said time-domain operation mode, or activate said digital down converter unit in a spectrum view operation mode, said digital down converter unit down-converting said time-and-value-discrete signal to a down-converted time-and-value-discrete signal, wherein said acquisition memory is coupled to said digital down converter unit in said spectrum view operation mode to store said down-converted time-and-value-discrete signal, said acquisition memory being not coupled to said decimator unit in said spectrum view operation mode. - a digitizer configured to digitize an input signal into a time-and-value-discrete signal; - a decimator unit; - a digital down converter unit; and - an acquisition memory, said first channel further comprises a switching unit, wherein the switching unit is coupled to the digitizer, said switching unit being adapted to receive said time-and-value-discrete signal; wherein the switching unit is coupled to said acquisition memory; and wherein said switching unit is adapted to connect said acquisition memory with either said decimator unit or said digital down converter unit such that said switching unit is adapted to selectively: activate said decimator unit in a time-domain operation mode, said decimator unit decimating said time-and-vale-discrete signal to a decimated time-and-value-discrete signal, wherein said acquisition memory is coupled to said decimator unit in said time-domain operation mode to store said decimated time-and-value-discrete signal, said acquisition memory being not coupled to said digital down converter unit in said time-domain operation mode, or activate said digital down converter unit in a spectrum view operation mode, said digital down converter unit down-converting said time-and-value-discrete signal to a down-converted time-and-value-discrete signal, wherein said acquisition memory is coupled to said digital down converter unit in said spectrum view operation mode to store said down-converted time-and-value-discrete signal, said acquisition memory being not coupled to said decimator unit in said spectrum view operation mode. activate said decimator unit in a time-domain operation mode, said decimator unit decimating said time-and-vale-discrete signal to a decimated time-and-value-discrete signal, wherein said acquisition memory is coupled to said decimator unit in said time-domain operation mode to store said decimated time-and-value-discrete signal, said acquisition memory being not coupled to said digital down converter unit in said time-domain operation mode, or activate said digital down converter unit in a spectrum view operation mode, said digital down converter unit down-converting said time-and-value-discrete signal to a down-converted time-and-value-discrete signal, wherein said acquisition memory is coupled to said digital down converter unit in said spectrum view operation mode to store said down-converted time-and-value-discrete signal, said acquisition memory being not coupled to said decimator unit in said spectrum view operation mode.