Sentence:  Prior art radio and telephone communication headsets typically incorporate a microphone and receiver which require amplifier or other appropriate electronic impedance matching circuits for interface with the console, or at least electrically conductive wires to similar electronic <WSD>circuitry</WSD> located in the console. 
Meaning of the word marked with <WSD> tags:  A specific system of electrical circuits in a particular device;  the design of such a system.