Sentence:  Six radiomen told how , twice on two days after the ring was nabbed , a transmitter near Moscow was heard calling , using signals , times and wavelengths <WSD>specified</WSD> on codes found hidden in cigaret lighters in Lonsdale 's apartment and the Krogers ' house and also fastened to the transmitter lid . 
Meaning of the word marked with <WSD> tags:  decide upon or fix definitely