Detection

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Gustave Lytton wished to avoid detection and so relayed his distress call. (TV: Attack of the Cybermen ^[+]Loading...["Attack of the Cybermen (TV story)"])

A poster about detecting radiation. (TV: School Reunion ^[+]Loading...["School Reunion (TV story)"])

By 2007, a poster by BNFL in Deffry Vale High School included information on detecting radiation. (TV: School Reunion ^[+]Loading...["School Reunion (TV story)"])