Hand drawn diagram from 1963 showing police communications, going from police boxes, AA boxes etc to a switchboard and via VHF transmitter to various cars.
Hand drawn diagram from 1963 showing police communications, going from police switchboard to different departments, teleprinters and via radio links to other forces and interpol.
From the #ZCars annual I bought last week: I love these diagrams of how police communications infrastructure worked at the time! Also includes a #DoctorWho crossover! #ArchiveTV