'Marconi' Direction Finder Type DFM2, by Marconi Company, London, c. 1927

Marconi' Direction Finder Type DFM2, in grey-enamelled copper alloy and teak case with hinged lid upon upper surface (revealing interior). Interior includes copper alloy tuning condenser, assorted glass valves, coils and other circuitry. With assorted, primarily Bakelite controls upon front vertical metal surface. Controls include filaments dial (scale 1-8), mode dial (standby, direction finder, sense), on/off dial, s.c tuning condenser dial (scale 0-10), glass-faced radiogoniometer (scale 0-360), tuning condenser dial (scale 450-1200 metres), coupling dial (scale 0-90), second tuning condenser dial (scale 600-1200 metres), third tuning condenser dial (scale 450-1200 metres), tuning adjustment dial (scale -5,0,5), note magnifier on/off switch. Controls are marked with celluloid name plaques. With two S625 screened grid valves.