BBC ATP/1 Amplifier Test Panel, 1960. Used for testing the plug-in amplifiers type C/9 and GPA/4 used with BBC 'Type B' studio equipment. It will accommodate two amplifiers of this type and provides power supplies for both together with switching and metering facilities. The panel contains input and output jacks for both positions and for an attenuator pad for use when testing C/9 amplifiers. A programme meter is provided for testing MNA/3 amplifiers.
It was also one of the rack-mounted components which formed part of BBC's AC Test Bay AC/55, a 19-inch bay of equipment for the audio-frequency testing of sound apparatus and the audio-frequency and direct current testing of lines. At small centres where the full facilites were not required the bay was supplied partially equipped as necessary to suit the requirements of the particular station.