Parliamentary sound system in the Argentine Chamber of Deputies
01 January 1941
Describes a system of loud-speakers microphones designed to ensure audibility speaker in the chamber; 193 microphones with a relay switch, are provided, one for member; 4 loud-speakers are concealed walls above the level of the speakers and are so adjusted that sound appears to come approx. from the speaker's actual position. Full details of the circuits and general appearance of the units are given.