Provides symbols for general quantities and for quantities concerning two-port networks, line transmission of signals (including cables), radio wave propagation, waveguide propagation, aerials, electro-acoustics, equivalent circuits of piezo-electric crystals, scattering matrix and transfer matrix, static convertors, automatic control science and technology. It supplements AS 1046, Part 1, and is closely aligned with IEC 27-2 and 27-2A.