Power distribution and control machines and apparatus, namely, [ electric connectors, plugboards,] lightning arresters; [ phase modifiers, batteries and cells, electric and magnetic meters and testers, ] electric wires and cables, antennas, [ aerials,] receiving apparatus, namely, level setters, amplifiers, filters, mixtures, channel preset amplifiers, pilot signal generators, channel proper amplifiers, converters; head end apparatus, namely, channel processors, subrack signal processors, sub...