Dynamometers; Frequency meters; Galvanometers; High-frequency switching power supplies; High frequency switches; Ohmmeters; Oscillographs; Pressure measuring apparatus; Surveying machines and instruments; Variometers; Voltmeters; Air quality measurement apparatus, namely, particle counters; Diesel-engine exhaust test instruments; Electric meters; Electrical inductors; Electronic test and measurement devices for use in the fields of networks and telecommunications, namely, instrumentation used...