Electrical Apparatus-Namely, Audio and Radio Generators, Oscillators, Detector Assemblies and Circuits, Rectifiers and Direct and Alternating-Current Amplifiers; Voltage, Current and Electronic Power-Supply Systems; Vibration Pick-Ups for Generating Voltages in Response to Mechanical Vibrations; Audio-Frequency and Radio Frequency Transformers; Connectors, Insulators, Binding Posts, Switches, Contactors, Contact Members, Knobs, Sockets, Rheostats, Potentiometers for Use in Radio and Similar Apparatus, Resistors, Attenuators and Voltage Dividers; Capacitors, Inductors and Chokes; Electric and Electronic Control Boxes and Motor-Speed Control Circuits; Radio and Other Dials for Use on Electrical Components and Instruments; Electro-Mechanical Hummer Oscillators; Piezo-Electric Crystals; Electric Filters; Storage and Dry-Cell Batteries; Electric Cables; Cathode-Ray Tubes; Transmission-Line Phase, Insertion and Terminal Units; and Tuned Electric Circuits for Suppressing Harmonics and Other Frequency Components, Noise and Hum