crystal oscillator, variable resistor, thyristor, condenser microphone, voltage divider, impedances, josephson junction, electret, sine wave, servomotor, toroid, ammeter, phototransistor, passband, sinusoid, midplane, subminiature, inductances, toroidal, heterodyne, bypass capacitor, resonant cavity, demultiplexer, pyrometer, vacuum tube, dipole antenna, resonator, amplifier, baud rate, microchannel, absorption coefficient, ferrites, combiner, rectifier, preamplifier, preamp, zener diode, freq, quadrature, venturi, handwheel, capacitances, dipole moment, inductor, electrolytic capacitor, peltier, klystron, polyphase, pulser, stators, pcb, amps, rotary actuator, phono, potentiometer, millivolt, microwatt, strain gage, voltages, dipolar, cardioid, ohm, cuvette, windings, microswitch, bistable, chalcogenide, photomultipliers, centrifugal pump, photoconductive, voltmeter, oscillator, magnetron, dispersive, piezoelectric crystal, breadboard, photodetector, photodiode, synchronous motor, cassette deck, monochromator, opto, mounter, flyback, directivity, pmos, mux, scart, thermocouples, bimetal, capacitor, sideband, pulse generator, galvanometer, resistor, actuator, expander, electromotive force, zener, thermistor, sepic, photomultiplier, diode, triodes, oscilloscope, rectifiers, transformer, transistor, aerofoil, diodes, alternator, anode, extruder, heater, solenoid, carburetor, cathodes, condenser, cathode, thermionic, emitter, follower, mixer, tube, amp, bias, cutoff, inverter, modulated, modulator, outlet, pass, quenching

de forest, lee de forest, the father of radio

electron tube, thermionic tube, thermionic vacuum tube, thermionic valve, tube, vacuum tube