Basic Flowchart Symbols and Meaning

The vector stencils library "Lamps, acoustics, readouts" contains 35 element symbols of lamps, acoustic components, electrical measuring instruments for drawing electrical schematics and electronic circuit diagrams.
"Electrical measurements are the methods, devices and calculations used to measure electrical quantities. Measurement of electrical quantities may be done to measure electrical parameters of a system. Using transducers, physical properties such as temperature, pressure, flow, force, and many others can be converted into electrical signals, which can then be conveniently measured and recorded." [Electrical measurements. Wikipedia]
"A lamp is a replaceable component such as an incandescent light bulb, which is designed to produce light from electricity." [Lamp (electrical component). Wikipedia]
"An electric bell is a mechanical bell that... functions by means of an electromagnet. When an electric current is applied, it produces a repetitive buzzing or clanging sound." [Electric bell. Wikipedia]
"A buzzer or beeper is an audio signalling device, which may be mechanical, electromechanical, or piezoelectric." [Buzzer. Wikipedia]
"Electronic sirens incorporate circuits such as oscillators, modulators, and amplifiers to synthesize a selected siren tone (wail, yelp, pierce/ priority/ phaser, hi-lo, scan, airhorn, manual, and a few more) which is played through external speakers." [Siren (noisemaker). Wikipedia]
"A microphone (colloquially called a mic or mike...) is an acoustic-to-electric transducer or sensor that converts sound in air into an electrical signal. ...
Most microphones today use electromagnetic induction (dynamic microphone), capacitance change (condenser microphone) or piezoelectric generation to produce an electrical signal from air pressure variations." [Microphone. Wikipedia]
The symbols example "Design elements - Lamps, acoustics, readouts" was drawn using the ConceptDraw PRO diagramming and vector drawing software extended with the Electrical Engineering solution from the Engineering area of ConceptDraw Solution Park.