Various electronic components
c= By Kae - Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=655329
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Various examples of Light-emitting diodes (LED)
c = - Own work
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A quartz crystal (left) and a crystal oscillator (right)
c= Vahid alpha at English Wikipedia
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2 different miniature pushbutton switches
c= Vahid alpha
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