Polish quartz crystal resonator from a <a href="https://en.wikipedia.org/wiki/crystal_oscillator" class="extiw" title="w:crystal oscillator">crystal oscillator</a> with case removed, showing construction. It consists of a round transparent plate of quartz, with metal foil electrodes plated onto both surfaces attached to terminals on the bottom. When connected to an <a href="https://en.wikipedia.org/wiki/electronic_oscillator" class="extiw" title="w:electronic oscillator">electronic oscillator</a> circuit, the quartz plate vibrates mechanically millions of times per second, creating an oscillating electrical signal in the circuit.
<a href="https://en.wikipedia.org/wiki/cs:User:Serych" class="extiw" title="w:cs:User:Serych">Jakub Šerých</a> at <a href="https://en.wikipedia.org/wiki/cs:" class="extiw" title="w:cs:">Czech Wikipedia</a>
23 July 2006 (original upload date)
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