Unidentified MFG - 6-158 - Audio, Microphone Element. Crystal, Piezoelectric, New

Unidentified MFG - 6-158 - Audio, Microphone Element. Crystal, Piezoelectric, New Vintage Vintage Microphone Element - 6-158 - Audio, Microphone Element. Crystal, Piezoelectric Piezoelectric Microphones, also called Crystal Microphones, were used primarily between 1930 and 1960. At the time, these were important to the home recording and small-scale paging market, but were later replaced by lower-cost dynamic and electret capacitor microphones. Capacitive Nature: A crystal microphone functions like a capacitor, generating a voltage when subjected to sound pressure (piezoelectric effect). While capacitors allow current to flow when charging and discharging in an AC circuit, the inherent insulating property of the crystal itself presents a very high impedance to a direct current measurement from an Ohmmeter. Crystal microphones rely on the piezoelectric effect: This means they generate a voltage when mechanically stressed, like when sound waves cause their diaphragm (attached to the crystal) to vibrate. Type: Audio, Microphone. Crystal, Piezo High Z. (Will Measure Open using an Ohm meter, approximately 260 pF) Blue Plastic Body. Overall Dimensions: 22.7mm Diameter, Round x 11.1mm High. (0.875” x 0.437”) New Old Stock Vintage – Difficult Microphone Elements to find. Manufactured in Taiwan Applications: Great for radio and electronic project experimenter use, vacuum tube circuits, anywhere a high impedance microphone is required. Home recording systems, Amateur communication, Mobile communication. Piezoelectric crystals are durable and have a relatively large electrical output; for this reason, they were often used in telephones and portable sound systems. They do not have very good linearity and so are inadequate for quality high fidelity sound recording. Discounts provided for Lot purchases of 2, 3, or 4 with the Make Offer” option limited to bulk purchases.