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Silver mica capacitors are still indispensable in some custom applications. Circuit designers still turn to mica capacitors for high-power applications such as RF transmitters and electric instruments and amplifiers because cheaper ceramic and porcelain capacitors can't withstand heat as well. Silver
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to manufacture them. Ceramic capacitors were also used in the 1920s due to a shortage of mica, but by the 1950s silver mica had become the capacitor of choice for small-value RF applications. This remained the case until the latter part of the 20th century when advances in ceramic capacitors led to
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They are sometimes informally referred to as mica capacitors. Any modern reference to mica capacitors can be assumed to mean these, unless pre-World War II equipment is being discussed. Even though these capacitors are extremely useful, silver mica capacitors are less commonly used today due to
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bulkiness and high cost. There is a high level of compositional variation in the raw material leading to higher costs in relation to inspection and sorting. They are getting closer to obsolescence as advances are made in ceramic and porcelain materials.
104:. These had even worse tolerance and stability than other clamped capacitors since the mica surface is not perfectly flat and smooth. References to mica capacitors from the 1920s often refer to this type.
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mica remains widely used in high-voltage applications, due to mica’s high breakdown voltage. Silver Mica capacitors are used at 100 V to 10 kV, ranging from a few
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than paper so capacitors can be made smaller. In 1920 Dubilier developed a capacitor consisting of a flaked sheet of mica coated on both sides with silver. He formed the
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Noor
Syuhada Zakuan, Woo Haw Jiunn, Tan Wimie, "Energy in a portable world", p. 100, ch. 4 in, Tan Winie, Abdul K. Arof, Sabu Thomas (eds),
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Now obsolete, these were in use in the early 20th century. They consisted of sheets of
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these are assembled from sheets of mica coated on both sides with deposited
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Mica has been used as a capacitor dielectric since the mid-19th century.
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Polymer
Electrolytes: Characterization Techniques and Energy Applications
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Greater stability, since there are no capacitive airgaps that can change
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the replacement of mica with ceramic in most applications.
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invented a small mica capacitor in 1909 which was used in
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139:Airtight enclosure removes the risk of
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