Due to its high Q value (a measure of the properties that give the quartz crystal its unique ability to control a frequency) and its low cost, quartz (SiO2) is the material of choice for the production of piezoelectric devices. The internal constraints of communication devices also demand small frequency deviation as a function of temperature, and as consumer demand continually drives down the size and the cost of this equipment, the need for smaller piezoelectric devices that can maintain tight temperature performance and that are less costly to manufacture becomes increasingly greater. To avoid interference between transmitters operating in the same geographical area or on adjacent channels, it is essential that frequency be accurately controlled. As demand for space on the available radio-frequency spectrum grows, spacing between assigned frequencies has become tighter. Piezoelectric crystals typically resonate within narrowly defined frequency ranges and when suitably mounted they can be used in electric circuits as components of highly selective filters or as frequency-control devices for very stable oscillators. Conversely, when an alternating electric current is applied to opposite faces of a piezoelectric crystal, the crystal expands and contracts in concert with the alternating electric current. Today, this phenomenon is referred to as the piezoelectric effect. In 1980 the Curie brothers observed that when a permanently polarized material is subjected to a mechanical force an electric field is produced. The present invention relates to the field of quartz plate oscillators, and, more specifically, to a method for determining angles of cuts that produce quartz plates having low shifts in frequency as a function of temperature, and the manipulation of that method to reduce the effects of other electrical components. 23, 2002, which is a Continuation-in-Part of U.S.
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