Abstract: A religious artifact including at least one scroll hand-written on kosher parchment in Hebrew, using flexible water-resistant kosher black ink. Such ink, when dry, does not dissolve in water and does not crack or peel off the surface, yet, when a mistake needs to be corrected, such ink can be scraped off the surface of the parchment without leaving a visible ink residue on the surface and without causing substantial damage to the parchment. The present invention provides for kosher scrolls which are less prone to and more resistant to becoming non-kosher, than scrolls of the prior art.

Abstract: A capacitive ratioing oscillator circuit utilizing a prior art pressure capsule, but through modification of the state variable oscillator circuit achieves a digital output which varies with the square root of the capacitance ratio C35 C.sub.p /C.sub.r. In this sensor the dielectric constant of the pressure media is measured in time with the pressure difference measurement. The oscillator includes a differentiator-inventor step herein each of capacitors C.sub.r and C.sub.

Abstract: A pressure sensor includes a variable capacitor responsive to an applied fluid pressure to predictably change capacitance value. A tuned oscillator circuit having an inductive impedance includes the variable capicitor and simulates a resonant inductive-capacitive circuit not including an inductor. The tuned circuit oscillator to provide a signal with a period which is a function of the variable capacitance value, and of the applied fluid pressure. Additional elements are provided for precise measurement of the variable signal, correction for temperature effects, correction of measurement aberrations, and production of an output signal in a preferred format.

Abstract: A dual capacitive pressure sensor includes matched variable capacitors which are immune to vibration and acceleration, but which respond equally to changes in external fluid pressure level. The structure of the sensor is configured to avoid calibration drift as the sensor ages, as well as to provide electrical shielding for the variable capacitors of the sensor.

Abstract: A conditioning circuit for use with a pressure transducer is disclosed which provides a digitally readable electronic output signal indicative of capacitance sensed by the pressure transducer. The circuitry of the present invention utilizes an R-C charge/discharge circuit, thereby enabling the circuitry to be substantially more compact than previously utilized L-C circuits. The circuitry is usable with either pressure transducers having a single capacitance or those including a reference capacitance, and the circuitry provides a high resolution, high precision output.

Abstract: A quartz pressure transducer is disclosed which includes four or five elements, three of which are diaphragms containing deposited metal electrodes on both sides thereof. Since the electrodes are all on the diaphragms, the transducer disclosed herein is highly resistant to errors caused by changes in temperature, while retaining excellent resistance to errors caused by acceleration or vibration forces. The transducer may be constructed as either an absolute pressure sensor or as a differential pressure sensor, and in the primary embodiment contains a reference capacitance which may be used by appropriate electronic circuitry to provide compensation for acceleration or vibration forces, making the output of the pressure transducer of the present invention a highly accurate, highly sensitive indication of pressure sensed.