Résumé :
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"Retro Design Reimagined After reading about a restoration project on an old Tektronix L-C meter, Charles realized that the device is a brilliant design given the limitations of the era. That inspired him to embark on a similar design but using modern techniques and technologies. Topics Discussed How to build a retro L-C meter design using modern technologyThe circuit designThe oscillator designWhy the components were chosenHow the L - C measurement math worksHow to develop the firmwareHow to do the calibration Tech Used Microchip Technology ATtiny4313 MCU74HC161 counterJ310 or 2N5484 JFET6×2 LCD module with LED backlightingAnalog Devices AD8606Texas Instruments (TI) LMV722 Vishay capacitors How do we measure capacitance or inductance? Numerous instruments are available to do this—the simplest of which is the “C” measurement on many digital multimeters. That and other similar tools generally fail in accurate measurement below 1,000pF. While doing some RF work, I needed to measure chip capacitors down to about 10pF, and none of the inexpensive multimeters available on eBay and elsewhere could do the job accurately. The Australian magazine, Silicon Chip, recently published a two-part article on restoring a Tektronix T130 LC meter designed in the 1950s [1]." (Extrait de Circuit cellar n°376)
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