This capacitive switch or approximation relay was found in a 1980s US publication. Power should not be from a transformerless power supply and could be 741. The FET could be any general purpose such as the BF245.
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This capacitive switch or approximation relay was found in a 1980s US publication. Power should not be from a transformerless power supply and could be 741. The FET could be any general purpose such as the BF245.