This simple combination lock accommodates codes from 1-9 digits long, with the only restriction being that the same digit cannot be used twice. The circuit shows strapping for a 4-digit code, in this ...

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This simple code lock circuit described here is of an electronic combination lock for daily use. It responds only to the roght sequence of four digits that are keyed in remotely. If a wrong key is ...

Commercial curve tracers have existed for decades. But designers without access to one can create a simple circuit that uses a function generator and oscilloscope to generate JFET transfer and ...