A capacitance meter built from discrete ICs

2009-05-15 23:58 by Ian

Not much to say about this one. It was a project that I saw in an issue of Popular Electronics before it became Poptronics. It is a capacitance meter built from discrete ICs. It creates an RC oscillator and counts the number of wave-fronts over a given period of time to arrive at a value for the unknown capacitance.

Unit face:

Top of the PCB: