7400 competition entry: Capacitance meter

Alvaro built a Capacitance meter out of logic chips for the Open 7400 Logic Competition. His project measures capacitance of a capacitor and displays it on a 7-segment display.

It works by using the said capacitor in a RC oscillator, which changes its output frequency proportionally to the capacitance in it’s RC circuit. The frequency is then measured by comparison to a known stable clock. The video above shows it in action.

Via the contact form.

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  1. hi :) can you give me the list of components you used in making the capacitance meter? this design would be my project on my subject, so please tell me the components and values. thanks!

    1. Sure, care to send me an email ? Note that some of those components (mainly caps) had to be adjusted slightly due to inaccuracies in voltages and transistors.

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