Introduction to Electronics
Assignment 1: variable resistance and conductivity
555 timer in astable mode with speaker and different conductive materials
Current flows through the 555 timer circuit and the attached conductive material, which creates square wave oscillations that are output on a speaker.
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By changing conductive material(water, metal..), you change the resistance and the pitch of the tone.
schematic for 555 timer in astable mode with speaker and different conductive materials
