This is to demonstrate as to how the "GRAPHITE" inside a pencil could be used as a "TRANSDUCER" , to convert sound vibrations to electrical signal. This assembly of the double ended pencil suspended on two shaving razor blades picks-up the sound vibrations in close proximity. Affected by vibrations, the 'Graphite" in the pencil acts as a Variable Resistor in the electrical circuit of the Microphone in-put of the sound card of Computer. By adjusting the microphone input level to the sound card , good quality audio could be recorded.I have used "Audacity" audio recording software on my Ubuntu 16.04 Personal Computer.
2. In this project I have attached two razor blades on cardboard box using electrical insulation tape. Blades can also be fitted on a wooden block using screws.
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