Simple Variable Resistor or Potentiometer With a Pencil!

 

Simple way of making a variable resistor with the graphite (carbon) inside a pencil. I my childhood, pencils used be called lead pencils, though I have never seen lead inside pencils, it was all graphite. Maybe it was there earlier and that was the reason for the old name. Colour pencils seem to be made of something else. I had checked continuity of some colour pencils and found it beyond the range! Not sure whether they could be used for high value potentiometers. I have not checked.


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