DIY Emergency Resistor - an Electronic Circuit Component

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Intro: DIY Emergency Resistor - an Electronic Circuit Component

Your in a cabin in the woods, your circuit is due tomorrow and the parts store is closed. You need is a few resistors now!

STEP 1: Gather the Materials

To make resistors you need a volt-ohm meter, some paper clips, slips of paper and a graphite pencil. I prefer a No. 2 pencil as a No. 1 is harder to find in an emergency.

STEP 2: Scribble Resistance

Applying steady pressure scribble a smudge with no line breaks on a piece of paper. The graphite in a No. 2 pencil has electrical properties. More familiar circuit resistors are made from carefully calibrated graphite wrapped in non conductive shell with connecting  leads protruding. Read http://en.wikipedia.org/wiki/Resistor

STEP 3: Add the Paper Clips

Push two paper clips onto the paper so the metal of each clip is touching the graphite smudge.

STEP 4: Measure the Resistor

Attach the leads of the volt-ohm meter to the paper clips and measure the resistor value. Move the paper clips closer together to decrease the resistor value.

Beware (mild): Don't let your fingers touch the leads when you are measuring the resistance.  Your human contact to the leads with body resistance will distort the meter reading.

Beware (medium): Don't let the paper clips touch. If the paper clips touch there is an electrical 'short' as there is no resistance and your circuit might get damaged.

BEWARE (HIGH): This is LOW VOLTAGE SOLUTION - - do NOT use this in high voltage circuits.

The results of this DIY resistor vary enormously - - you did it yourself!

Enjoy.

12 Comments

Why you talk do not use high voltage circuit.please tell me
Homemade lightbulbs are made in a similar way. When you attach the high-voltage to the paperclips, the graphite will glow brightly for a brief moment, then the paper will get too hot and catch fire.
The paper would catdch fire.
"If only we had a resistor we could complete the defense robot and stop the zombies!"

"No problem, I just need a pencil, a piece of paper and two paper clips."
Very nice instructable.
Very nice instructable.
Add a third paperclip in the middle and make a potentiometer :)
McGuyver would be proud!
Damn! This works? Nice thought!