Nick Grant


Week 2: Setting up a breadboard

Introduction to Physical Computing

For this week in physical computing, I experimented with using a breadboard.

My breadboard, Arduino, multimeter, resistors, and LED lights

In my multimeter, I inserted the Black probe into the “COM” jack, which represents ground. Then I inserted the Red probe into the “V” jack to measure for voltage. When I touched the two tips of the proves together, the meter beeped correctly.

Correctly working multimeter
My probes and alligator clamps

Initially I connected my breadboard to the Arduino, but I preferred using the DC power supply to free up space. I set the voltage to 5V. I connected the probes from my multimeter into the DC power supply, which I then connected to two wires in my breadboard via alligator clamps.

Testing the pushbutton

I connected the black wire to the negative column and the red wire to the positive rail, which created a current in my circuit. The positive wire is connected to my pushbutton and a 150-Ohm resistor. Each time I clicked the pushbutton, I opened the circuit. The resistor and LED light consumed energy.

LED lights in a parallel circuit

I added a second LED light to my breadboard, which created a parallel circuit. In a parallel circuit, the path for the current is divided. In both of my LED lights, the anode is connected to the resistor and the cathode is connected to the negative column of my breadboard. While this LED light is continuously lit, the current of the first LED is controlled by a pushbutton. I wonder if placing the pushbutton near the wires that connect to the DC power supply would create a scenario in which both LED lights are controlled by the pushbutton.

The sunglasses are my switch

In the final part of my lab, I created my own switch. I replaced the pushbutton with two wires that I connected to a pair of sunglasses that I found with my alligator clamps. I wrapped aluminum foil on the sunglasses, which is a conductive material. The current passed from my breadboard to my shades and into my breadboard again.

My biggest question is how I should approach drawing schematic diagrams for my future projects. Is there a common application that ITP students use?