We started the session with a look at capacitors, which are components used to store electrical charge. We used ‘decoupling’ capacitors in project 05 in the starter kit to stabilize voltage across the servo motor and potentiometer. The slides are available using the link below.
We then worked together on project 06 “Light Theramin”. This project uses a photo transistor determine the pitch of a note played from a piezo buzzer. We used the tone function to sound the piezo buzzer by sending pulses of electricity from the Arduino’s digital pin to make the piezo vibrate at a given frequency. (The tone function operates similarly to the analogWrite function used in session 04, except this time we change the frequency of the pulses instead of the duty cycle. See page 71 of the project book for a visual description.)
In the project we also calibrated the phototransistor so that it responds to the full range of light values present in the room. We did this using the map function.
