It’s got two wheels and it’s coming for your job.
Kick it like grandpa!
We will explore the science behind analog sound synthesis, learning how capacitors, resistors and op amps interact to create audio waves.
At the end of this project, you will have a simple analog synthesizer.
Material List
Safety First
Part 1: The Core Circuit
Insert the TL072 op amp over the gap on rows 15 to 18.
Be careful that the half circle indent is on row 15.
Use a jumper wire to connect 18a to the top positive power rail.
Use a jumper wire to connect row 15 to the positive bottom power rail.
Connect 23d to 16d using a jumper wire.
Connect 23c to 15c using the 2m Ohm resistor.
Connect 17b to 10b using a jumper wire.
Connect 19a to 15a with a 0.022 µF capacitor.
Connect 23b to 19b with a 0.022 µF capacitor.
Part 2: Going to Ground
Connect 19e to 19f using a jumper wire.
Connect 21i to the blue Ground rail using a 280 Ohm resistor.
Connect 21h to 19h using the potentiometer.
Be careful! Do not put any potentiometer pins on rows 18, 17, or 16!
Part 3: Trigger
Connect 10a to 5a using the 180K Ohm resistor.
Connect row 10 to the bottom Ground rail using the 10K resistor.
What % of 180K is 10K? 5%! We’re voltage dividing the Micro:bit’s signal to make it 5% smaller.
Part 4: Micro:bit
Connect an alligator wire to GND (blue, ground)
Connect an alligator wire to Pin 1 (yellow)
Connect the signal wire (yellow from Pin 1) to row 5
Connect the ground wire (blue from GND) to the Ground rail.
Part 5: Power
Connect V- to the top power rail.
Connect V+ to the bottom power rail.
Connect V0 (blue) to the bottom Ground rail.
Part 6: Sound
Connect an alligator wire to the sleeve (blue, ground)
Connect an alligator wire to the tip (white)
Connect the sleeve (blue) to the bottom Ground rail.
Connect the tip (white) to 15d.
