The system he has come up with is so simple it’s borderline genius. The PWM signal in question is fed through a piezo speaker in parallel with a resistor. The output from the speaker is then ...

[Jana Marie] must agree with this sentiment, one of her latest projects involves building a tool to generate a PWM signal and test servos using an Attiny25/45/85. What tools have you build recently?

The resistor and capacitor form a single pole low-pass filter. So, the circuit concept takes the output of an onboard PWM, filters it to create a DC signal that is set by the PWM’s duty cycle. The DC ...

Back in 2011, Elektor presented a DIY Ultrasonic Directive Speaker using an array of piezo ultrasonic transducers (up to 200) ...