Free Circuit Diagram

Metronome is very important tool if you studying music playing. There are mechanical metronome device in the past, but today, electronic metronome is much more popular since it can be very simple, compact/small, reliable, and also has the most interesting feature: cheap. Here is one example of the electronic metronome schematic: Parts: [...]

It would be cool and elegant to a have mechanical sound character for our electronic metronome. This electronic metronome circuit will produce such sound, making your life more fun. Here is schematic diagram of the circuit: The metronome circuit consists of two 555 oscillators. The first oscillator is used to make high frequency [...]

Sustain effect in electric guitar is similar with compressor effect. The purpose of this effect is to make the note last longer when the string is plucked. The mechanism is actually work by controlling an amplifier gain, where the gain is automatically increased when the note fade out, therefore the note will be sustained to [...]

Octave shifting or frequency doubling effect for electric guitar is done by rectifying the original signal, just like AC to DC conversion inside your AC-DC power supply adapter. The circuit for this audio effect is not new, I’ve seen it on many publications. Here I present the circuit’s schematic diagram, but I’ve redesigned the circuit [...]

Thermoelectric cooler (TEC) or Peltier cooler is becoming popular because of its robustness and maintenance free characteristic. Here is one example of a linear thermoelectric cooler (TEC) driver circuit. This driver  is capable of delivering ±2A into a TEC. This circuit operates on a single +5V supply and drives the TEC in the most preferred [...]

The signal can be converted by piezoelectric films in many ways such as thermal to electrical (temperature sensor), mechanical to electrical (microphone), and electrical to mechanical ( a loudspeaker). The circuit is signal conditioning amplifier for piezofilm sensor which use three op amps and has a high-input-impedance differential charge. Here is the circuit : [...]