Circuit Project Electronic

How many times have you wished that there was a simple way to turn on that sub-woofer or some other piece of audio equipment, simply by sending it a signal? This ability is fairly common in commercial subs and some other gear, but there seems to be a complete absence of circuits on the net, [...]

The purpose of this circuit is to create a pair of sine waves for testing stereo equipment. While it is useful for many types of audio test tone generation, the circuit is specialized for the purpose of aligning an FM Stereo Modulator, like the type used in low power FM stereo transmitters. Two tone outputs [...]

Easy Circuit Pulse Generator by IC 1458
Output Pulse wave max 9V, supply voltage 9V,