We found this circuit in Radio Electronics Special Projects from 1992. The circuit turns on the power when the microphone plug is inserted into the input jack.
This circuit provides an audible signal when testing a TTL circuit. The circuit is from an old...
The power of this small amplifier reaches 75 mW per channel depending on the voltage and the load...
This circuit uses the 741 Operational Amplifier to drive two LEDs. The LEDs indicate the signal of...