This circuit for the car was found in the April 1990 Radio Electronics magazine. The speaker is 4-ohms.
This circuit was found in a Philips documentation from 1966. Its purpose is to drive the solenoid...
This 9 V amplifier has a gain of 20 and provides a power of a few hundred milliwatts. The circuit is...
Found in a 1964 Electronic Design, this circuit shows how to modulate a signal with a dynamic low...