Found in a Philips documentation from the 90s, this circuit uses transistors from that time. Modern general-purpose transistors can be used.
This circuit allows the activation of a remote telephone bell made with a common piezoelectric capsule. The...
This is the traditional audio preamp configuration with the National Semiconductor LM382. The...
This class B push-pull amplifier circuit with a few hundred milliwatts of power was found in an...