The circuit shown is from old English documentation and can be made with BC548 transistors for low power ones. The 2N3055 must be mounted on a heat radiator.
This circuit is a handset receiver that picks up the signal emitted by a coil under the rug or...
This circuit emits a sound whose frequency depends on the resistance of the circuit under test....
This circuit was found in a 90’s Electronic Engineering. The signal is sinusoidal with the...