Suggested by Mullard in an old documentation, this circuit is based on a common phototransistor and on transistors that may be the modern BC548.
This circuit can be used with receivers to attenuate signals that may cause interference. The...
This circuit was adapted from an Italian publication that no longer exists. This is “Onda Quadra”...
This ultra-low power metronome was found in a 1991 documentation. The output transistor is general...