Found in a 90’s Electronics Now, this circuit has its output connected to an audio amplifier. The transducer is the type that fits on the finger to monitor the transparency and thus the beats.
This simple 1 transistor circuit was found in an American documentation from the 60's. The...
Found in a magazine 73 for radio amateurs, this circuit makes use of general purpose transistors and...
The presented circuit allows to control the valve of a tap. The positioning of the emitter and the...