This circuit was found in a Popular Electronics from the 90's. The transistors are general-purpose types and the loaded load depends on the voltage and must have a maximum current of 100 mA.
This circuit can be used in decoration or to draw attention, in a “fake” assembly for example. What he...
This sophisticated alarm with traditional components was found in an ancient American...
We found this AM radio in a 1957 transistor application manual, published by Raytheon. The...