This circuit was found in a Popular Electronics from the 90s. The transistors are general purpose, and the gain depends on the ratio between R2 and R1.
With this circuit it is possible to visualize the characteristic curve of a component on an...
This game of speed or who is the fastest uses a digital display. The circuit was found in a 1991...
This amplifier was found in a 1967 Japanese documentation. The circuit has no output transformer, but the...