This circuit is used in magnetic tape recorders, having been found in documentation in the 1960s. The circuit uses Japanese transistors, and the critical components are transformers.
The base of this circuit is one of the four Norton amplifiers existing in an LM3900 integrated circuit....
This simple CMOS metronome circuit can be mounted in a small box, providing both sound and light...
This circuit of an old American publication uses RF transistors to obtain unit voltage gain, but...