This NEC commercial amplifier was manufactured in Japan in the 1960s. The circuit uses 4 transistors from the time and was powered by a 9 V battery voltage formed by large batteries.
We found this simple alarm circuit in a 1981 documentation. As we can see, it is a car alarm...
This small regulator was found in a Motorola 1968’s documentation. It is a current regulator using...
This low-pass filter with 741 op and symmetrical source was found in the August 1993 issue of...