This circuit was obtained from the September 1977 issue of Radio Electronics magazine. The circuit is based entirely on transistors and two SCRs. The power supply with the inclusion of a battery is given.
This powerful source was obtained in an American documentation of the 80s. Some components are...
This simple transistor tester was found in a Japanese magazine in 1967. It tests general purpose...
This transistorized astable for LEDs was found in the January 1992 issue of Radio Electronics...