Applying an operational of the time, this circuit of an old documentation can be elaborated with modern operational. The feed must be symmetrical.
This old amplifier, with germanium transistors, was found in a Japanese technical magazine in...
This is the well-known lightning lamp that was published in the March 1988 issue of Saber...
This VFO was found in a 1980s documentation. The central frequency is given by the crystal and the...