Employing the XR2206 IC, this circuit was found in the May 1977 issue of Radio Electronics magazine. The formula next to the diagram gives the component values as a function of frequency.
This stereo preamp uses only two germanium transistors. The circuit was found in old documentation using...
I found this circuit in a 1989 American publication called Electronics Handbook. The circuit...
This is the power source suggested in the old European publication for the CB19635E watch. The...