This circuit covers 400 kHz to 40 MHz in three bands according to the selected coil. The double MOSFET allows equivalent, since the original is not easy to obtain.
This circuit was obtained in a 1960 transistor manual from Sylvania. The circuit uses small...
This 1980s documentation circuit uses a 741 in a different high-speed comparator configuration. The feed...
This is the typical circuit of a 60's tape recorder. The circuit uses only two transistors and has a...