Found in a 1967 Electronics World, this preamplifier uses an integrated circuit from that time, difficult to obtain today. The maximum frequency is 15 kHz.
In fact, this circuit found in a Radio Electronics from November 1964 is a high voltage generator whose...
This configuration was found in old documentation and is valid for most general purpose NPN...
This is the project found in a 1981 publication, but it is still viable. It is a simple AM...