We found this circuit in a 1977 National Semiconductor Databook. The circuit can use other FETs like the BF245 and has an input impedance of 10 megohms. The circuit gain is unitary.
This circuit was obtained in a 1964 Electronic Design. The circuit uses components from that time,...
This pocket-sized VHF receiver was found in Radio Electronics magazine from January 1961. It uses...
Found in a Maxim documentation, this 1980s circuit drives 4 LEDs on a bar scale. The circuit does...