This circuit is from a 1966 NASA documentation. The circuit uses a photodiode as a sensor. The other components are from that time.
Found in a 1965 Electronic Design, this circuit divides the frequency of a 50 MHz signal by 2. The...
This circuit was found in a 1967 General Electric documentation. The components are from that...
This direct conversion receiver circuit was found in Radio Electronics from the 90s. The...