The circuit is from 80s Siliconix documentation. The integrated circuit is from the company and is not common today. It can be used operational equivalent more common in our times.
This circuit is from Radio Electronics magazine from June 1958. The tuned range at the time was...
Found in Popular Electronics from the 90's, this tuned to infrared modulated receiver uses a PLL....
This circuit was found in the March 1979 issue of Radio Electronics magazine. Integrated circuits must...