The maximum frequency of this circuit is 500 kHz. We found it in a documentation for radio amateurs from the 1980s. The integrated circuit used is uncommon today.
In this circuit, from a 1977 publication, we have the traditional version of a filter that rejects 1...
The integrated circuit used in this application is uncommon today. However, the basic...
This physical line servo control uses components that are not currently common. The circuit is from...