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.
Found in a 90s Popular Electronics, this circuit is interspersed between the filter and the...
This circuit is from an 80's documentation. The integrated circuit is from the time and the...
This circuit was found in a 80s American documentation. The zener diodes determine the points of...