This third-order filter was found in a 1975 publication. The circuit must be powered by a symmetrical source. The components can be changed for operation on other frequencies.
This is the basic configuration of a function generator with the 8038 integrated circuit (uncommon...
This filter for receiving audio in telegraphy was found in a magazine 73 for radio amateurs, in an...
This circuit amplifies VHF signals in the two-meter range and is very critical, especially...