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 three-transistor circuit was found in Radio Electronics magazine from May 1969. The circuit is...
This beat frequency oscillator was found in a 1980s documentation. The original FET has a grounded...
With this circuit it is possible to make the selection of transistors and their test according to the...