This source was originally suggested by Delco in a 1969 documentation to power amplifiers up to 50 W. The transistors are of the time admitting modern equivalents.
We found this oscillator in a publication for radio amateurs from the 70s. The circuit generates...
We found this circuit in a 1982 publication, but all the components used are still common in our...
We found this circuit in a 1976 technical documentation, but it can be assembled with modern...