Despite being from a 1969 publication, the transistors used have current equivalents such as BC548 and BC558. The circuit generates signals from 1 500 to 20 000 Hz and 4 scales.
We found this circuit in a 1988 documentation, but all the components used are still common today....
This variable high frequency oscillator circuit was found in an old English documentation. The...
This crystal fundamental frequency oscillator can operate at frequencies up to a few tens of...