This QST circuit generates 4 frequency signals according to the crystals used. Transistors admit equivalents although the indicated types can still be found with some ease.
Mouser Electronics is now offering a reference design board from ST Microelectronics STEVAL-WESU1...
Found in Popular Elecronics, this configuration also appears in this section, but obtained from other...
The circuit shown in the figure can be used on a data transfer bus using an appropriate family...