This circuit was obtained in an American documentation from the 80's. The transistors can be equivalent to those indicated and the crystal can reach a few tens of megahertz.
Found in a 90s Elektor, this circuit makes use of general-purpose transistors, except T4 that can...
This circuit, from the 1990 Motorola Dataar Databook, can use any LM139 series comparator. The circuit...
The circuit in figure 1 is a dynamic test for FETs. The characteristic of a FET is displayed in...