This circuit is from old documentation, but it can be implemented with modern transistors such as 2N2222 for bipolar and BF124 for FET. The crystal determines the operating frequency.
This configuration was found in a 1976 publication. The outputs of the logic circuits are applied to...
With this circuit it is possible to measure frequencies up to about 500 kHz using a common...
The very high-input impedance of the CMOS gate allows this kind of device to be used as a...