Using 3 ports, this rectangular oscillator was found in the March 1996 issue of Electronics Now magazine. The maximum frequency is a few megahertz, determined by R1 and C1.
We can use the trigger point of 555 to detect voltage levels or thresholds, in a circuit as shown...
This circuit was found in a technical documentation from the 90's. The transistors can be...
This circuit generates signals that can be adjusted in a small range around the frequency of the...