This circuit was published in an article in Electronics Now magazine in October 1995. The circuit includes a power supply. The power transistors are equivalent.
With the configuration shown in the figure, a single pulse for a counter can be obtained from a...
With calibrated RV1 it is possible to find a zener diode voltage. The integrated circuit is 0 741...
This circuit was found on an 80's Ham Radio. The transistor admits equivalent. The circuit can...