This is a very common circuit in the days of xenon flashes for cameras. This is from a Radio Electronics magazine from November 1965. It uses an SCR and has manual triggering.
This Salen-Key filter can use any operational amplifier and other frequencies can be obtained by...
This circuit can be adapted to be used in a follow the line robot. It was found in the May 1962...
The circuit in the figure uses two of the 4001's four gates to trigger a relay in a timed manner. The...