Recommended · for beginners
JK flip-flop
Why people recommend it
Ben Eater builds a JK flip-flop and uses an RC edge detector to shorten the clock pulse; cited in questions about that capacitor and master-slave designs.
Watch for: the RC edge detector around 3:19
In their words
Link to a video that shows the capacitor.
Omar and Lorraine on electronics.stackexchange.com, Nov 2019. CC BY-SA.
But in this video he uses the second one
Allen on electronics.stackexchange.com, Jul 2019. CC BY-SA.