An effective solution to the "racing" problem described in my previous video (https://youtu.be/st3mUEub99E) is the master-slave JK flip-flop which comprises two SR latches. In this video I explain how it works, build, and test it. Support me on Patreon: https://www.patreon.com/beneater You can get all the components used in this video from any online electronic components distributor (Jameco, Digikey, Mouser, etc). Complete parts list (everything in this video): - 1x 74LS02 (Quad 2-input NOR gate) - 1x 74LS11 (Triple 3-input AND gate) - 1x 74LS08 (Quad 2-input AND gate) - 1x 74LS04 (Hex inverter) - 4x LEDs - 2x Momentary "Microtivity 6mm tact switch" - 2x 1KΩ resistors - 22 gauge wire - 5 volt power source (e.g., a USB phone charger) - Clock circuit from https://youtu.be/kRlSFm519Bo