Hello there. rather than writing my question out, I have made a video instead with my circuit in simulation. So that it provides more details to you. Please do bare in mind that the SPDT switch which I am showing you in the video only makes a connection once like the RESET (Push to make switch) shown in the video. The D2 component is the Thyristor (SCR) which has 3 pin outs, anode, cathode and gate. Please watch this video before you read further on this thread as this video contains my explained question. So:- The junction on the R is pressed making the connection only once which triggers the RED lights and they stay on whereas the buzzer only stays on for 3 seconds. And when the function is on the G making the connection only once, only the green lights stay on but the buzzer only stays on for 3 seconds. SW1 RESET switch will turn off the lights once they are on (whether if they are green or red) Thank You!