When the switch controlling S and R signals are open there is no change on the Q and /Q signals. When the switch controlling Set (the S node) is switched closed, Q2 will switch OFF (if not already OFF) and turn Q1 ON (or maintain Q1 ON if current already flowing through the base) and /Q node will be pulled low.
svg schematics by matt-chv is licensed under CC BY-SA 4.0
