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Bistable flip-flop circuit

This is another "how-to" with logic gates and NO PUZZLE.
Whenever you want to make something that changes periodically it's state you can use this method.
Besides the tractor beam and the laser-catcher combo you need two logic gates, an inverter and a hold gate.
here is how to connect:
laser catcher (at the tractor beam) -> inverter -> hold -> tractor (switch polarity) and the object you want to periodically change it's state.
Connect the weighted cube switch on the ground with the reset (angled plate) of the hold gate.
Note: Set the Tractor beam to start activated and start reversed.