Love tester

A love tester was a device developed by different species in order to detect the level of romantic passion of people. 

A Hydran love tester was found adrift in an asteroid field, prompting the crew of the RIS to try the device, only to find that the Simpsons were the only other race capable to use the Hydran contraption, who detected manethozine. Other species worked on love testers adapted to their own physiology, such as the Klingons and the Rakelli.