the term "gaydar" is a useful but is a simplification. there is actually a quite sophisticated homosensor suite in use. the sj radar is a 10-cm band set used for range and direction finding of surface gays. the sd radar is a 2-meter band omnidirectional set that provides early warning of aerial gays. the qc/jk sonar set incorporates both active "ping" capabilities as well as passive directional hydrophones, for detecting both surfaced or submerged lesbians.