[trebligdivad]

oh wow, this is like an RF Circulator - https://en.wikipedia.org/wiki/Circulator - which are wacky enough in themselves.

[Terr_]

> three- or four-port device that only allows a microwave or radio-frequency (RF) signal to exit through the port directly after the one it entered

Perhaps only superficially related (IANAElectricalEngineer) but that makes me think of multi-phase mercury arc-rectifiers.

https://en.wikipedia.org/wiki/Mercury-arc_valve