Dimensional Beacon

A device installed in a target dimension that emits a signal back to Earth so portals can lock on. Without an active beacon a dimensional traveller has no way to reach that world accurately. Only one beacon's signal registers per dimension — the stronger overrides the weaker — and the home equipment cannot tell from the signal whether a beacon is being switched on and off, only whether it is present at all. Lock-on takes time as upstream information distorts. STD:FWH:Ch 27