Features of a new Doppler VOR beacon

The paper describes the particular features of a recently developed Doppler VOR beacon which permits compatibility with conventional VOR receivers, without impairment of instrumental accuracy. Various reasons are given for the limited success of early DVOR beacons, and measures are described to eliminate their weaknesses. It is shown that the new beacon does not necessarily need any modification for the effective provision of multilobe technique. Hence, when used with a modified form of airborne receiver or a conventional VOR receiver plus attachment unit, a new order of instrumental accuracy can be achieved. Two types of receiver attachment are described, one involving a small modification of the beacon, but making adaptation to receivers already in use more practicable.