| 摘要 |
<p>798,218. Electric distributers; photo-electric distributers. MARCONI'S WIRELESS TELEGRAPH CO., Ltd. July 5, 1956 [Nov. 23, 1955], No. 33572/55. Class 40 (3). [Also in Group XL (c)] In one embodiment of a radio directionfinder (see Group XL (c)), the outputs of aerials 1, 2, 3 are connected in turn to receiver-detector RD by cyclically controlling the conductances of crystals Kl, K2, K3 in synchronism with the presentation of slots SL1, SL2, SL3 in drum CD, driven by motor M, between lamp EL and photo-cells PE1, PE2, PE3, such that when a photo-cell is energized the corresponding crystal provides a low-impedance path and the other two crystals, being high-impedance, ensure that the corresponding aerials act as reflectors to the other.</p> |
