| 摘要 |
<p>A portable signalling unit includes a gas discharge tube and a continuously cycling drive circuit which produces successive discharges through the tube, a control instumentality being provided whereby the continuously cycling of the circuit may be overriden and brought under the control of a programming device which cause the discharges through the tube to follow a continuously repeating pattern. The pattern may represent the Morse code for SOS or any other desired signal.</p> |
