| 摘要 |
1,235,522. Counters. LEHMKUHL A/S. 1 Nov., 1968 [9 Nov., 1967], No. 51947/68. Heading G4D. [Also in Division H4] Morse signals are ciphered by an inverter, enabled by the signals, which is fed with evenlyspaced pulses which have positive or negative polarity according to a random pattern. An oscillator in a transceiver, Fig. 1 (not shown), generates sine wave 2a, Fig. 2, from which are derived signals 2b and 2c. Signal 2b passes to an inverter which inverts 2b whenever a signal 2d is high. Signal 2d is provided by a random generator, e.g. a counter arrangement, controlled by 2c. The resulting random pulse signal 2e is used to cipher the morse signal 2f. |
