| 摘要 |
PURPOSE:To transmit an order line signal in any combination of a radio high frequency part and a modulation/demodulation part between confronting stations by frequency- modulating the order line signal with a line supervisory signal between the modulation/ demodulation parts of the confronting stations in a radio section. CONSTITUTION:In the case of the modulation/demodulation parts from a station A to a station B, the order line signal of an order input 21A is inputted to a modulation part 23 through a connection line 38A and is FM-modulated in an FM modulator for supervisory signal. An FM modulation wave is demodulated in the demodulation part 24 of the station B through a radio line, is turned into a voice signal and is outputted to an order output 21D through an order demodulation part 25. In the case of the radio high frequency parts 1A and 1B from the station A to the station B, the order signal of an order input 31A is outputted to the order output 21B of the modulation/demodulation part 2A in the station A and it is inputted to the modulation/ demodulation part 23 through a connection line 37A. Then, it turned into the FM modulation wave, is radio-transmitted, is demodulated in the demodulation part 24 in the station B and is turned into a voice signal. Then, it is inputted to the order modulation part 22 through a connection line 39B and is outputted to an order output 31D as an order call in the station B. |
