发出: issue; send out; give out; d ...呼救信号: distress signal; emergency p ...呼救信号: distress signal; emergency pulses; signal for help; sos◇呼救信号频率 distress frequency呼救信号器: rescue beacon船舶呼救信号: sos呼救信号波道: emergency radio channel呼救信号频率: distress frequency紧急呼救信号: emergency message烟雾呼救信号: smoke distress signal一个呼救信号: an sos遇难呼救信号: distress signal; sos signal遇险呼救信号: distress signals; rescue message（船舶遇难）呼救信号，救命: sos save our ship，a me age for help; sos save our ship，a message for help船舶遇难呼救信号: sos save our ship a message for help呼救信号发生器: distress message generator呼救信号脉冲宽度: emergency width降落伞呼救信号: parachute distress signal无线电报呼救信号: radiotelegraph distress signal无线电呼救信号: radio distress signal无线电话呼救信号: radiotelephone distress signal遇险呼救信号广播: mayday broadcast国际通用的紧急呼救信号: sos save our souls无线电话中呼救信号。: mayday遇险无线电话呼救信号: mayday国际通用的呼救信号, 船遇难时的呼救: save our souls
