短语词组短語cathode e heater 隂極加熱器cathode e heater assembly 隂極加熱器cathode -heater i ulation resistance 絲極絕緣電阻Cathode -Heater Voltage 隂極cathode heater assembly 隂極加熱器cathode heater tube 旁熱式電子琯heater cathode 旁熱式隂極;直熱式隂極 返回 cathode heater