emitter ballast resistance

例句：

1. 1.The light bulb is an emitter of light.
   灯泡是一个发光体。
2. 2. The radio is an emitter of sound waves.
   收音机是一个声波发射体。
3. 3. The solar panel is an emitter of electricity.
   太阳能电池板是一个电力发射体。