The selectivity is reasonably good, even at the high end of the band. A wavetrap can be used to null nearby stations.
即使在频率高端，此线圈仍能保持良好的选择性。添加陷波器可以减小强台的干扰。
2
A wavetrap is very useful for crystal set reception, but is also great for reducing strong signals on a regenerative receiver.
一个陷波器是非常有用的水晶接待组，而且是伟大的接收信号强的再生减少。
3
The measurement and examination of wavetrap coil and coupling filter used for power line carrier communication system are an important part to ensure the electric power system operating normally.