为了在实验中更明显地演示电磁波的发射和接收,笔者曾用NE555集成电路组成振荡发射部分。如图1,经过多次实验,发射频率稳定性好,发射距离在10米以上。可满足课堂教学演示和劳技课的实验教学。接收部分采用图2的装置,制成一个简易场强计,通过电流表的指针偏转情况反映接收电磁波的强弱,比较直观,即使在阴雨天,发射接收均可实施,能明显 In order to more clearly demonstrate the emission and reception of electromagnetic waves in the experiment, I have used the NE555 integrated circuit to form the oscillation emission part. As shown in Figure 1, after several experiments, the transmission frequency is stable and the launch distance is more than 10 meters. It can meet classroom teaching demonstrations and experimental teaching of labor skills classes. The receiving part adopts the device of Fig. 2 to make a simple field strength meter, which reflects the strength of the receiving electromagnetic wave through the pointer deflection of the ammeter, which is more intuitive. Even in the rainy days, the transmitting and receiving can be implemented and can be obvious.