这部简易电话机制作简单,可以在几十米至一二百米距离内通话。材料:炭精话筒二个(电话上的受话器能把强弱不同的电流变成声音,也叫听筒),耳机二只(阻抗600Ω以上的耳塞机也可以),一号干电池四节,导线(可用塑胶绝缘双股胶合线)若干。 This simple phone is easy to make and can talk within tens of meters to 1200 meters. Material: two carbon microphone (the phone’s receiver can the strength of different currents into sound, also called the earpiece), two headphones (impedance of more than 600Ω earbuds can be), the first four batteries, wires ( Available plastic double-ply insulated plastic) number.