图中
The complete telephone man e He was mobile, mechanized and well equipped. With his tools around his waist he carried telephones on his back chest and in his bicycle sack. As today telephone men 80 years ago were safety -minded which in that era included wearing your sleeve guards and trouser clips
The complete telephone man He was mobile, mechanized and well equipped. With his tools around his waist, he carried telephones on his back, chest and in his bicycle sack. As today, telephone men 80 years ago were safety-minded, which in that era included wearing your sleeve guards and trouser clips
ne telepnone is an electrical instrument Speaking to the transmitter makes its diaphragm(震动膜) vibrate. this varies the electric current, causing the receiver's diaphragm to vibrate. This duplicates the original sound
The telephone is an electrical instrument Speaking to the transmitter makes its diaphragm（震动膜） vibrate. This varies the electric current, causing the receiver’s diaphragm to vibrate. This duplicates the original sound
TELEPHONE LINE RECEIVER TRANSMITTER CARBON GRAINS CARBON, E GRAINS r雄越 TD TRANSMITTER RD RECEIVER BATTERY