| 摘要 |
PURPOSE:To measure both continuity test sounds and noises with a simple constitution by using a BPF, level measurement device, a band illumination filter and a noise measurement device and producing a test call a continuity test sound transmission device in a call generation mode. CONSTITUTION:A continuity test sound transmitter 2 and a continuity test sound receiver 3 are stored to a main switch device 1. The receiver 3 contains a level measurement device 5 connected to a BPF4 and a noise measurement device 7 connected to a band illumination filter 6. These transmitter 2 and the receiver 3 are connected to a talking circuit connected to the remote side station via the device 1. Then the transmitter 2 delivers a test sound in a call generation mode. This test sound is looped back by 0dB from the remote side station and received by the receiver 3, the level of the received tone is measured by the device 5 and at the same time the noises are measured by the device 7. Thus it is possible to measure the transmission of channels with a simple constitution. |
