TRANSMISSION SYSTEM OF TEST INFORMATION

摘要

PURPOSE:To enable effective use of the channel of line, by assigning an arbitrary channel in the digital multiplex lines as the test channel and transmitting one or more bits in it as the test information bit. CONSTITUTION:The test information is fed to the test mix trunk 3 in the form of digitized signal. One bit in 8-bit of audio channel 8 of test personnel is replaced to the test information at the trunk 3. The test channel entered to the time sharing switch 5 from the trunk 3 is handled the same as conventional audio channel and fed to the station where the terminal test unit 9 is located. The data group to the conversion and multiplex unit 7 is switched via the test mix trunk 8 at the time sharing switch 6 of the terminal station. At the trunk 8, one bit of the test information only is picked up from the test channel and it is fed to the test unit 9. The test unit 9 performs the test for the tested telephone set 10 through the test line a or b and the test personnel of the test unit 1 can communicate with the telephone set 10.