| 摘要 |
PURPOSE:To simplify various types of checks by transmitting pulses to a transmission line within a transceiver from a tester and checking the state from the number of pulses of the reception signals and the presence or absence of a collision signal. CONSTITUTION:The prescribed pulses are supplied to an amplifier 13 of a transceiver 3 from a pulse generator 33 of a tester 30, and the transceiver 3 delivers the transmission signal to a coaxial cable 2. In this case, the same number of pulses as that of a transmission mode are supplied to a check circuit 34 of the transceiver 3 as long as tap connection parts 22 and 23 are normal. No collision signal is supplied to the circuit 34. Therefore a decision circuit 343 decides the normalness of the parts 22 and 23. No pulse nor collision signal are delivered from the transceiver 3 if the parts 22 and 23 are short-circuited. While the pulse and collision signal are supplied to the circuit 34 if the parts 22 and 23 are opened. Furthermore the pulses more than a prescribed number are delivered to the circuit 34 when the cable 2 has a faulty reflection. Then a counter 341 gives the pulse count value to the circuit 343. In such a way, various types of checks are possible. |
