| 摘要 |
PURPOSE:To make it possible to measure the delay time of a transmission system, by combining a signal generator of which the level is stepwise changed, a pulse generator synchronous to a delay signal after passing the transmission system and a generator with a longer pulse width so as to successively delay the delay time. CONSTITUTION:The step signal P21 from a signal generator 21 is received and a pulse signal P22 delayed t30 in rising is inputted to a pulse generating circuit 22 to generate a pulse P23 synchronous to the rising of the pulse P22. A pulse generating circuit 23 syncyronizes with the rising of the signal P21 to generate a signal P24 having a pulse width wider than tw1 and this signal P24 is imparted to circuits slightly different in delay times to each other to generate pulse signals P31, P32... with dilay times t31, t32... while the pulse signal P23 is imputted to one terminal. The outputs of FF 251, 252... are inputted to light emitters 261, 262.... By emitting lights from the light emitter 261, 262... when the outputs of FF 251, 252... comes to H, it is discriminated which FF comes to H and a delay time can be measured. As the result, the delay time of each transmission system becomes easy to be aligned. |
