| 摘要 |
<p>PURPOSE:To prevent detection signals in synchronized state from being transmitted when a tone signal is fixed at an H level. CONSTITUTION:A signal detecting circuit contains a phase synchronizing means 1 which generates a reproduced digital signal with use of an inputted digital signal and a synchronization detecting means 2 which detects the synchronous/ asynchronous state between the reproduced digital signal received from the means 1 and a digital signal and transmits the corresponding information. Furthermore an information transmission control means 3 is added to transmit the information received from the means 2 after turning it into the asynchronous information if the next changing point cannot be detected within a period set after the first chaning point of the digital signal is detected.</p> |
