As a pre-processing step for transmitting a timecode, a checking information is retrieved from a linear time code (LTC). A checking data is created using the retrieved checking information. The checking data is superimposed on a vertical interval time code (VITC). As a post-processing step for transmitting a timecode, meanwhile, collating information corresponding to the checking information is retrieved from the LTC. A collating data is created using the retrieved collating information. Then, the checking data is retrieved from the received VITC. The retrieved checking and collating data are collated to verify, thereby, the presence or absence of errors in the received LTC.