The TDT (Time and Date Table) contains only the current UTC time and date. It can be used for the internal clock of the receiver to synchronize.

TR 101 290
  • The TDT should be broadcasted at least every 30 seconds.
  • The time between receiving the last byte of the section and the first byte of the next section should be at least 25 ms.
  • The Scrambling Control must have the binary value '00' ( umscrambled )
  • Descriptors

    Descriptors may not occur in the TDT

    name bits description
    Table ID 8 Indicates to which table this section belongs, in this case TDT (0x70)
    section_syntax_indicator 1 Indicates whether a sub-table structure including CRC check is used.
    Reserved for future use 1 always binary value '1'
    Reserved 2 always binary value '11'
    UTC time 40 This 40 bit field gives the current time and date in UTC and MJD. The first 16 bits represent the 16 bits MJD, then the 24-bit UTC as 6 digits in 4-bit BCD.