A method for transposing the time of an event as read at a remote station with one clock to the time frame of another clock at a master station when the clocks are not synchronized and are of insufficient accuracy to provide measurements to within a few microseconds relative to other time measurements which are likewise transposed to refer to the master clock. A list of TV line 10 synch pulse times are maintained at the master for a specific number of recent line 10 pulses. Along with the time reading for the event, the line 10 synch pulse time as read at the remote is sent to the master. The list of line 10 synch times maintained at the master is examined to find the time by the master clock for the same line 10 and the difference between the time by the remote clock and the time by the master clock is used as an indication of the time correction factor to be applied for the transposition. The time correction factor is compensated for the difference in propagation time for the TV signal transmission to the master as compared to the remote. The transposed time reading is compared to other transposed readings obtained from other remote stations to either determine the sequence of several events at the different remotes or to obtain a measure of quantities such as voltage phase angle or the position of a fault. Updating of the time correction factors is provided to compensate for drift of the clocks.
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