1. Wiki
2. freewheel

From http://tweakheadz.com/sync-mmc-mtc-smpte/ :

Freewheel or "flywheel" Sync.
In the days of tape sync there were often dropouts in the timecode. Freewheel sync will interpret the value. You may be able to set an interval of time that allows this to happen.

Click to expand...

The drawback of setting the freewheel value too high is that once timecode stops being transmitted, the receiving device will continue on its merrily way, until it realizes it too should stop.