MACKIE HDR24/96 - Manual (Page 75)

HDR 24/96
Time Code Chase Time Code Chase
Engaging the Time Code Chase mode causes the HDR24/96 transport to follow time code (MTC or
SMPTE) coming from an external master source. If disengaged, the HDR will go off line and will no
longer follow the incoming time code. Time Code Chase will only work if the correct cabling is in
place to a generating time code source machine. Engaging the Time Code Chase mode causes the HDR24/96 transport to follow time code (MTC or
SMPTE) coming from an external master source. If disengaged, the HDR will go off line and will no
longer follow the incoming time code. Time Code Chase will only work if the correct cabling is in
place to a generating time code source machine.
Engage the Time Code Chase mode in one of the following ways: Engage the Time Code Chase mode in one of the following ways:
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• Click the CHASE TC button the GUI Tools Panel located in the
column just to the left of the Current Time display.
• Press the T. CODE CHASE button on the transport front panel. It’s
located at the far right of the row of buttons above the floppy disk
drive.
• Press the T. CODE CHASE button on the Remote 48. Look to the left
of the Transport.
There is no access to this function on the
Remote 24.
When Time Code Chase is engaged,
pressing the PLAY button causes the PLAY
button to blink, but the transport won’t start
playing until time code is received. It is not actually necessary to first put the slave HDR24/96 into
Play as it will take off by itself as soon as time code starts flowing. This is also true for the Stop, fast
wind, and locate functions, which all follow the time code master. The STOP, fast wind, and LOC
buttons also have no effect. Instead all transport control comes from the master (which is why they
have the names slave and master),
Lock-once-only when using unreliable time code
You can disengage TC Chase on the fly, however, without interrupting the HDR's transport
motion. This is handy if you're working with a poor quality or intermittent time code source,
for example a stretched analog audiotape or an analog channel from an inexpensive VCR. By
disengaging TC Chase after the HDR24/96 has locked to the external TC position, the HDR
can freewheel from then on, unaffected by the unstable time code. Synchronization may not
be perfect, but this is a means of working with problem time code.
NOTE: When operating in sync with external time code, you’d normally stop the HDR24/96
playback by stopping the time code master, not the recorder. If you’re recording when chasing time
code, pressing Stop or Play will punch out of recording.
ANOTHER NOTE: The HDR24/96 does not resolve its sample clock to incoming time code.
Although the HDR is constantly checking the status of the external TC when chasing, it only
establishes the transport time at the initial lock-up. Once the HDR transport has jumped to the time
code time and started running, it counts the passage of time on its sample clock (whatever source has
been designated), while continuously monitoring the incoming time code. It will stay "locked" as
long as the time code doesn’t drop out or otherwise become corrupt for longer than ten frames.
During those ten frames the HDR will "freewheel," waiting for the TC problem to correct itself. If
the TC returns the HDR will continue to chase. If not, it will drop out of time code chase mode and
will stop.
Technical Reference 75