Tascam DA-78HR - Manual (Page 60)

9 - Operations related to timecode
TASCAM DA-78HR
60
absolute difference. The “relative difference” is
expressed as below:
Relative difference = Absolute difference – Offset
Thus, if the offset is set on a slave machine to
+00:10:00.00 (10 minutes) and while chasing, the
two machines’ counters read as follows:
the slave is now 10 minutes and 4 frames behind the
master.
Since the slave is meant to be exactly 10 minutes
behind the master, the difference, +4 frames, is the
“relative difference” between the master and the
slave.
To view the and relative differences between master
and slave machines:
1 Press the SHIFT key so that the SHIFT indicator
is flashing, then press the MENU key until the
display shows TC-- ( TC-- ).
2 Press the SUB MENU key so that the display
shows DISP ( DISP ) followed by the current
setting.
3 Use the ▲ and ▼ keys to make the diff
( DIFF ) setting—the difference between the
received timecode and the actual position.
9.6.9 Rechasing timecode
When timecode is received, the DA-78HR can either
constantly monitor the internal off-tape timecode (or
the ABS equivalent as set in 9.2, “Tape timecode
mode”) and the external timecode, issuing “speed-
up” and “slow-down” messages to the transport to
keep itself in sync (rechasing), or it can synchronize
once and run freely, ignoring the incoming timecode.
1 Press the SHIFT key so that the SHIFT indicator
is flashing, then press the MENU key until the
display shows tc. chs-- ( TC CHS-- ).
2 Press the SUB MENU key so that the display
briefly shows RECHS. MD ( RECHS MD ) and
then changes to the current setting.
3 Use the ▲ and ▼ keys to choose between
RECHASE ( RECHASE ) and FREE ( FREE ).
While the DA-78HR is re-syncing (speeding up and
slowing down), playback output will be muted,
unless the clock is set to
INT . Usually you should find
that the DA-78HR does not need to rechase, however,
and you can leave it in free-running mode. If the
timecode master tape includes a break in the time-
code, though, you may want the DA-78HR to rechase
the master.
As well as selecting rechase, you can also select the
length of the “rechase window”. This means that if
the difference between internal and incoming time-
code is greater than the value of this window (1 or 2
seconds in the case of the DA-78HR), the synchro-
nizer will start to rechase.
1 Press the SHIFT key so that the SHIFT indicator
is flashing, then press the MENU key until the
display shows
tc. chs--
( TC CHS-- ).
2 Press the SUB MENU key so that the display
briefly shows RECHS. WD. ( RECHS WD ) and
then changes to the current setting.
3 Use the ▲ and ▼ keys to change between 1 and
2 seconds.
9.6.10 Bypassing timecode errors
As timecode is received from a remote master unit, it
may be subject to errors (dropouts on the timecode
master tape, etc.). These errors can cause synchroni-
zation failure (the DA-78HR will no longer be locked
to the timecode of the master unit).
You can set the DA-78HR to bypass and ignore
incoming timecode errors of up to 30 frames in
length, or up to 10 frames in length.
1 Press the SHIFT key so that the SHIFT indicator
is flashing, then press the MENU key until the
display shows
tc. chs--
( TC CHS-- ).
2 Press the SUB MENU key so that the display
briefly shows ERR. BYPAS. ( ERR BYPAS ) and
then changes to the current setting.
3 Use the ▲ and ▼ keys to change between 10
FRM ( 10 FRM ) and 30 FRM ( 30 FRM ).
9.6.11 Individual recording while chasing
timecode
If slave DTRS units are chasing a master DTRS unit,
the default action is for the slaves’ record status to
follow that of the master. If the slaves are connected
with TC as well as SYNC, and have TC rather than
ABS selected as the timing reference, this default
behavior can be overridden using the function
described here.
1 Press the SHIFT key so that the SHIFT indicator
is flashing, then press the MENU key until the
display shows tc. chs-- ( TC CHS-- ).
Master 10:15:12:12
Slave 10:05:12:08