9 – Operations related to timecode–Chasing to timecode
66
TASCAM DA-98HR
1
Go to menu group 4, move the cursor to
Park Posi
(park position) and press
ENTER
:
2
Play and stop the master tape.
3
Turn the DA-98HR’s
CHASE
on, if it is off.
4
Use the
§
or
¶
keys to turn the
TEST
parameter to
on
.
The DA-98HR rewinds so that the relative dif-
ference is zero. When the DA-98HR has
stopped, go on to the next step below.
5
Play the timecode master.
When the value shown on the screen has
stopped changing and is stabilized, go on to the
next step below.
6
Turn
TEST
to
off
(
§
or
¶
key). The opti-
mum park pre-roll time for the timecode mas-
ter is now stored.
9.6.9
Absolute and relative difference
The offset as set above (9.6.2, “Setting timecode off-
set”) can be called the “absolute difference” between
the two times. However, if the slave machine “wan-
ders” (actually, this is unlikely), the offset (theoreti-
cal difference) will not be equal to the 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 absolute and relative differences between
master and slave machines:
1
Go to group menu E:
2
Move the cursor to either
Abs Diff
(absolute difference) or
Rel Diff
(rela-
tive difference). The appropriate value is
shown on the bottom line of the display screen.
9.6.10 Rechasing timecode
When timecode is received, the DA-98HR can either
constantly monitor the internal off-tape timecode (or
the synthesized equivalent as set in 9.2, “Tape time-
code mode”) and the external timecode, issuing
“speed-up” and “slow-down” messages to the trans-
port to keep itself in sync (rechasing), or it can syn-
chronize once and run freely, ignoring the incoming
timecode.
While the DA-98HR 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-98HR 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
timecode, though, you may want the DA-98HR to
rechase the master.
P a r k
P o s i t i o n
T E S T
o f f
0 2 s 0 8 f
2 5 F
Master
10:15:12:12
Slave
10:05:12:08
E x t
T C
˘ A b s
D i f f
T a p e
T C
R e l
D i f f
G e n
T C
A B S
T i m e
0 0 : 0 0 : 0 0 : 0 4
2 5 F
Master
Slave (offset set to
+00:10:00:00
)
Tape counter shows:
10:05:12:08
but should be
10:05:12:12
Tape counter shows:
10:15:12:12
Absolute difference =
0010 00 04
Relative difference =
00 00 00 04