Orban OPTIMOD 6300 Operating Manual page 79

OPTIMOD 6300 DIGITAL
If you are driving a pre-emphasized channel and can bypass the channel's
internal preemphasis filter, use P
channel's preemphasis filter or if you will use the analog output for
monitoring, set the output F
NOTE: If the 6300 is set to emit either the AGC or M
choosing P
because there is no preemphasis-aware peak limiting anywhere in the
system and because the preemphasis filter before the output will cause
peak level to increase markedly.
C) You can use either program material or tone to set your output level (and
thus, your modulation). If you want to use tone, turn on the 400Hz calibration
tone. To do this:
a) Navigate to S
b) Set the M
c) Set T
ONE
d) Set T
ONE
e) Press the N
f) Set T
ONE
g) When you have finished with the tone, set the M
D) Using the AO 100% button, set the desired analog output level corresponding
to 100% modulation, using units of dBu (0 dBu = 0.776 V rms).
Refer to Setting Output/Modulation Levels on page 1-25.
If you have chosen AGC or M
will not be well controlled because no peak limiting has been applied to
this signal.
If you are using program material, make sure that the program material
is loud enough to produce peaks of frequent recurrence that cause the
6300's look-ahead limiters to produce gain reduction, thereby defining
the maximum peak level that the 6300 will produce.
If you use a TVAxxx preset (intended to process audio for analog preem-
phasized FM aural carriers), loudness will be correct compared to an
Orban processor for analog TV (like Optimod 8282 or 8382) if you set the
6300's AO 100% level so that the 6300's test tone generator, when set to
100 Hz and 100%, produces 100% modulation of the aural carrier. (For
systematic instructions, see step 13.M) on page 2-35.)
To make this work, you must set the D
(S
ETUP
will cause the processing to scale the look-ahead limiter drive and loud-
ness controller threshold appropriately so that on-air loudness is the
same as other stations using an Optimod-TV for analog television if these
stations are using a factory preset. Moreover, it will scale the loudness
meter so that it peaks at "0" on dialog when on-air loudness is correct.
This allows you to use the meter as a reference for customizing presets.
If overshoot in the transmission path following the 6300 causes peak
modulation with program material to be significantly higher than it is
LAT
-
RE E in the current step will cause very poor peak level control
> T .
ETUP EST
to T
.
ODE ONE
F to 400 H
REQ Z .
L
VL to 100%.
key.
EXT
C to L+R.
HAN
>D >R O ) and set the DO1 100% control to 0.0 dB. This
IALNORM EF UT
. However, if you cannot defeat the
RE
.
ODE
in step (A) above, the peak level
ULTIBAND
R
IALNORM EFERENCE
INSTALLATION
ULTIBAND signals,
to O
PERATE .
O to DO1
UTPUT
2-25