Orban OPTIMOD 8685, Руководство по эксплуатации, Страница: 70 / 357

2-16
INSTALLATION ORBAN MODEL 8685
modules, via a Dolby-E encoded bitstream (which is typically conveyed on audio
channels 1 and 2).
In the base unit, to emit an Rdd06-2008-compliant signal the 8685 must be re-
ceiving a valid input RS-485 serial stream that is compliant with Rdd06-2008—this
is necessary to synchronize the output metadata to video frame boundaries per
the Dolby specification. In units equipped with the HD-SDI module, frame sync
can also use the SMPTE 274M/296M video reference input or the signal appear-
ing at the HD-SDI input.
When a valid input stream is present, the 8685 passes this stream unchanged to
its output except for the following modifications:
•
The
ac3_dialnorm
word in the output metadata stream is reauthored so it is
the same as the 8685's active D
IALNORM
value.
•
The
ac3_dynrnge
word in the output stream is set to 0, indicating that the
downstream AC3 encoder must reauthor the line-mode DRC metadata, fol-
lowing the level compression profile found in the
ac3_dynrng1
word in the
input metadata.
•
The
ac3_compre
word in the output stream is set to 0, indicating that the
downstream AC3 encoder must reauthor the RF-mode DRC metadata, follow-
ing the level compression profile found in the
ac3_compr1
word in the input
metadata.
Future software upgrades will add more functionality to the 8685’s han-
dling of metadata, including the ability to specify a different level com-
pression profile than that found in the input metadata, and the ability to
handle 2.0 metadata in addition to surround metadata.
To maintain sync when using metadata, it is important to set the 8685’s audio
delay to one frame of the video associated with the metadata.
See step 14 on
page 2-19.
11. Choose a processing preset.
A) L
OCATE
to the Set Preset screen ( S
YSTEM
S
ETUP
> Q
UICK
S
ETUP
10 ).
B) Turn the knob until your desired preset is highlighted at the top of the screen.
C) Press the E
NTER
button to put your desired preset on-air.
This step selects the processing to complement various program formats.
There are presets for radio-style and television-style applications. The lat-
ter begin with “TV.”
The “TV xxxx” presets are tuned for strictly for digital television, while
the 2.0 parameters in the “TVA xxxx” presets are tuned to allow the 2.0
processing to be used for analog television transmissions that employ FM
aural carriers having 50
μ s or 75 μ s preemphasis. For instructions on how to
set up the 8685’s 2.0 processing for analog television, see step 11 on page
2-31.
After this step, you can always select a different processing preset, pro-
gram the 8685 to automatically change presets on a time/date schedule,