Orban OPTIMOD-FM 8600Si, Руководство по эксплуатации

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OPTIMOD-FM DIGITAL INSTALLATION
2-31
I) You can specify the amount by which the 8600Si automatically reduces main
and stereo subchannel modulation to accommodate subcarriers within the
modulation limits specified by the governing authority. See step 2 on page 2-
23.
10. Set analog output and configuration level.
A) Navigate to
Setup
> I/O C
ALIB
> A
NLG
O
UT
C
ALIB
> AO P
RE
-E
. Set the analog
output pre-emphasis to
P
RE
-
E (for pre-emphasis) or
F
LAT .
If you will use the analog output to drive a stereo encoder,
P
RE
-
E
pro-
vides the best performance because the stereo encoder does not have to
restore the pre-emphasis. (Its magnitude and phase response may not
perfectly complement that of the deemphasis applied by the 8600Si to its
processed output when the 8600Si’s output is set
F
LAT
. This can introduce
overshoots in the overall transmission chain.) However, if you cannot de-
feat the pre-emphasis in your stereo encoder or if you will use the analog
output for monitoring, set the output
F
LAT
.
If you are sending the analog output of the 8600Si through a digital link
that uses lossy compression (like MPEG, APT-X, or Dolby), set the output
F
LAT
.
Lossy codecs cannot handle pre-emphasized signals.
If you are going to use the analog output for headphone monitoring [see
step (B) below], set the output
F
LAT
.
B) Set the
AO S
OURCE
to
FM
,
FM+D
ELAY
,
or
M
ONITOR
.
FM: This produces a fully peak-controlled output suitable for driving a
transmitter.
FM+Delay: This produces a fully peak-controlled output suitable for driv-
ing a transmitter. Up to 16 seconds of diversity delay can be applied to
this output. To set the amount of delay, refer to step (9.F) on page 2-30.
Monitor: If you do not need the 8600Si’s analog output to drive a
transmitter, you may configure it to receive the output of the multiband
compressor before peak limiting. This signal is suited for driving head-
phones. The input/output delay is approximately 3-8 milliseconds (de-
pending on the setting of
AGC C
ROSSOVER
T
YPE
)
. Even though normal
8600Si presets have a delay of about 15 ms, which most DJs, announcers,
and presenters can learn to use without discomfort (although they may
need some time to become accustomed to it), the low-delay output will
cause less bone-conduction comb filtering. However, in most cases, the
low-delay output will not be necessary to ensure adequate talent com-
fort.
The normal delay is 15 ms except for “UL” (ultra-low latency) presets,
which have approximately 5 ms delay.
If have set the source to Monitor, be sure to set analog pre-emphasis to
Flat. See step (A).
C) You can use either program material or tone to set your output level (and
thus, your on-air modulation). If you want to use tone, turn on the 100 Hz cal-
ibration tone and set it to 91%.
The tone is calibrated with reference to the composite output and as-
sumes 9% pilot injection: 91% + 9% = 100%. The peak level at the ana-