Orban OPTIMOD-FM 5518, Руководство по эксплуатации

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2-26
INSTALLATION ORBAN MODEL 5518
put level for the equivalent of 90% modulation, not counting the subcar-
riers. (90% + 20% = 110%.) The pilot injection will thus be about 8%
modulation instead of the desired 9%. Adjust the
Setup > S
TEREO
E
NCODER
> Next > P
ILOT
L
VL
control as necessary to produce 9% modu-
lation (

6.75 kHz deviation). This will ordinarily require you to set the
P
ILOT
L
VL
parameter to “10%.”
7. Set digital output and configuration level.
[Skip this step if you will not be using the digital output.]
[See the notes in step 6 immediately above.]
A) Navigate to
Setup > I/O C
ALIB
> D
IG
O
UT
C
ALIB
.
B) Set the
DO P
RE
-E
control to
P
RE
-E
(for preemphasis),
P
RE
+J17
,
J.17
or
F
LAT
.
C) Set the
DO R
ATE to 32, 44.1, 48, 88.2, or 96 kHz.
The 5518’s fundamental sample rate is always 32 kHz, ensuring that the
output bandwidth is always strictly limited to 16 kHz and that the proc-
essed signal can be passed through a 32 kHz uncompressed STL without
addition of overshoot. However, the internal sample rate converter sets
the rate at the 5518’s digital output. This adjustment allows you to set
the output sample rate to ensure compatibility with equipment requiring
a fixed sample rate.
D) Set the
P
ILOT
S
YNC
.
The
P
ILOT
S
YNC control determines the reference frequency source to
which the 19 kHz pilot tone frequency is locked. (To do this, the DSP
clock is locked to this frequency.) The choices are
D
IG
I
N (the AES3 or
AES11 signal appearing at the 5518’s digital input),
R
EF
I
N
(the 10 MHz or
1x wordclock applied to the 5518’s
R
EF
I
N BNC connector), or
I
NTERNAL
(the internal crystal-controlled DSP clock oscillator).

If D
IG
I
N
is chosen and no valid signal is available at the unit’s digital
input, the 5518 automatically switches the sync source to the
R
EF
I
N
BNC connector. If there is no valid digital input signal at the reference
input, the sync source defaults to the 5518’s internal clock.

If
R
EF
I
N is chosen and there is no valid input signal at the
R
EF
I
N BNC
connector, the sync source defaults to the 5518’s internal clock.
E) Press
Next
. Then set the
DO S
YNC .
You can choose
P
ILOT
S
YNC (the DSP clock frequency reference as deter-
mined by the
P
ILOT
S
YNC
control) or
D
IG
I
N
(the output sample rate is syn-
chronized to the sample rate appearing at the 5518’s AES3 input).

If D
IG
I
N
is chosen and no valid signal is available at the unit’s digital
input, the 5518 automatically switches the sync source to the source
determined by the
P
ILOT
S
YNC control.
F) Set the desired output
W
ORD
L
ENGTH .
[14], [16], [18], [20], or [24], in bits
The largest valid word length in the 5518 is 24 bits