Orban OPTIMOD-FM 8600Si, Руководство по эксплуатации

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OPTIMOD-FM DIGITAL INSTALLATION
2-23
up to eight characters long. It is used to identify your 8600Si to Orban’s PC Re-
mote application, and appears on the Main Screen when the 8600Si is being con-
trolled by the PC Remote application.
A) Navigate to Setup
>
Next
> T
IME
D
ATE
A
ND
ID > S
TATION
ID
.
B) Use the knob to set the each character in the ID. Use the
Next
and
Prev
but-
tons to control the cursor position.
C) When finished entering your name, press the
SAVE
button. If you escape to
the main screen from Setup, you can now see the station name toggle on the
main screen.
The following steps are not included in Quick Setup, but you may need to perform
them as part of your initial setup of the 8600Si.
1. Activate the 8600Si’s ITU-R BS412-9 multiplex power controller (op-
tional).
[Skip this step if ITU-R BS412 is not enforced in your country. At the time of this
writing, it is only enforced in certain European countries.
If your country does
not enforce ITU-R BS412, set the ITU412-9 control to OFF.]
[If you are planning to use the 8600Si in its stand-alone stereo encoder mode,
make sure that the multiplex power controller is turned off until you have fin-
ished setting up the other stereo encoder parameters. Otherwise, it will interfere
with setting output levels.]
A) Navigate to Setup
> S
TEREO
E
NCODER
>
Next
> ITU412.
B) Set the multiplex power threshold by holding the
ITU412
button down and
turning the knob so that the display indicates 0.0 dB
.
If your transmission system introduces overshoot in the signal path after
the 8600Si (including the transmitter), instead set the multiplex power
threshold so that it equals the amount of peak overshoot (in dB) in the
transmission system. If you do not do this, the 8600Si’s ITU-R BS412 con-
troller will set the average multiplex power too low.
The easiest way to measure system overshoot is to turn the multiplex
power controller off temporarily. Then set the 8600Si’s output level (us-
ing its built-in 100Hz reference tone) so that the transmitter produces
±
75 kHz deviation. Finally, play program material with lots of high fre-
quency energy and bass transients (like bright rock music with heavy kick
drum) and observe the peak deviation produced by the program mate-
rial. The overshoot is the amount (in dB) by which the deviation with
program material exceeds
±
75 kHz deviation.
See the notes on the
M
PX
P
OWER
O
FFSET
control on page 3-44 and ITU-R
Multiplex Power Controller on page 3-80.
2. Set up modulation reduction to compensate for subcarriers, if needed.
In the United States, F.C.C. Rules permit you to add 0.5% modulation for every
1% increase in subcarrier injection. For example,
if your subcarrier injection to-