Orban Optimod-FM 8300 Operating Manual page 76

2-28
INSTALLATION
If you are using program material, make sure that the program material
is loud enough to produce peaks of frequent recurrence that hit the
8300's peak limiting system, thereby defining the maximum peak level
that the 8300 will produce. In the U.S., we recommend using 900s peak
weighting on the peak modulation indicator, as permitted by F.C.C. rules.
This will cause the monitor to ignore very low energy overshoots and will
result in the highest peak modulation permitted by law.
In other countries, use a peak-indicating instrument as specified by the
regulatory authority in your country.
If you are required to implement the average modulation limits specified
by ITU-R 412-9, you may seldom see peaks hitting 75 kHz deviation. In
this case, we advise you to set the output level by using the 8300's refer-
ence 400Hz tone.
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 totals 20%, you can set the total modulation to 110% (82.5
kHz deviation). This implies that you must set the 8300's composite out-
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
E / N
NCODER
tion (6.75 kHz deviation). This will ordinarily require you to set the
P L
parameter to "10%."
ILOT VL
8. Set digital output and configuration level.
[Skip this step if you will not be using the digital output.]
[See the notes immediately above.]
A) Navigate to S
ETUP
B) Set the DO P -E control to P
RE
C) Set the DO R
ATE
The 8300'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 8300'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 DO S
YNC
You can choose I
8300's internal crystal-controlled clock) or E
rate is synchronized to the sample rate appearing at the 8300's AES3 in-
put).
E) Press N . Then set the desired output W
EXT
[14], [16], [18], [20], or [24], in bits
The largest valid word length in the 8300 is 24 bits
/ P L control as necessary to produce 9% modula-
EXT ILOT VL
/ IO C / D O C
ALIB IG UT
-E (for pre-emphasis), P
RE
to 32, 44.1, 48, 88.2, or 96 kHz.
.
(the output sample rate is synchronized to the
NTERNAL
S
ETUP
.
ALIB
+J17, J.17 or F
RE
(the output sample
XTERNAL
(word length).
L
ORD EN
ORBAN MODEL 8300
/ S
TEREO
.
LAT