Eas Test - Orban Optimod-FM 8300 Operating Manual

OPTIMOD-FM DIGITAL
confusion or hesitation in the talent's performance unless the delay is above the
psychoacoustic "echo fusion" (Haas) threshold of approximately 20 ms and the tal-
ent starts to hear slap echo in addition to frequency response colorations.
The normal delay through the 8300 is about 15 ms. A 15 ms delay is comfortable for
most talent because they do not hear echoes of their own voices in their head-
phones. Further, the 8300 offers a second, ultra-low-latency multiband structure
with a delay of about 5 ms. Although this does not offer the same favorable trade-
off between loudness, presence, and low distortion as the optimum multiband struc-
ture, it is available for use in situations where a given individual cannot tolerate the
15 ms delay of the optimum structure. (However, management should carefully con-
sider whether compromising the sound of the radio station for its entire audience is
an acceptable price for indulging a given personality's demands.)
Because of the availability of both optimum and low latency structures, customers
can confidently replace an older, low-delay processor with the 8300 with no studio
wiring changes. Moreover, off-air cueing of remote talent is routine.
A better solution to the monitoring conundrum is this: The 8300's analog outputs
can be switched to provide a low-delay monitoring feed while still keeping the op-
timum multiband structure on-air (by using the digital or composite output to drive
the transmitter). The monitor feed has no peak limiting and thus cannot drive a
transmitter, but its 5 ms delay is likely to be more comfortable to talent than the 15
ms delay of the optimum processing chain because of less acoustic comb filtering.
If the talent relies principally on headphones to determine whether the station is on
the air, simple loss-of-carrier and loss-of-audio alarms should be added to the system
when the 8300's monitor output is used. The 8300 can be interfaced to such alarms
through any of its eight its GPI remote control inputs, cutting off the low-delay au-
dio to the talent's phones when an audio or carrier failure occurs.

EAS Test

For stations participating in the Emergency Alert System (EAS) in the United States,
broadcast of EAS tones and data can be accomplished in three different ways:
1. Run EAS tones and data through the 8300.
Note that 8300 processing may not allow the full modulation level as required by
EAS standards. It may therefore be necessary to temporarily defeat the 8300's
processing during the broadcast of EAS tones and data. Placing the 8300 in its
BYPASS Test Mode can defeat the processing. The BYPASS GAIN control allows
a fixed gain trim through the 8300. See "Test Modes," on page 3-55 for more in-
formation.
2. Place the 8300 in Bypass mode locally.
A) Navigate to S and set M
/ M
ETUP ODE
to B .
ODE YPASS
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INTRODUCTION