Optimod-AM 9400 V1.2 Operating Manual - Orban

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INTRODUCTION ORBAN MODEL 9400
two filters. (See step 8 on page 2-5 for installation instructions). The filter provides
complementary de-emphasis and a 10 kHz notch for off-air monitoring of NRSC
standard audio. The output of the rolloff filter accurately simulates the sound of a
standard NRSC receiver. Alternately, for use in non-NRSC countries, an adjustable
18dB/octave rolloff that complements the 9400's HF GAIN control can be selected
with jumpers (see Figure 2-4 on page 2-5). Figure 2-5 on page 2-6 shows the frequency
response of the Monitor Rolloff Filter for various settings of its ROLLOFF control.
If a different tonal balance is desired for off-the-air monitoring, install a simple program
equalizer after the Monitor Rolloff Filter and boost the 5 kHz region to taste.
Do not use a monitor rolloff filter to monitor the digital channel of a decoded HD
AM signal.
Headphones
In live operations, the throughput delay introduced by advanced DSP-based processing
like that used on the 9400 can cause a problem with the DJ or presenter's headphones.
See Low-Delay Monitoring for Headphones on page 3-10 for a discussion of
the 9400 low-delay monitoring feature.
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 9400 in its normal operating mode.
Note that 9400 processing may not allow the full modulation level as required by
EAS standards. It may therefore be necessary to temporarily defeat the 9400’s processing
during the broadcast of EAS tones and data. Placing the 9400 in its BYPASS
Test Mode can defeat the processing. The BYPASS GAIN control allows a fixed gain
trim through the 9400. See “Test Modes,” on page 3-54 for more information. Steps
2 and 3 below describe how to use BYPASS.
2. Place the 9400 in Bypass mode locally.
A) Navigate to SETUP > TEST > MODE and set MODE to BYPASS.
You can set the bypass gain with the BYPASS GAIN control located to the
right of the MODE control.
B) Begin EAS broadcast.
After the EAS broadcast, resume normal processing:
C) Set the MODE to OPERATE.
This will restore the processing preset in use prior to the Test Mode.