Nautel NX25, Руководство по эксплуатации и обслуживанию

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NX300 Operations and Maintenance Manual Operating the transmitter
Issue 3.0 2012-11-01 Page 2-53
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AES Input Level -
Defines the AES input level (in dBFS) that will result in 100% modulation depth. Set
between -30 dBFS and 0 dBFS, according to the input signal level.
•
Balanced Analog Input Level -
Defines the Bal Analog input level (in dBm) that will result in 100%
modulation depth. Set between -20 dBm and +12 dBm, according to the input signal level.
Digital Settings
( Figure 2.38 on page 2-54 )
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Data Source -
Select the source for the OFDM (digital) signal (AES1 or AES2).
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DRM Bandwidth -
Select the bandwidth of the DRM signal to be transmitted. This setting only sets the
parameters of the mask shown on the spectrum analyzer. Transmitted signal bandwidth is set at the I/Q
source (DRM modulator). Select 4.5 kHz, 5 kHz, 9 kHz, 10 kHz, 18 kHz or 20 kHz.
•
Frequency Offset -
In AM+DRM mode, sets the frequency offset between the AM signal and the DRM
carriers. Set between -20 kHz and +20 kHz.
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Power Differential -
In AM+DRM mode, sets the difference between the AM carrier power and the RMS
power of the DRM carriers. The level is approximately based on the input signal to the exciter and may
require adjustment to obtain the exact level. Set between 0 dB and 40 dB.
•
Digital AES input Level -
Defines the full-scale AES input level (in dBFS) for the I/Q stream. Set between
-30 dBFS and 0 dBFS
•
IBOC BW -
In IBOC mode, sets the bandwidth for the IBOC signal. Select 5 kHz or 8 kHz.
Audio Loss
( Figure 2.39 on page 2-54 )
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Mod Loss Timeout
-
Determine if an action should be taken on the loss of a modulating signal. Select
Yes or No. Default is No. If Yes, the following sub-fields appear:
– Action: select the action to take on the loss of a modulating signal. Select None (no resulting
action), Inhibit (inhibits the RF output, fans and B+ voltage until the audio returns) or Change
Preset (changes the active preset).
– Mod Loss Preset: displayed only if Action is set to Change Preset. Select the preset from the drop-
down list that will activate upon the loss of a modulating signal.
– Timeout Minutes: sets the delay, in minutes, between audio loss detection and the resulting action.
Enter a value between 0 and 255 minutes.
– Timeout Seconds - sets the delay, in seconds, between audio loss detection and the resulting
action. Enter a value between 0 and 59.9 seconds
– Threshold - sets the threshold for audio loss detection. Enter a value between 0 and 100%