Nautel NV7.5, Operation And Maintenance Manual

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NV10/NV7.5 Operations and Maintenance Manual Operating the transmitter
Page 2-64 Issue 3.4 2016-08-03
– Auto Changeover Action:
users can select which preset they want the
transmitter to switch to in the event of an automatic exciter
changeover. This function is ideal for changing to a preset that has a
different HD PA Volts value, which is required when a different
exciter is active - e.g. HD Power Boost active exciter A requires less
HD PA Volts to comply with spectral mask, thus improving
dissipation. However if an automatic changeover to non-HD Power
Boost enabled exciter B occurs, the
Auto Changeover Action
preset
will have a higher HD PA Volts value (less efficient, but required in
order to comply with spectral limits).
– Mod Loss Timeout
: select
Enable
if so required. If
Enable
is selected
the following sub-fields will appear:
–
Action
: select the action to take on the loss of a modulating
signal post the timeout period. Select
None
(no resulting
action),
Inhibit
(inhibits the RF output and fans 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, post the timeout
period.
–
Timeout Minutes
: sets the delay, in minutes, between
modulation loss detection and the resulting action. Enter a value
in the allowable range of 0 and 255 minutes.
–
Timeout Seconds
: sets the delay, in seconds, between
modulation loss detection and the resulting action. Enter a value
in the allowable range of 0 and 59.9 seconds.
–
Threshold
: sets the threshold for modulation loss detection.
Enter a value in the allowable range of 0 and 100%.
– Hard Limiter:
select
Enabled
, then enter the hard limit threshold
percentage (allowable range is 0-160%, defaulted to 140%). If enabled,
the modulation level will be limited (audio signal clipped or
distorted) if it exceeds the hard limit threshold.