Nautel NV15, Operation And Maintenance Manual

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NV15/NV20 Operations and Maintenance Manual Operating the transmitter
Issue 3.2 2013-10-01 Page 2-57
– 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.