Inovonics AM SiteStreamer+ SOFIA 567, Инструкция по установке и эксплуатации

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Threshold On (dB):
is the set point that the program must drop
below to trigger an alarm. Moreover, the program level must
remain below this set point for the number of seconds selected
with the
Time On (Sec):
slider. Even a quick burst of noise, or a
transient click will start the timing period to begin afresh.
The alarm automatically resets when the program level re-
attains a specified
Threshold Off (dB):
value and remains above
that point for the number of seconds set by the
Time Off (Sec):
slider.
In the setup illustrated on the previous page, the program must
fall below –30dB for a full 10 seconds to trigger an alarm. Then
when the program returns, it must stay above –15dB for 3 full
seconds for the alarm to reset. The reason for such hysteresis
in these levels is to make sure that legitimate program material
is what resets the alarm, not simply random noise in the ab-
sence of carrier. The 3-second reset time should ensure that
music or speech will remain above the –15dB level for that pe-
riod, but even a short program audio pause will restart the pe-
riod count and keep the alarm from resetting.
Low Signal
This alarm is similar to one just discussed for audio loss.
When the
Mute:
function is turned
On
, program audio from all
outputs is ‘squelched’ (silenced) during the alarm interval.
Mute: On
keeps random no-carrier noise from making a nui-
sance of itself when the incoming signal is lost.
The
RSSI (dBuV):
grayed-out bargraph gives the level of the in-
coming RF carrier.
Threshold On (dBuV):
and
Threshold Off
(dBuV):
set points are programmed in much the same manner
as the audio-loss alarm example above. Be sure to take
day/night power differences into account when setting these
parameters.
Overmodulation
This alarm is useful in signaling a transmitter or audio proces-
sor malfunction that causes the carrier to grossly overmodu-
late. The
Level (%):
and
Limit (%):
settings are calibrated in per-
cent-modulation in this case, which corresponds to 0dB on the
level meters. Do be sure to take both asymmetrical and MDCL
operation into account when setting the
Limit (%):
value (see
Page 18).
Follow the same strategy in setting
Time On (Sec):
and
Time On
(Sec):
settings as with the other alarms. In the case of overmod
these probably both want to be of relatively short duration,
perhaps on the order of just a few seconds.
Alarm Logging
In addition to local displays and messaging alerts for signal
and program audio problems, the alarm data are logged and
stored indefinitely. You can click on
View Alarm Log
near the
bottom of the page for a display of all alarms in chronological
order.
The log holds data on the type of
Alarm
, which monitored
Sta-
tion
it pertains to (important when the StationRotation feature