6
AUTO CH1 AUDIO OK
PRI 1 CH 3 NO AUDIO
Figure 5 - ATB-300 Auto Mode Display
When the ATB-300 detects an audio level below the silence threshold for the pre
selected time interval it will look at the priority memories and switch the lowest priority
channel which is active to the output. The display will indicate a loss of audio on the top
line of the LCD and will indicate the input which was switched to the output on the lower
line along with its activity status. It will also close the fault detected relays contacts
available on the rear panel remote connector. Pushing the red X key will reset the
warning as well as the relays. If the rear panel remote is enabled, an input is provided to
do this using an external closure as well.
AUDIO LOSS DETECTED
AUTO CH 5 AUDI O OK
Figure 6 - ATB-300 Silence Detected Display
Note that the ATB-300 is capable of detecting a subsequent loss of audio on the
channel that was automatically selected. If such an event should occur, the priority list
will again be used to select the first available active channel in the list.
Audio Restored Look Back Feature
The ATB-300 has the ability to monitor the designated primary channel after a loss of
audio has been detected by the silence sensor if the unit is in the automatic mode. If
audio is restored to the primary channel after a user programmed number of minutes
the unit will revert back to the primary channel automatically.
The factory default setting for the look back feature is disabled. To enable the look back
feature follow the procedure below:
1. Place the unit in the manual mode by pressing F1
2. Toggle F3 until the display says AUTO RETURN FUNCTION – factory default is
DISABLED.
3. Press the UP arrow to set the number of minutes the unit should wait before
reverting back to the primary channel only after audio has been restored to the
primary channel. The unit can wait from 1 to 60 minutes before reverting back to
the primary channel.
