System information

Chapter 15 ‒ Interference Detection and Avoidance
The AXT400 receiver can detect narrowband and wideband interference from both analog and digital devices.
Examples of devices that cause interference:
• Analog and Digital wireless
microphones
• "White Spaces" devices
• Intercom Systems
• In-ear Monitoring Systems
• Wideband FM modulation
• Digital TV signals (DTV)
• Analog TV signals
Dual Digital Signal Processors (DSP) in the receiver analyze the RF signal for signs of interference that can degrade
the audio signal. When interference is present, the receiver screen turns red and displays one of the following warning
messages:
Interference Alert
Displayed on the home screen when low-level interference is detected.
Interference at this level may not be audible or may only cause a slight disruption
to the audio signal. All receiver controls can still be accessed, and If the
interference is not audible, a frequency change may not be necessary.
If Interference Avoidance is set to Auto mode, a frequency change will not
occur unless the strength of the interference increases to trigger an Interference
Detected message.
Interference Detected
Displayed when high-level interference likely to disrupt the audio signal is detected.
The menu screen displays on-screen options for changing to a clear frequency or
if Interference Avoidance mode is set to Auto, the channel will automatically switch
to a clear frequency deployed by the Spectrum Manager.
If the Interference clears without being addressed or if a frequency change is
made by the Spectrum Manager, the LCD screen will return to its normal color.
The detection message indicating time elapsed since the interference occurred will
remain on the screen for up to 60 minutes or until dismissed.
Vocal 1
634.225 MHz
Interference Alert
Radio
Audio
Util
Tx
From: G: 8 Ch: 40
TV: 41 OUT: Mute
FDhh
Vocal 1
INTERFERENCE
677.025 MHz
Manual
Ignore
Switch
!
In crowded RF environments, interference can come from anywhere. Other wireless microphones, intercoms, and a
growing number of digital devices all have the potential to interfere with wireless audio channels. Interference from these
devices can strike without notice, compromising the audio signal and creating dropouts.
To counter the threat of interference, Axient receivers are equipped with sensitive interference detection circuitry that give
advance warning when interference is present. Adding a ShowLink™ Access Point and Spectrum Manager enable the
following options for avoiding interference by switching to a clear frequency:
• Receiver, ShowLink Access Point, and Spectrum Manager: The Spectrum Manager automatically deploys a clear
frequency to the transmitter and receiver. Interference Avoidance can be automatic, or manual for situations requiring
precise timing.
• Receiver and ShowLink Access Point: Manual synchronized frequency changes between the transmitter and
receiver.
• Receiver: manually switch both the transmitter and the receiver to a clear frequency
Types of Interference
Interference Detection
90
Part 3: System Operation