The RF protection A-B switch (RFABM) is a coaxial relay switch designed for automatic or manual operation. The switch is used in sub-headends with dual forward path feeds or in a protected ring system. If one of the RF feeds fails, the switch will change to the other input and maintain RF output. An alternate application is for dual return paths from a remote node or from a remote sub-headend.
The standard module includes wide band RF detection. The sum of all carriers present will determine the RF switching levels. There is an option to include RF filters for pilot based operation, such as with our 4.5 MHz return path pilot system. Pilot filters can also be ordered for forward path applications.
The module includes high isolation impedance matched RF switching relays, which are micro-processor controlled. The switching action may be initiated automatically or manually. In automatic mode, channel A has preference, unless it is outside the user-defined threshold range and channel B is inside thereof.
The module has programmable maximum and minimum switching thresholds . Comprehensive status monitoring of each module is available via the OCM user interface and can be output to remote status monitoring systems. |
