HOT-STANDBY

For redundant configurations ELBER has developed an advanced RF Hot Standby switch that operates with both analogue and digital signals.
The logic of operation is very simple: a power detector continuously monitors the RF power of the two same frequency transmitter outputs. If the RF power of one of the two signals falls below threshold, the other signal is presented to the RF switcher output. The threshold value is selectable through the user interface, with 1 dB hysteresis.
The RF Hot Standby has two different functional modes: forced mode and automatic mode.
In the former case one of the two inputs signals, chosen by the user, is directly routed to the output.
In automatic mode, the RF power of both transmitters is supervised. In addition two relay inputs, one for each inputs, is available. If Input A's power is above threshold and no alarm is received through the relay contact, then transmitter A is directed to the output. If one of these two conditions is not satisfied, the same control is performed on Input B and signal B will be directed to the output; if both conditions are true, otherwise Input A will be directed to the output as it has a higher priority. The 1dB hysteresis ensures that there is no continuous switching between the two transmitters.
The RF Hot Standby switch is available in both indoor (RFSW-02) and split type versions for outdoor configurations (RFSW-02/P + RFRL/W).
In the first case the equipment, housed in a 1U rack, receives directly the RF input signals, coming from the transmitters, through two coaxial cables.
In outdoor configuration the switcher is split in two components: an indoor control unit (RFSW-02/P) and an outdoor weatherproof RF housing (RFRL/W) that receives the RF input signals, coming from the external RF transmitting heads, through two waveguides/coaxial cables. The RF switcher control unit receives from the two transmitting indoor control units, through separate connections, the voltages representing the current RF output Power Level of the respective external RF Heads. The switcher control unit monitors these voltages and based on the level of these values, through an RG216 cable, signals the external weatherproof RF housing to switch out the correct external transmitting head. Please refer to back page for a block diagram of each respective systems.