Paradise 205486 REV F User Manual

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 205486 REV F 

Operations Manual, HPA2, Compact Outdoor SSPA 

The Signal Box also contains two phase shifters. These phase shifters are in cascade with 
the RF input to HPA 1 and HPA 3. These allow the system to achieve optimum power 
combining and are factory set for optimum combining across the full bandwidth of the 
amplifier. They should not normally require adjustment in the field unless and amplifier has 
been replaced.  
 

 
Under normal system operation, HPA 1 and HPA 3 are on-line. Their output power is 
combined at the magic-tee waveguide combiner. The waveguide combiner has an integral RF 
sampler that provides a sample of the RF output sample at -40 dBc. This port feeds an RF 
attenuator / diode detector combination. The detector’s output voltage is sent back to the 
Signal box via a coaxial cable and fed to the FPRC-1200 Redundant Controller. 
 
The 1:2 Fixed Phase Combined System is controlled by an FPRC-1200 1:2 external      
Redundancy Controller. Detailed information on the installation and operation of the FPRC-
1200 can be found in the unit’s operations manual, Paradise Datacom drawing #201138.  
 
The FPRC-1200 can be used in automatic or manual mode. In manual mode if a fault occurs 
in one of the amplifiers, a fault will be indicated on the front panel but no waveguide switch 
change will occur. In automatic mode  the controller will determine the appropriate waveguide 
switch positions and switch the remaining two amplifiers on line.  This will ensure that the  
system is operating at full output power capability.   
 
The FPRC-1200 front panel is shown in Figure 8-9. In most cases the user will place the 
controller in Auto mode so that the controller can determine the proper switch position in the 
event of an amplifier failure. The mimic display shows the position of each waveguide switch 
by lighting an LED in the waveguide switch path.  

In normal operation, HPA 2 should be selected as the standby amplifier. HPA 2 is the  middle 
amplifier on the amplifier frame. This allows HPA 1 and HPA 3 to be combined by the 
waveguide combiner. If HPA 1 or HPA 3 were to ever fail, HPA 2 can be switched in place of 
either HPA 1 or HPA 3 and the system will still maintain full output power capability over the 
full operating bandwidth of the amplifier. Figure 8-10 shows the FPRC-1200 with HPA 2 
selected as the standby amplifier.