
PCB-4000 1+1 Phase Combiner Revision 2
Introduction MN/PCB4000.IOM
1–3
TheblockdiagramsshowninFigure1‐2depictthemajorcomponentsofthe1:1phasecombined
system.(ThesediagramsemployComtechEFDataHPODs–HighPowere dOutdoorAmplifiers–as
thedesignatedSSPAs.)
The PCB‐4000 1+1 Phase Combiner Control Box (PCCB) contains a microprocessor‐based M&C
circuitboardtocontrolthesystem.Interconnectionisasfollows:
• ThePCCB commu
nicates with each SSPA via control cables that are attached from the
PCCB“SSPACOM1|J2”and“SSPACOM2|J3”connectorstoeachSSPA.
• It is also through this con nection that the PCCB receives it prime power to operate. A
+24V signal fr
om each SSPA is diode OR’ed to provide redundant operating power for
thePCCB.
• A“Y”cableconnectstothe“SSPASWOUT|J5”connectorforcontrolofthewaveguide
switches.MonitorandControl(M&C)communicationwiththePCCBisaccompli shedvia
the“SYSTEMCOM|J1”connector.
Note:Inordertoavoidam
biguities,allcommunicationtoeachSSPAisalsoaccomplishedviathe
PCCBM&C.
The PCCB provides a weatherized housing for the necessary input RF components. System
interconnectionisasfollows:
• Aninput RFredundancyswitch,controlled viath
e“RF INPUTSWITCH |J6” connector,
selectswhichRFpathisdirectedtotheoutput.
• The output RF signal is fed into an in‐phase divider, which equally splits the signal in
phase and amplitude to the “SSPA 1 OUT | J9” and “SSPA 2 OUT | J10”
outputconn
ectors.
o The RF path to the “ SSPA 1 OUT | J9” output connector contains a manually
adjustablephaseshifter;thisphaseshifter isusedtoequalize thephasedifference
ofeachSSPAsignalpathtoachievemaximumsystemoutputpower.Itisaccessible
via a small co
ver panel. This critical component is factory set and should only be
adjusted,ifneeds arise,bycarefullyfollowinganappropriatealignmentprocedure–
seeChapter3.INSTALLATION,STARTUP,
ANDTROUBLESHOOTINGPROCEDURESfor
furtherinformation.
o TheRFpathtothe“SSPA2OUT|J10”outputconnectorcontainsalengthofcoaxial
cablethatisfactorymanufacturedtoprovideequalphaselengthpathsfromtheRF
inputtoeachPCCBoutputwhentheadjustablephaseshifterissettoitsmidp
oint.
Thisprovidesamaximumadjustablephaserange.
There are also several isolators inside the PCCB that maintain good system Voltage
StandingWaveRatio(VSWR).YoushouldnotalteranyRFcableinside(oroutside)ofthe
boxthatispartoftheRFsignalpath.
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