Comtech EF Data XPA-200 - Manual (Page 32)

XPA200-7984-I-OPT1, X-Band SSPA Installation
XPA200-7984-I-OPT1, Rev.2 2-4
2.3 Notes on Combined/Redundant System Operation and Setup
The following paragraphs are intended to give a brief explanation
of system operation of the Comtech XPA200 SSPAs with the Mitec 2723
Variable Phase Combining and Redundant Switching System. More
detailed information can be found in each unit’s respective operating
manual. A review of the operation of a Variable Phase Combiner is
shown in Table 2.2 below.
(Note: The Load Overheat function mentioned in the Mitec 2723B manual
is not operational. The Mitec factory explained that this was an
option for another project that is not available to Comtech. However,
this should not cause any concern because the load is rated for 1000W
(convection cooling) and the maximum power possible into the load is
approximately 525W.)
VPC
Function
VPC
Pos. Applied
Power
Power Observed
at Load
(less I.L.)
Power Observed
at Antenna
(less I.L.)
A to Antenna 1 A and B Full Power of B Full Power of A
A + B to
Antenna
2
A only Half Power of A Half Power of A
B only Half Power of B Half Power of B
A & B not
phase
adjusted
Partial Power of
A & B
Partial Power
of A & B
A & B phase
adjusted*
Negligible Power
Full Combined
Power of A & B
B to Antenna 3 A and B Full Power of A Full Power of B
A + B to
Load
4
A only Half Power of A Half Power of A
B only Half Power of B Half Power of B
A & B not
phase
adjusted
Partial Power of
A & B
Partial Power
of A & B
A & B phase
adjusted*
Full Combined
Power of A & B
Negligible Power
* A & B must have equal carrier magnitude and frequency.
Table 2.2 Variable Phase Combiner Operation