Comtech EF Data XPA-200 Installation And Operation Manual page 32

XPA200-7984-I-OPT1, X-Band SSPA
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.
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.
option for another project that is not available to Comtech.
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
A to Antenna
A + B to
Antenna
B to Antenna
A + B to
Load
* A & B must have equal carrier magnitude and frequency.
XPA200-7984-I-OPT1, Rev.2
The Mitec factory explained that this was an
VPC Applied
Pos. Power
1 A and B
A only
B only
A & B not
2
phase
adjusted
A & B phase
adjusted*
3 A and B
A only
B only
A & B not
4
phase
adjusted
A & B phase
adjusted*
Table 2.2 Variable Phase Combiner Operation
Power Observed
at Load
(less I.L.)
Full Power of B
Half Power of A
Half Power of B
Partial Power of
A & B
Negligible Power
Full Power of A
Half Power of A
Half Power of B
Partial Power of
A & B
Full Combined
Power of A & B
Installation
More
However,
Power Observed
at Antenna
(less I.L.)
Full Power of A
Half Power of A
Half Power of B
Partial Power
of A & B
Full Combined
Power of A & B
Full Power of B
Half Power of A
Half Power of B
Partial Power
of A & B
Negligible Power
2-4