HP 85027A/B/C Performance Tests
SECTION 4
PERFORMANCE TESTS
INTRODUCTION
The procedures
in this section test the directivity, test port match and dynamic accuracy
of the HP 85027 directional bridges using the
specifications of Table 1-1 as
the
performance standards.
Space to record the
specifications and test results am-c
incorporated in Tables 4-1, 4-2 and 4-3. Each test
procedure lists the equipment
required. You may substitute test equipment if the substitute equipment meets or
exceeds the critical specifications of Table 1-5. Each of the tests can be performed
without access to the interior of the
bridge.
PERFORMANCE TEST RECORD
Tabulate the results of the performance tests in Tables 4-1, 4-2 and 4-3. The
performance
test records provide space to list all of the tested specifications and their
acceptable limits. Test results recorded during incoming inspection can be used for
comparison with test results obtained after periodic maintenance, troubleshooting, repairs
or adjustments.
DIRECTIVITY
Description
Directivity is a measure of the ability of a directive device (in this case the HP 85027)
to discriminate between incident and ref lected signals. In principle directivity can be
measured when the test port is terminated with a perfect load to absorb (and thereby
eliminate) all reflected signals. In this perfect situation, any remaining signals detected
would be dim-ectivity errors, the i-esult of reflections due to imperfections of the bridge
itself.
Perfect loads do not exist. The following test procedures make allowances for the
erroi-s caused by the imperfect loads. Note that while there are no perfect loads, loads
do vary in quality and that quality directly influences the performance test results. Use
the highest quality load available.
4-1
