Atec Agilent-E4916A - Manual (Page 4)

4
CL boards with fixed capacitors are
available as well as the CL board with
the trimmer. Around 20 different CL
boards with fixed C and a target
capacitance trimming function will
make your measurement with load
capacitance easier to handle and
much more reliable with substantially
less error components than other
solutions currently in use.
With the HP E4916A, you can mea-
sure a DUT with load capacitance
using the same test fixtures and load
capacitance as those for the network
analyzer. Thus no correction is
required to correlate your results to
those obtained with network ana-
lyzer.
Unlike other conventional network
analyzers, the HP E4916A searches for
the resonance point (zero-phase
point) in a unique manner for
improved efficiency.
It begins to measure the phase at the
lower end of the search range and
continues its search by changing the
frequency at specific intervals. The
resonance point lies somewhere
between the two adjacent points at
which the phase for one point is
negative and that for the other point
positive. This is the primary search.
Then, the HP E4916A slightly goes
back in the search range and changes
the frequency at smaller intervals
such that the phase becomes closer to
0. The HP E4916A repeats its mea-
surements until the phase is suffi-
ciently close to 0. This is the second-
ary search.
Benefit:
This method provides constant
frequency resolution regardless of the
measurement time, because there are
no needs to specify the number of
measurement points. In addition, the
power level is not interpolated.
Therefore, the specified power is
exactly applied to the DUT at the
resonance point.
Primary Search Range
Secondary Search Range
+
+
– – –
–
0°
θ
0°
θ
Resonance Point Determination by Recursive Search